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Spotlight on obstetrics
ing the medication orally and 441 patients receiving the medication vaginaUy. They intervened in 67 patients in the oral study and 42 patients in the vaginal study before successful cervical ripening. The most common reason for intervention was an abnormal fetal heart rate with or without excessive uterine activity (39 in the oral group and 23 in the vaginal group). There was no significant difference in cesarean delivery rates between the two groups or in the hours between administration and delivery. No adverse neonatal outcomes were noted. These investigators concluded that the efficacy of misoprostol given orally was similar to that given vaginally, but that the oral route was associated with a higher frequency of excessive uterine contractility and the necessity for intervention. Level I.
ACOGCLINICALREVIEW TO EXPAND Because of numerous requests from our subscribers, ACOG Clinical Review has increased its publication frequency to 10 issues per year in 2002. This way we hope to be better able to cover the large number of publications in our specialty. We thank the members whose response to this publication has been overwhelmingly positive. We are also appreciative of our publisher, Elsevier Science, Inc., who is making this expansion possible. With the new expansion, ACOG has selected a new editor, Dr. Morton Stenchever, to serve as the Editor of the series and the former editor, Dr. Ralph Hale, will now serve as Associate Editor.
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Oral and Vaginal Misoprostol Carlan SJ, BouldinS, BlustD, O~BrienWF. Safetyand efficacyof misoprostolorallyand vaginally: A randomized trial. Obstct Gyneco12001;98:107-12. Synopsis: This study included 1004 women with a singleton fetus who had medical or obstetric indications for labor induction but had an unripe cervix between May 1997 and November 1999. They were randomly assigned to receive either oral or vaginal misoprostol for cervical ripening. The initial dose was 200/zg oral and 50/*g vaginally. After two doses the amount of medication was increased to 300 ~*g orally and 100 ~zg vaginally. The protocol limited the number of doses to a maximum of six. Doses of medication were given at 6-hour intervals. The final patient groups included 417 patients receiv©2002 by the American College of Obstetricians and Gynecologists Published by Elsevier Science Inc. 1085-6862/02/$600
Commentary: The reports on the use of misoprostol for cervical ripening continue to indicate the effectiveness of this prostaglandin E1 analog. This study attempted to compare the results of oral and vaginal administration of the medication. Both were equally effective in cervical ripening, but there were more interventions in the oral group than the vaginal group. The numbers were small in both intervention groups, but the difference between the oral and vaginal administration would seem to indicate, as the authors suggested, that the vaginal route is preferred. There is no evidence to explain the difference, but the absorption from the gastrointestinal tract may play an unknown factor in the blood levels or there may be some other explanation. Regardless of the reason, it is apparent from the study that differences do exist. Physician preference was also reported as a reason for stopping the medication. This indication is interesting and should have further explanation. Why would a physician stop the medication unless there was a reason? ACOG Practice Bulletin No. 10, November 1999, entitled Induction of Labor, contains detailed information on the use of misoprostol for cervical ripening. Although the bulletin was produced based on the data available more than 2 years ago, it is still appropriate for today. One strong caveat in
the document that should be emphasized is the avoidance of the use of • misoprostol in women with a prior cesarean birth.
Oral vs. Vaginal Misoprostol ShettyA,Danidian P, TempletonA. A comparison of oral and vaginal misoprostoltablets in inductionof labour at term. BrJ Obstet Gynaeco12001;108:238-43. Synopsis" In this report, the authors randomly assigned women to receive 50/zg of misoprostol orally or vaginally for five doses at 4-hour intervals. Their objective was to compare the efficacy of comparable doses of the medication for the induction of labor. There were 245 women in the study. All of the participants had a medical or obstetric indication for induction of labor and had a single fetus in the cephalic position. The main outcome was the length of time from onset of induction to successful vaginal delivery. There were 122 women who received the medication orally and 123 who used the medication vaginally. The mean induction to delivery time for the vaginal misoprostol group was 10.1 hours earlier than for the oral medication group (17.8 versus 27.9 hours). There were eight failed inductions in the oral group and three in the vaginal group. No differences in the mode of delivery or analgesic requirements were noted between the groups. The incidence of fetal distress, which required an operative abdominal or vaginal delivery, was significantly higher in the vaginal group. Neonatal outcomes were similar in the two groups. The authors conduded that either vaginal or oral misoprostol effectively induced labor. The vaginal route led to a more rapid delivery, but had a higher incidence of fetal distress and thus the oral route may be preferable. Level I.
Commentary: Like the previous article, this study attempted to compare the oral and vaginal routes of administration of this prostaglandin E1 analog for the induction of labor. As reported in most studies, the medication is effective when used for labor
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induction and/or cervical ripening. In this study the doses used were much less than those in the previous report, with a maximum of 50/zg. This report has a significant problem, however. They mixed patients who were having their first pregnancy with those who had delivered previously. They also did not report the length of the pregnancies and thus, we have no idea if the patients were early or at term. They also failed to describe the Bishop scores or to define any contraindications to the study except for specifying that patients should have a singleton fetus in cephalic presentation in an unscarred uterus. These oversights leave us with little actual information on which to base our interpretation of the authors' conclusion. If all they were interested in determining was the fact that oral and vaginal prostaglandins work, then they succeeded. If they wished to give us a better understanding of the factors involved, they left out too much information for any conclusion. It is important in studies such as this to be certain that the two groups are comparable and to limit entry to subjects who meet specific requirements of the protocol. The better the definition in the protocol, the better the interpretation of data.
Varicella Vaccine Exposure Dur:ng Pregnancy Shields KE, Galil K, SewardJ, Sharrar RG, CorderoJF, SlaterE. Varicellavaccineexposure during pregnancy:Data from the first 5 years of the pregnancy registry. Obstet Gyne¢o12001;98:14-9. Synopsis: From March 1995 through March 2000, a total of 362 women were identified from a pregnancy registry as having received varicella vaccine during the pregnancy. These women were evaluated to assess the risk of congenital varicella syndrome or other birth defects in the children of these pregnancies. Ninety-two women who were known to be varicelia seronegative received their first dose of the vaccine during the first or second trimester of the pregnancy. No cases of congenital varicella syndrome were identified among the 56 live births. Among all of the prospective reports of live births, congenital 4 • ACOG
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anomalies were noted in five but none of these was compatible with the varicelia syndrome. Thus the authors concluded from their limited data that the inadvertent vaccination of pregnant women with varicella did not appear to increase the risk of congenital varicella syndrome. Level III.
maintained by Merck & Co., West Point, Pennsylvania.
Perinatal Outcomes in Gestational Diabetes Pennison EH, Egerman RS. Perinatal outcomes in gestationaldiabetes:A comparison of criteria for diagnosis. Am J Obstet Gyneco12001; 184:1118 -21.
Commentary: Varicella is a common communicable disease among children that is readily preventable with appropriate immunization. When the wild virus occurs in a woman who is pregnant and not immune, the virus may affect the fetus with the resultant congenital varicella syndrome. This syndrome includes effects on many organs, as all organs of the body are susceptible. The infants may have microcephaly, chorioretinitis, cataracts, muscle atrophy, and hypoplasia of the hands and feet, among other anomalies. In March 1995, a live-attenuated viral vaccine was licensed and recommended for immunization. The company, Merck, established a pregnancy registry to monitor all women who received the vaccine during pregnancy or within the 3 months before pregnancy. This report is based on this registry. It is reassuring to see the results that they have reported. However, it is too early to accept that the vaccine can cause no harm. As with any registry, the reliability of the information is dependent on what data are sent to the registry. Congenital anomalies occur in approximately 2% of all births and, as such, may or may not be reported. The reliability of the registry is dependent on the physicians' knowledge of whether a vaccine was given and on voluntary reporting, which is rarely 100%. The authors reported that a number of women who had an abortion were not available for study. Fifty-six live births is too low to draw any firm conclusions. It is still best to follow the recommendations that women who are pregnant or plan to become pregnant within the next 3 months should not be vaccinated. However, if a vaccination occurs during this time the results of the pregnancy should be reported to the Pregnancy Registry for Varivax,
• M a r c h 2002
Synopsis: This study was designed to evaluate the outcome of pregnancies in women with the diagnosis of gestational diabetes as defined by the A C O G - N a t i o n a l Diabetes Data Group (NDDG) recommendations when compared with the American Diabetes Association (ADA) criteria. They identified 242 women between 1995 and 1999 for the study. These women were divided into three groups. Group one comprised euglycemic control patients; patients in group two were diagnosed as having gestational diabetes by the N D D G criteria; patients in group three had gestational diabetes according to the ADA criteria. Primary outcomes were cesarean delivery rates, preeclampsia, and macrosomia. The three groups were similar in demographic factors. When the frequencies of the primary outcomes were compared, the three groups had no significant differences. Neonatal hypoglycemia was more frequent in the ADA group (23.3%) and the N D D G group (16.2%) than in the controls. Thus they questioned whether there are benefits in defining an additional high-risk population by the ADA criteria. Level II-3.
Commentary: The stated purpose of this article was m compare perinatal outcomes between two recommended diagnostic criteria for gestational diabetes. In the ADA criteria, the diagnosis is made when two or more abnormal findings occur in a 3-hour glucose tolerance test when the glucose level is 95 mg/dL while fasting, 180 mg/dL or higher at 1 hour, 155 mg/dL at 2 hours, and 140 mg/dL at 3 hours. For the N D D G criteria, the diagnosis is based on two or more abnormal findings when the glucose level is 105 mg/dL or higher while fasting, 190 ©2002 by the AmericanCoUegeo! Obstetriciansanti Gynecologists Published bv Elsevier Science inc. 1085-6862/02/~6.00
mg/dL at 1 hour, 165 mg/dL at 2 hours, and 145 mg/dL at 3 hours. The ADA-suggested levels presented were first proposed by Carpenter and Coustan in an article in 1982, but were not adopted by the ADA until 1998. It is apparent to this Editor that this issue needs to be re-addressed by both ACOG and the ADA. The two major organizations that deal with this potentially dangerous disease need to be consistent in their educational materials and recommendations. The authors found little difference in the management of the patients and the outcome of the infant using either group's diagnostic criteria. What the significance of this finding is needs to be evaluated. As the authors suggest, further large-scale studies need to be undertaken to determine the most appropriate diagnostic criteria.
Pregnancy Complications andMaternal Risk of Ischemic Heart Disease
Commentary: The main question in this study is which is the etiologic factor and which is the result. It is apparent from such a large study that some relationship does exist. What is not apparent is whether the factor that caused the three related conditions was the initiating factor for the ischemic heart disease. It would seem, as the authors indicated, that there is a strong genetic link between the risk of ischemic heart disease and birth weight of the infant. The details of this linkage are unclear. Because this is a retrospective observational study, some predisposing factors may have been overlooked that could be confounding variables. One such variable recognized by the authors is the incidence of smoking. The most valid conclusion is that a low birth weight infant may be a warning signal that some other conditions may exist that could adversely affect the mother later in life.
ieonatal Screening or Cystic Fibrosis
Smith GCS, Pell JP, Walsh D. Pregnancy complications and maternal risk of ischaemic heart disease: A retrospectivecohort study of 129,290 births. Lancet 2001;357: 2002-6.
CiskeDJ, HaavistoA, LaxovaA, RockLZM, FarrellPM. Geneticcounselingand neonatal screeningforcysticfibrosis:An assessmentof the communication process, Pediatrics 2001;107:699-705.
Synopsis: This study was undertaken to investigate the possible relationship between pregnancy conditions that are associated with low birth weight and whether they are related to the later development of ischemic heart disease. They reviewed the discharge data of 129,920 eligible deliveries of singleton live births between 1981 and 1985 in Scotland. Linkage was made to the mothers' subsequent admissions and deaths from ischemic heart disease or any other cause in the 15-19 years of follow-up. They found that delivering a infant with low birth weight (lowest quintile), delivering preterm, and preedampsia were all associated with an increased risk of admission to the hospital for treatment and even death from ischemic heart disease. They concluded that complications of pregnancy linked to low birth weight are associated with an increased risk of ischemic heart disease in the mother. Level II-3.
Synopsis: The purpose of this study was to evaluate the effectiveness of counseling and communication of health care workers and parents of children who were heterozygous carriers for cystic fibrosis. The state of Wisconsin initiated a voluntary, routine, statewide screening program in 1994. There were 483 infants identified who were cystic fibrosis carriers, and parents of 183 agreed to participate in a questionnaire assessing their newborn screening program experiences and their knowledge of the genetics of cystic fibrosis. Follow-up telephone interviews were also conducted. There were t 38 questionnaires completed, and 123 of the 138 had a telephone interview. O f the 138 responses, 88.3% of the parents understood that their child was a carrier for cystic fibrosis, but 15.4% were unsure if carrier status could cause the illness. Only 57% knew that there was a 25% chance that their child could have a
@2002 by the American College of Obstetricians and Gynecologists Published bv ElsevierScience Inc. 1085-6862/02/$6.00
child with cystic fibrosis if he or she had a mate that was a carrier. Parents who had received genetic counseling responded correctly more frequendy than those who had not. The authors concluded that genetic counseling is imperative if a newborn screening program is to be successful. They noted that research is needed into the most effective form of communication to exiglain the situation to parents. Level II-3.
Commentary: This study was undertaken to evaluate a newborn screening program and the related communication and education that occurred as genetic counseling. Their results indicate that even with a detailed program there are still misunderstandings and lack of understanding. This article serves to amplify the issue of genetic counseling and the need to assure an adequate program. In the fall of 2001, ACOG distributed a report on cystic fibrosis and patient educational consent materials. ACOG's educational documents will become an important aspect of prenatal testing. The article that has been reviewed has many flaws. The numbers of respondents is low and the goal of assessing knowledge is difficult to evaluate. However, the point the study makes is that even with counseling, the parents did not always understand or comprehend what was being presented. This lack of comprehension can be the source of later problems.
Peripartum Cardiomyopathy Elkayam U, Tummala PP, Rao K, Akhter MW, KaraalpIS, Wani OR, et al. Maternal and fetal outcomesof subsequent pregnanciesin womenwith peripartumcardiomyopathy. N Engl J Med 2001;344:1567-71. Synopsis: This is a report of a survey of members of the American College of Cardiology. They were attempting to identify the subsequent outcomes of pregnancies in women who developed peripartum cardiomyopathy in a prior pregnancy. The survey identified 44 women in whom the diagnosis was made; they had 60 subsequent pregnancies. The authors then reviewed the medical records and inter-
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viewed the patients and their physicians. Among the first pregnancies after the diagnosis, 28 occurred in women in whom left ventricular (LV) function had returned to normal and 16 in women with persistent LV dysfunction. In the subsequent pregnancies, symptoms of heart failure occurred in 21% of women with normal LV function and 44% of women with persistent LV dysfunction. The mortality rate was 0 in the 28 but was 19% in those with persistent LV dysfunction. This latter group also had a higher incidence of premature delivery (37% compared with 11%). The authors concluded that a subsequent pregnancy in a patient with peripartum cardiomyopathy is associated with a significant reduction in LV function that can cause serious complications in the subsequent pregnancy and may even lead to death. Level III. •
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(CPD) in situations in which the cervix was completely dilated and the labor progressing well but the head failed to descend during a specified time, usually 2 hours. Before this period, the patient was in active labor. In the last 20 years, physicians have been less willing to let patients reach the status of CPD and thus have interrupted the labor process earlier. To address this we have established the diagnosis of "failure to progress." It is not the point of this review to debate the merits of this diagnosis or whether the patient who is not progressing is going to have CPD if allowed to labor longer. The diagnosis is here and it is used with increasing frequency. Finally, the authors conduded that the risk factors, rather than labor induction, are the etiology of the increased risk of cesarean delivery. It could also be concluded that pregnancy is also a cause. After all, what does nulliparity have that makes it a risk factor other than the patient is pregnant?
D
Commentary: Peripartum cardiomyopathy is a rare condition in pregnant women. When it occurs the patient presents with the signs and symptoms of heart failure. The etiology is unknown and because of the limited number of cases that any one physician may see, information is scarce. This study has, by survey and interview, given us some insight into the problem. The important finding is that even in those whose LV function has returned to normal, there is an incidence of repeated problems. In women whose LV dysfunction is not resolved, the potential exists for a major complication that can be associated with death.
Induction of Labor and Rates of Cesarean Delivery Alexander JM, Mclntire DD, Leveno KJ. Prolonged pregnancy: Induction of labor and cesareanbirths. Obstet Gynecol2001; 97:911-5.
Synopsis: A
42nd week. Spontaneous labor occurred in 687 (52%) of the women before the induction was initiated. When these women were compared with those who had induced labor, the induced women were slightly more likely to be nulliparous (54% compared with 49%) and had longer labor with more frequent use ofepidural anesthesia. Cesarean deliveries were more common in those women who underwent an induction than in those who went into spontaneous labor (19% versus 14%). The major difference in the two rates was the result of an increased determination of"failure to progress." When the authors corrected for the risk factors of nulliparity, undilated cervix, and epidural anesthesia, they found that it was the risk factors and not the induction that was the reason for the increased incidence of cesarean delivery. Level II-1.
total of 1325 women who were at 41 weeks' gestation or beyond were included in this prospective observational study of induction of labor for post-date pregnancy. The inductions were scheduled at the
Commentary:. This artide was difficult to evaluate. If more than 50% of the patients went into spontaneous labor, then it would seem that their criteria for "prolonged pregnancy" was inaccurate. In their methods they compared ultrasound with measurements of the fetus and the last menstrual period to determine the actual gestation. They did not describe how or if the ultrasound before 26 weeks was obtained earlier in some and later in others, nor did they discriminate by when the early determination of fetal age was made. The study would have been better had this information been available. Their finding that nulliparity and an undilated cervix were associated with an increased incidence of cesarean delivery would not be unexpected, as these two conditions are associated with a higher incidence of cesarean delivery in patients who are not diagnosed with a prolonged pregnancy. The association with epidural anesthesia needs further clarification. There is much debate about the role of epidural anesthesia in the indications for cesarean delivery. The problem with this study and others that use the diagnosis of "failure to progress" is that this diagnosis is imprecise and subject to much interpretation. Older studies always referred to cephalo-pelvic disproportion
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Safety of YBAC Blanchette H, Blanchette M, McCabe J, VincentS. Is vaginalbirth aftercesareansafe? Experienceat a communityhospital. Am J Obstet Gyneco12001;184:1478-87. Synopsis: This 4-year (1996-1999) prospective cohort study was conducted with 1481 women who had had a prior cesarean delivery. In this cohort, 727 elected to have a repeat cesarean delivery and 754 attempted a trial of labor. A successful vaginal birth after cesarean (VBAC) delivery occurred in 577 of the 754 patients. However, they had 12 ruptured uteri (1.6%). Eleven of the 12 were associated with either induction or augmentation of labor. In reviewing the rate of VBAC in their hospital in last 2 years of the study as a subgroup, the authors found that the rate had dedined significantly while the elective repeat cesarean rate had increased. Thus they concluded that promoting a trial of labor did not significantly reduce their elective repeat cesarean rate or increase their VBAC rate and that in the last 2 years of the study the trends reversed. The role of uterine rupture with fetal loss was probably a factor in this reversal. Level II-1.
©2002 by theAmerican Collegeof Obstetriciansand Gynecologists Pllhli~hoff hv Fl~f=vi~r griJ=nr~ Inr lflRh-RRRglNgI~RNN
Conunentary: A 1.6% uterine rupture rate is a significant complication of attempted vaginal birth after having had a prior cesarean delivery. As a result, the authors believe that this influenced the physicians in the hospital to change their recommendation for VBAC. There is no evidence in the study to support this impression but the data certainly show that a change took place in the last 2 years of the 4-year study. A conclusion of the study is that induction of labor and possibly augmentation are contributing factors and that neither should be considered in these patients. Dr. EIliott Main, in a discussion of this study, presented a summary of the rate of uterine rupture in five additional studies with a high of 5.4% associated with induced labor. These data as well as other reports should make the use of oxytocic agents in these patients limited. As Dr. Main states, "Don't push it."
Dangers of VBAC and Labor Induction Sims EJ, Newman RB, HulseyTC. Vaginal birth aftercesarean:To induce or not to induce. Am J Obstet Gynecol 2001;184: 1122-4. Synopsis: This study was undertaken to determine the impact of labor induction in women who were candidates for a VBAC. The format was a prospective observational analysis performed on 505 women between 1997 and 1999. There were three cohorts in the study: those without a trial of labor (269), those with spontaneous onset of labor (179), and those with induced labor (57). The vaginal delivery rate was highest in the spontaneous labor group (77.1% versus 57.9%). Uterine scar separation occurred more frequently in the induced labor patients (7%) than in the spontaneous labor group (1.5%). The use ofoxytocin in the spontaneous labor group was associated with a reduced likelihood of a successful vaginal delivery. Factors that appeared to affect a successful trial of labor included prior vaginal delivery, prior successful VBAC, and a favorable cervix. In patients without a prior vaginal delivery, induction of labor was accompanied with a greater incidence of
repeat cesarean delivery (51.1%) when compared with those who had spontaneous onset of labor (25.5%). They concluded that induction of labor in a woman who had a previous cesarean delivery and who is attempting a trial of labor is associated with a significantly increased risk of materhal morbidity and failure to deliver vaginally. Level II-3.
Commentary: This article also highlights the risk of uterine rupture in patients who require induction of labor in an attempt to have a VBAC. The authors of this study have presented a concise report comparing patients in spontaneous labor and those with induced labor. Their data support other reports that also indicate the use of uterine stimulation is a significant risk. Although induction of labor may be appropriate for many reasons, this study does not discuss why induction was attempted. Why the induction had been indicated would shed more light on the findings and give the reader an important additional piece of information to include in the decision-making process.
Antenatal Corticosteroids for Women at Risk of Preterm Delivery Guinn DA, AtkinsonMW, SullivanL, et al. Singlevs weeklycoursesofantenatal corticosteroids for women at risk of preterm delivery: A randomized controlled trial. JAMA 2001;286:1581-7. Synopsis: The objective of this study was to evaluate the efficacy of weekly administration of antenatal corticosteroids as compared with a single dose when evaluating the incidence of neonatal morbidity and complications. A randomized, double-blind, placebo-controlled study was conducted in 13 centers from February 1996 through April 2000. All patients received a single dose of either betamethasone 12 mg intramuscularly (IM) repeated once in 24 hours for two doses, or dexamethasone 6 mg IM every 12 hours for four doses. Pa-
tients who were undelivered 1 week later were given additional betamethasone or placebo every week until 34 weeks or delivery. The two groups were then compared and it was found that the weekly courses of the antenatal corticosteroids did not reduce the neonatal morbidity. Thus, the authors recommended that corticosteroids not be prescribed routinely for women at risk for preterm delivery. Level I.
Commentary: For many years, the use of antenatal corticosteroids has been advocated for the preterm laboring patient to reduce the incidence of neonatal complications, specifically respiratory distress syndrome (RDS). In 1994, the National Institute of Child Health and Human Development (NICHD) convened a consensus conference to address this issue. The consensus was that the use of antenatal corticosteroids could reduce the incidence of RDS in infants born between 29 and 34 weeks' gestation. They made several recommendations as to how to administer the medications. The initial doses used in this study followed those recommendations. Repeated doses were recommended only on an as-needed basis. In this multicenter study of 502 patients, the initial dose did appear to offer benefits to the infants who received the initial treatment but did not show significant benefit to those on the weekly protocol. Since the authors report on studies that indicate multiple courses are associated with cognitive or motor deficits, they ended the study early. Based on the data, this was an appropriate action as it is unlikely that repeated doses would have improved the composite morbidity when compared with a single treatment regime; thus, repeated doses should not be considered. Readers may wish to review ACOG's position on this issue in
ACOG Committee Opinion No. 210, October 1998, from the Obstetric Practice Committee, entitled Antenatal Corticosteroid Therapy for Fetal Maturation. a
02002 by the American College of Obstetricians and Gynecologists Published by Elsevier Science Inc. 1085-6862/02/$6.00
March 2002 • ACOG CLINICAL REVIEW • 7
Increased Neonatal Morbidity With Vaginal Delivery in Breech Birth
tures in women on HRT, but that this improvement may be attenuated in older women. Level I. Ralph W. Hale, M D
HerbstA, Thorngren-JemeckK. Modeof deliveryin breechpresentationat term:Increased neonatalmorbiditywithvaginaldelivery.Acta O b ~ Gyn~ol Scand2001;80:731-7.
Synopsis:This study was undertaken to compare the neonatal outcome of planned vaginal delivery in singleton breech presentations with that of a planned cesarean delivery. A retrospective study including 1050 patients was developed. A vaginal delivery was planned in 699 (670/0) and carried out in 603; a cesarean delivery was planned and carried out in 327 (31%). They compared the two groups as to acidemia at birth, low Apgar scores, neonatal neurological morbidity, and long-term sequelae. Acidemia at birth, Apgar scores < 7 at 5 minutes, and referral to the neonatal intensive care unit were higher in the planned vaginal delivery than in the cesarean delivery patients. They found that the rate of neonatal neurological morbidity could be reduced by planned cesarean delivery for a breech presentation. Level 11-3.
Commentary:In this Swedish study, the authors compared the results of a planned vaginal delivery of a term breech with that of a planned cesarean delivery. Because the study was retrospective, comparison of the cases was difficult. However, in the overall review they found that a vaginal delivery increased the risk of acidemia, low 5-minute Apgar score, and neonatal neurological morbidity. All of these results are important and would lead to the conclusion that elective cesarean delivery is the preferred route of delivery for a term breech presentation. It was not clear from this report whether version was attempted and, if so, what their success rate and the results were for that group of infants. In addition, the study included no comparison with nonplanned breech deliveriesand no review of the skill of the obstetricians. All of these factors need to be considered, but still do not negate the fact that the planned cesarean delivery was safer for the infant. 8
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HRT for Prevention of Nonvertebral Fractures TorgersonDJ, Bell-SyerSEM. Hormonereplacement therapy and prevention of nonvertebralfractures.JAMA2001;285:2891-7. Synopsis: The purpose of this study was to evaluate the impact of hormonal replacement therapy (HRT) on the reduction of fractures in postmenopausal women. The authors performed a meta-analysis of articles appearing in MEDLINE, Embase, Science Citation Index, and Cochrane databases from 1997 to 2000. O f the 70 initially identified studies, 22 were included in the analysis. They also contacted authors of studies to determine if other data were available and they reviewed unpublished data. The combined data from all of the trials suggested a significant reduction of fractures by 20% to 30% in HRT users. They then divided the data into three specific subgroups for analysis. First was the effect of age, second was the effect of treatment length, and third was the differential effect of HRT on fracture type. In the first group, 14 trials among women under age 60 that showed an approximate 35% reduction in fractures and 8 trials of women over 60 showed a 12% nonsignificant reduction. Trials of 3 years or more did not have an enhanced effect compared with those of less than 3 years. They were able to isolate hip and wrist fractures from some of the data and show a reduction of approximately 50% in women younger than 60 but less in women older than 60. They had no information on why the effect of HRT on women older than 60 was reduced, but offered some explanations based on the HERS data, which indicate that obese women may respond less well to HRT although some later data may negate this. They indicated that their review did not prove that HRT is ineffective in older women, but that there was an absence of evidence. The authors concluded that there is a statistical reduction in nonvertebral frac-
March 2002
Commentary: This artide generated a lot of media attention, most of which concentrated on the failure of HRT to protect against nonvertebral fractures. Some newspapers indicated that the use of HRT is now seriously questioned. I have studied this JAMA report extensively and I cannot find anywhere that the authors stated this as a fact. What the authors stated was that when HRT is started before age 60, nonvertebral fractures were reduced, and that this effect may be attenuated when HRT is begun after age 60. However, the authors made this statement without sufficient evidence. In fact, they stated that there are limited studies. When evidence is absent, it is better not to make any conclusion. By insinuating no effect and thus fueling the misinformation of the media, these authors have done a disservice to the women who are or may be on estrogens as treatment for prevention of osteoporosis. The media have tried to sensationalize this statement. One headline read: "Hormone therapy: Doubts grow." In contrast, in the August 15, 2001, issue ofJAMA, a study indicated a positive effect of estrogens for improving bone density in frail women 75 years of age and older but did not get the same press coverage. What is also absent from the JAMA article is that no report was based on vertebral fractures or vertebral osteoporosis. In this regard, the article and its interpretation are missing a major component of the battle against osteoporosis. The authors needed to make this much clearer in their presentation and the editors of JAMA should have insisted on such clarification. The essence of the report is that HRT does help women who initiate therapy before age 60 in preventing nonvertebral fractures. Nothing else should be implied or stated.
Antibiotic Prophylaxis to Prevent GTI CrowleyT, LowN, TurnerA, HarveyI, Bidgood K, Homer P. Antibioticprophylaxisto prevent post-abortal upper genital tract in©2oo2 by the AmericanCollegeof Obstetriciansand Gy'necologists
Publishedby ElsevierScience Inc. 1085-6862/02/$6.00
ACOGCLINICALREVIEW TO EXPAND Because of numerous requests from our subscribers, ACOG Clinical Review has increased its publication frequency to 10 issues per year in 2002. This way we hope to be better able to cover the large number of publications in our specialty. We thank the members whose response to this publication has been overwhelmingly positive. We are also appreciative of our publisher, Elsevier Science, Inc., who is making this expansion possible. With the new expansion, ACOG has selected a new editor, Dr. Morton Stenchever, to serve as the Editor of the series and the former editor, Dr. Ralph Hale, will now serve as Associate Editor.
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Ralph W. Hale, M D Editor
Oral and Vaginal Misoprostol Carlan SJ, BouldinS, BlustD, O~BrienWF. Safetyand efficacyof misoprostolorallyand vaginally: A randomized trial. Obstct Gyneco12001;98:107-12. Synopsis: This study included 1004 women with a singleton fetus who had medical or obstetric indications for labor induction but had an unripe cervix between May 1997 and November 1999. They were randomly assigned to receive either oral or vaginal misoprostol for cervical ripening. The initial dose was 200/zg oral and 50/*g vaginally. After two doses the amount of medication was increased to 300 ~*g orally and 100 ~zg vaginally. The protocol limited the number of doses to a maximum of six. Doses of medication were given at 6-hour intervals. The final patient groups included 417 patients receiv©2002 by the American College of Obstetricians and Gynecologists Published by Elsevier Science Inc. 1085-6862/02/$600
Commentary: The reports on the use of misoprostol for cervical ripening continue to indicate the effectiveness of this prostaglandin E1 analog. This study attempted to compare the results of oral and vaginal administration of the medication. Both were equally effective in cervical ripening, but there were more interventions in the oral group than the vaginal group. The numbers were small in both intervention groups, but the difference between the oral and vaginal administration would seem to indicate, as the authors suggested, that the vaginal route is preferred. There is no evidence to explain the difference, but the absorption from the gastrointestinal tract may play an unknown factor in the blood levels or there may be some other explanation. Regardless of the reason, it is apparent from the study that differences do exist. Physician preference was also reported as a reason for stopping the medication. This indication is interesting and should have further explanation. Why would a physician stop the medication unless there was a reason? ACOG Practice Bulletin No. 10, November 1999, entitled Induction of Labor, contains detailed information on the use of misoprostol for cervical ripening. Although the bulletin was produced based on the data available more than 2 years ago, it is still appropriate for today. One strong caveat in
the document that should be emphasized is the avoidance of the use of • misoprostol in women with a prior cesarean birth.
Oral vs. Vaginal Misoprostol ShettyA,Danidian P, TempletonA. A comparison of oral and vaginal misoprostoltablets in inductionof labour at term. BrJ Obstet Gynaeco12001;108:238-43. Synopsis" In this report, the authors randomly assigned women to receive 50/zg of misoprostol orally or vaginally for five doses at 4-hour intervals. Their objective was to compare the efficacy of comparable doses of the medication for the induction of labor. There were 245 women in the study. All of the participants had a medical or obstetric indication for induction of labor and had a single fetus in the cephalic position. The main outcome was the length of time from onset of induction to successful vaginal delivery. There were 122 women who received the medication orally and 123 who used the medication vaginally. The mean induction to delivery time for the vaginal misoprostol group was 10.1 hours earlier than for the oral medication group (17.8 versus 27.9 hours). There were eight failed inductions in the oral group and three in the vaginal group. No differences in the mode of delivery or analgesic requirements were noted between the groups. The incidence of fetal distress, which required an operative abdominal or vaginal delivery, was significantly higher in the vaginal group. Neonatal outcomes were similar in the two groups. The authors conduded that either vaginal or oral misoprostol effectively induced labor. The vaginal route led to a more rapid delivery, but had a higher incidence of fetal distress and thus the oral route may be preferable. Level I.
Commentary: Like the previous article, this study attempted to compare the oral and vaginal routes of administration of this prostaglandin E1 analog for the induction of labor. As reported in most studies, the medication is effective when used for labor
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induction and/or cervical ripening. In this study the doses used were much less than those in the previous report, with a maximum of 50/zg. This report has a significant problem, however. They mixed patients who were having their first pregnancy with those who had delivered previously. They also did not report the length of the pregnancies and thus, we have no idea if the patients were early or at term. They also failed to describe the Bishop scores or to define any contraindications to the study except for specifying that patients should have a singleton fetus in cephalic presentation in an unscarred uterus. These oversights leave us with little actual information on which to base our interpretation of the authors' conclusion. If all they were interested in determining was the fact that oral and vaginal prostaglandins work, then they succeeded. If they wished to give us a better understanding of the factors involved, they left out too much information for any conclusion. It is important in studies such as this to be certain that the two groups are comparable and to limit entry to subjects who meet specific requirements of the protocol. The better the definition in the protocol, the better the interpretation of data.
Varicella Vaccine Exposure Dur:ng Pregnancy Shields KE, Galil K, SewardJ, Sharrar RG, CorderoJF, SlaterE. Varicellavaccineexposure during pregnancy:Data from the first 5 years of the pregnancy registry. Obstet Gyne¢o12001;98:14-9. Synopsis: From March 1995 through March 2000, a total of 362 women were identified from a pregnancy registry as having received varicella vaccine during the pregnancy. These women were evaluated to assess the risk of congenital varicella syndrome or other birth defects in the children of these pregnancies. Ninety-two women who were known to be varicelia seronegative received their first dose of the vaccine during the first or second trimester of the pregnancy. No cases of congenital varicella syndrome were identified among the 56 live births. Among all of the prospective reports of live births, congenital 4 • ACOG
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anomalies were noted in five but none of these was compatible with the varicelia syndrome. Thus the authors concluded from their limited data that the inadvertent vaccination of pregnant women with varicella did not appear to increase the risk of congenital varicella syndrome. Level III.
maintained by Merck & Co., West Point, Pennsylvania.
Perinatal Outcomes in Gestational Diabetes Pennison EH, Egerman RS. Perinatal outcomes in gestationaldiabetes:A comparison of criteria for diagnosis. Am J Obstet Gyneco12001; 184:1118 -21.
Commentary: Varicella is a common communicable disease among children that is readily preventable with appropriate immunization. When the wild virus occurs in a woman who is pregnant and not immune, the virus may affect the fetus with the resultant congenital varicella syndrome. This syndrome includes effects on many organs, as all organs of the body are susceptible. The infants may have microcephaly, chorioretinitis, cataracts, muscle atrophy, and hypoplasia of the hands and feet, among other anomalies. In March 1995, a live-attenuated viral vaccine was licensed and recommended for immunization. The company, Merck, established a pregnancy registry to monitor all women who received the vaccine during pregnancy or within the 3 months before pregnancy. This report is based on this registry. It is reassuring to see the results that they have reported. However, it is too early to accept that the vaccine can cause no harm. As with any registry, the reliability of the information is dependent on what data are sent to the registry. Congenital anomalies occur in approximately 2% of all births and, as such, may or may not be reported. The reliability of the registry is dependent on the physicians' knowledge of whether a vaccine was given and on voluntary reporting, which is rarely 100%. The authors reported that a number of women who had an abortion were not available for study. Fifty-six live births is too low to draw any firm conclusions. It is still best to follow the recommendations that women who are pregnant or plan to become pregnant within the next 3 months should not be vaccinated. However, if a vaccination occurs during this time the results of the pregnancy should be reported to the Pregnancy Registry for Varivax,
• M a r c h 2002
Synopsis: This study was designed to evaluate the outcome of pregnancies in women with the diagnosis of gestational diabetes as defined by the A C O G - N a t i o n a l Diabetes Data Group (NDDG) recommendations when compared with the American Diabetes Association (ADA) criteria. They identified 242 women between 1995 and 1999 for the study. These women were divided into three groups. Group one comprised euglycemic control patients; patients in group two were diagnosed as having gestational diabetes by the N D D G criteria; patients in group three had gestational diabetes according to the ADA criteria. Primary outcomes were cesarean delivery rates, preeclampsia, and macrosomia. The three groups were similar in demographic factors. When the frequencies of the primary outcomes were compared, the three groups had no significant differences. Neonatal hypoglycemia was more frequent in the ADA group (23.3%) and the N D D G group (16.2%) than in the controls. Thus they questioned whether there are benefits in defining an additional high-risk population by the ADA criteria. Level II-3.
Commentary: The stated purpose of this article was m compare perinatal outcomes between two recommended diagnostic criteria for gestational diabetes. In the ADA criteria, the diagnosis is made when two or more abnormal findings occur in a 3-hour glucose tolerance test when the glucose level is 95 mg/dL while fasting, 180 mg/dL or higher at 1 hour, 155 mg/dL at 2 hours, and 140 mg/dL at 3 hours. For the N D D G criteria, the diagnosis is based on two or more abnormal findings when the glucose level is 105 mg/dL or higher while fasting, 190 ©2002 by the AmericanCoUegeo! Obstetriciansanti Gynecologists Published bv Elsevier Science inc. 1085-6862/02/~6.00
mg/dL at 1 hour, 165 mg/dL at 2 hours, and 145 mg/dL at 3 hours. The ADA-suggested levels presented were first proposed by Carpenter and Coustan in an article in 1982, but were not adopted by the ADA until 1998. It is apparent to this Editor that this issue needs to be re-addressed by both ACOG and the ADA. The two major organizations that deal with this potentially dangerous disease need to be consistent in their educational materials and recommendations. The authors found little difference in the management of the patients and the outcome of the infant using either group's diagnostic criteria. What the significance of this finding is needs to be evaluated. As the authors suggest, further large-scale studies need to be undertaken to determine the most appropriate diagnostic criteria.
Pregnancy Complications andMaternal Risk of Ischemic Heart Disease
Commentary: The main question in this study is which is the etiologic factor and which is the result. It is apparent from such a large study that some relationship does exist. What is not apparent is whether the factor that caused the three related conditions was the initiating factor for the ischemic heart disease. It would seem, as the authors indicated, that there is a strong genetic link between the risk of ischemic heart disease and birth weight of the infant. The details of this linkage are unclear. Because this is a retrospective observational study, some predisposing factors may have been overlooked that could be confounding variables. One such variable recognized by the authors is the incidence of smoking. The most valid conclusion is that a low birth weight infant may be a warning signal that some other conditions may exist that could adversely affect the mother later in life.
ieonatal Screening or Cystic Fibrosis
Smith GCS, Pell JP, Walsh D. Pregnancy complications and maternal risk of ischaemic heart disease: A retrospectivecohort study of 129,290 births. Lancet 2001;357: 2002-6.
CiskeDJ, HaavistoA, LaxovaA, RockLZM, FarrellPM. Geneticcounselingand neonatal screeningforcysticfibrosis:An assessmentof the communication process, Pediatrics 2001;107:699-705.
Synopsis: This study was undertaken to investigate the possible relationship between pregnancy conditions that are associated with low birth weight and whether they are related to the later development of ischemic heart disease. They reviewed the discharge data of 129,920 eligible deliveries of singleton live births between 1981 and 1985 in Scotland. Linkage was made to the mothers' subsequent admissions and deaths from ischemic heart disease or any other cause in the 15-19 years of follow-up. They found that delivering a infant with low birth weight (lowest quintile), delivering preterm, and preedampsia were all associated with an increased risk of admission to the hospital for treatment and even death from ischemic heart disease. They concluded that complications of pregnancy linked to low birth weight are associated with an increased risk of ischemic heart disease in the mother. Level II-3.
Synopsis: The purpose of this study was to evaluate the effectiveness of counseling and communication of health care workers and parents of children who were heterozygous carriers for cystic fibrosis. The state of Wisconsin initiated a voluntary, routine, statewide screening program in 1994. There were 483 infants identified who were cystic fibrosis carriers, and parents of 183 agreed to participate in a questionnaire assessing their newborn screening program experiences and their knowledge of the genetics of cystic fibrosis. Follow-up telephone interviews were also conducted. There were t 38 questionnaires completed, and 123 of the 138 had a telephone interview. O f the 138 responses, 88.3% of the parents understood that their child was a carrier for cystic fibrosis, but 15.4% were unsure if carrier status could cause the illness. Only 57% knew that there was a 25% chance that their child could have a
@2002 by the American College of Obstetricians and Gynecologists Published bv ElsevierScience Inc. 1085-6862/02/$6.00
child with cystic fibrosis if he or she had a mate that was a carrier. Parents who had received genetic counseling responded correctly more frequendy than those who had not. The authors concluded that genetic counseling is imperative if a newborn screening program is to be successful. They noted that research is needed into the most effective form of communication to exiglain the situation to parents. Level II-3.
Commentary: This study was undertaken to evaluate a newborn screening program and the related communication and education that occurred as genetic counseling. Their results indicate that even with a detailed program there are still misunderstandings and lack of understanding. This article serves to amplify the issue of genetic counseling and the need to assure an adequate program. In the fall of 2001, ACOG distributed a report on cystic fibrosis and patient educational consent materials. ACOG's educational documents will become an important aspect of prenatal testing. The article that has been reviewed has many flaws. The numbers of respondents is low and the goal of assessing knowledge is difficult to evaluate. However, the point the study makes is that even with counseling, the parents did not always understand or comprehend what was being presented. This lack of comprehension can be the source of later problems.
Peripartum Cardiomyopathy Elkayam U, Tummala PP, Rao K, Akhter MW, KaraalpIS, Wani OR, et al. Maternal and fetal outcomesof subsequent pregnanciesin womenwith peripartumcardiomyopathy. N Engl J Med 2001;344:1567-71. Synopsis: This is a report of a survey of members of the American College of Cardiology. They were attempting to identify the subsequent outcomes of pregnancies in women who developed peripartum cardiomyopathy in a prior pregnancy. The survey identified 44 women in whom the diagnosis was made; they had 60 subsequent pregnancies. The authors then reviewed the medical records and inter-
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viewed the patients and their physicians. Among the first pregnancies after the diagnosis, 28 occurred in women in whom left ventricular (LV) function had returned to normal and 16 in women with persistent LV dysfunction. In the subsequent pregnancies, symptoms of heart failure occurred in 21% of women with normal LV function and 44% of women with persistent LV dysfunction. The mortality rate was 0 in the 28 but was 19% in those with persistent LV dysfunction. This latter group also had a higher incidence of premature delivery (37% compared with 11%). The authors concluded that a subsequent pregnancy in a patient with peripartum cardiomyopathy is associated with a significant reduction in LV function that can cause serious complications in the subsequent pregnancy and may even lead to death. Level III. •
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(CPD) in situations in which the cervix was completely dilated and the labor progressing well but the head failed to descend during a specified time, usually 2 hours. Before this period, the patient was in active labor. In the last 20 years, physicians have been less willing to let patients reach the status of CPD and thus have interrupted the labor process earlier. To address this we have established the diagnosis of "failure to progress." It is not the point of this review to debate the merits of this diagnosis or whether the patient who is not progressing is going to have CPD if allowed to labor longer. The diagnosis is here and it is used with increasing frequency. Finally, the authors conduded that the risk factors, rather than labor induction, are the etiology of the increased risk of cesarean delivery. It could also be concluded that pregnancy is also a cause. After all, what does nulliparity have that makes it a risk factor other than the patient is pregnant?
D
Commentary: Peripartum cardiomyopathy is a rare condition in pregnant women. When it occurs the patient presents with the signs and symptoms of heart failure. The etiology is unknown and because of the limited number of cases that any one physician may see, information is scarce. This study has, by survey and interview, given us some insight into the problem. The important finding is that even in those whose LV function has returned to normal, there is an incidence of repeated problems. In women whose LV dysfunction is not resolved, the potential exists for a major complication that can be associated with death.
Induction of Labor and Rates of Cesarean Delivery Alexander JM, Mclntire DD, Leveno KJ. Prolonged pregnancy: Induction of labor and cesareanbirths. Obstet Gynecol2001; 97:911-5.
Synopsis: A
42nd week. Spontaneous labor occurred in 687 (52%) of the women before the induction was initiated. When these women were compared with those who had induced labor, the induced women were slightly more likely to be nulliparous (54% compared with 49%) and had longer labor with more frequent use ofepidural anesthesia. Cesarean deliveries were more common in those women who underwent an induction than in those who went into spontaneous labor (19% versus 14%). The major difference in the two rates was the result of an increased determination of"failure to progress." When the authors corrected for the risk factors of nulliparity, undilated cervix, and epidural anesthesia, they found that it was the risk factors and not the induction that was the reason for the increased incidence of cesarean delivery. Level II-1.
total of 1325 women who were at 41 weeks' gestation or beyond were included in this prospective observational study of induction of labor for post-date pregnancy. The inductions were scheduled at the
Commentary:. This artide was difficult to evaluate. If more than 50% of the patients went into spontaneous labor, then it would seem that their criteria for "prolonged pregnancy" was inaccurate. In their methods they compared ultrasound with measurements of the fetus and the last menstrual period to determine the actual gestation. They did not describe how or if the ultrasound before 26 weeks was obtained earlier in some and later in others, nor did they discriminate by when the early determination of fetal age was made. The study would have been better had this information been available. Their finding that nulliparity and an undilated cervix were associated with an increased incidence of cesarean delivery would not be unexpected, as these two conditions are associated with a higher incidence of cesarean delivery in patients who are not diagnosed with a prolonged pregnancy. The association with epidural anesthesia needs further clarification. There is much debate about the role of epidural anesthesia in the indications for cesarean delivery. The problem with this study and others that use the diagnosis of "failure to progress" is that this diagnosis is imprecise and subject to much interpretation. Older studies always referred to cephalo-pelvic disproportion
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Safety of YBAC Blanchette H, Blanchette M, McCabe J, VincentS. Is vaginalbirth aftercesareansafe? Experienceat a communityhospital. Am J Obstet Gyneco12001;184:1478-87. Synopsis: This 4-year (1996-1999) prospective cohort study was conducted with 1481 women who had had a prior cesarean delivery. In this cohort, 727 elected to have a repeat cesarean delivery and 754 attempted a trial of labor. A successful vaginal birth after cesarean (VBAC) delivery occurred in 577 of the 754 patients. However, they had 12 ruptured uteri (1.6%). Eleven of the 12 were associated with either induction or augmentation of labor. In reviewing the rate of VBAC in their hospital in last 2 years of the study as a subgroup, the authors found that the rate had dedined significantly while the elective repeat cesarean rate had increased. Thus they concluded that promoting a trial of labor did not significantly reduce their elective repeat cesarean rate or increase their VBAC rate and that in the last 2 years of the study the trends reversed. The role of uterine rupture with fetal loss was probably a factor in this reversal. Level II-1.
©2002 by theAmerican Collegeof Obstetriciansand Gynecologists Pllhli~hoff hv Fl~f=vi~r griJ=nr~ Inr lflRh-RRRglNgI~RNN
Conunentary: A 1.6% uterine rupture rate is a significant complication of attempted vaginal birth after having had a prior cesarean delivery. As a result, the authors believe that this influenced the physicians in the hospital to change their recommendation for VBAC. There is no evidence in the study to support this impression but the data certainly show that a change took place in the last 2 years of the 4-year study. A conclusion of the study is that induction of labor and possibly augmentation are contributing factors and that neither should be considered in these patients. Dr. EIliott Main, in a discussion of this study, presented a summary of the rate of uterine rupture in five additional studies with a high of 5.4% associated with induced labor. These data as well as other reports should make the use of oxytocic agents in these patients limited. As Dr. Main states, "Don't push it."
Dangers of VBAC and Labor Induction Sims EJ, Newman RB, HulseyTC. Vaginal birth aftercesarean:To induce or not to induce. Am J Obstet Gynecol 2001;184: 1122-4. Synopsis: This study was undertaken to determine the impact of labor induction in women who were candidates for a VBAC. The format was a prospective observational analysis performed on 505 women between 1997 and 1999. There were three cohorts in the study: those without a trial of labor (269), those with spontaneous onset of labor (179), and those with induced labor (57). The vaginal delivery rate was highest in the spontaneous labor group (77.1% versus 57.9%). Uterine scar separation occurred more frequently in the induced labor patients (7%) than in the spontaneous labor group (1.5%). The use ofoxytocin in the spontaneous labor group was associated with a reduced likelihood of a successful vaginal delivery. Factors that appeared to affect a successful trial of labor included prior vaginal delivery, prior successful VBAC, and a favorable cervix. In patients without a prior vaginal delivery, induction of labor was accompanied with a greater incidence of
repeat cesarean delivery (51.1%) when compared with those who had spontaneous onset of labor (25.5%). They concluded that induction of labor in a woman who had a previous cesarean delivery and who is attempting a trial of labor is associated with a significantly increased risk of materhal morbidity and failure to deliver vaginally. Level II-3.
Commentary: This article also highlights the risk of uterine rupture in patients who require induction of labor in an attempt to have a VBAC. The authors of this study have presented a concise report comparing patients in spontaneous labor and those with induced labor. Their data support other reports that also indicate the use of uterine stimulation is a significant risk. Although induction of labor may be appropriate for many reasons, this study does not discuss why induction was attempted. Why the induction had been indicated would shed more light on the findings and give the reader an important additional piece of information to include in the decision-making process.
Antenatal Corticosteroids for Women at Risk of Preterm Delivery Guinn DA, AtkinsonMW, SullivanL, et al. Singlevs weeklycoursesofantenatal corticosteroids for women at risk of preterm delivery: A randomized controlled trial. JAMA 2001;286:1581-7. Synopsis: The objective of this study was to evaluate the efficacy of weekly administration of antenatal corticosteroids as compared with a single dose when evaluating the incidence of neonatal morbidity and complications. A randomized, double-blind, placebo-controlled study was conducted in 13 centers from February 1996 through April 2000. All patients received a single dose of either betamethasone 12 mg intramuscularly (IM) repeated once in 24 hours for two doses, or dexamethasone 6 mg IM every 12 hours for four doses. Pa-
tients who were undelivered 1 week later were given additional betamethasone or placebo every week until 34 weeks or delivery. The two groups were then compared and it was found that the weekly courses of the antenatal corticosteroids did not reduce the neonatal morbidity. Thus, the authors recommended that corticosteroids not be prescribed routinely for women at risk for preterm delivery. Level I.
Commentary: For many years, the use of antenatal corticosteroids has been advocated for the preterm laboring patient to reduce the incidence of neonatal complications, specifically respiratory distress syndrome (RDS). In 1994, the National Institute of Child Health and Human Development (NICHD) convened a consensus conference to address this issue. The consensus was that the use of antenatal corticosteroids could reduce the incidence of RDS in infants born between 29 and 34 weeks' gestation. They made several recommendations as to how to administer the medications. The initial doses used in this study followed those recommendations. Repeated doses were recommended only on an as-needed basis. In this multicenter study of 502 patients, the initial dose did appear to offer benefits to the infants who received the initial treatment but did not show significant benefit to those on the weekly protocol. Since the authors report on studies that indicate multiple courses are associated with cognitive or motor deficits, they ended the study early. Based on the data, this was an appropriate action as it is unlikely that repeated doses would have improved the composite morbidity when compared with a single treatment regime; thus, repeated doses should not be considered. Readers may wish to review ACOG's position on this issue in
ACOG Committee Opinion No. 210, October 1998, from the Obstetric Practice Committee, entitled Antenatal Corticosteroid Therapy for Fetal Maturation. a
02002 by the American College of Obstetricians and Gynecologists Published by Elsevier Science Inc. 1085-6862/02/$6.00
March 2002 • ACOG CLINICAL REVIEW • 7
Increased Neonatal Morbidity With Vaginal Delivery in Breech Birth
tures in women on HRT, but that this improvement may be attenuated in older women. Level I. Ralph W. Hale, M D
HerbstA, Thorngren-JemeckK. Modeof deliveryin breechpresentationat term:Increased neonatalmorbiditywithvaginaldelivery.Acta O b ~ Gyn~ol Scand2001;80:731-7.
Synopsis:This study was undertaken to compare the neonatal outcome of planned vaginal delivery in singleton breech presentations with that of a planned cesarean delivery. A retrospective study including 1050 patients was developed. A vaginal delivery was planned in 699 (670/0) and carried out in 603; a cesarean delivery was planned and carried out in 327 (31%). They compared the two groups as to acidemia at birth, low Apgar scores, neonatal neurological morbidity, and long-term sequelae. Acidemia at birth, Apgar scores < 7 at 5 minutes, and referral to the neonatal intensive care unit were higher in the planned vaginal delivery than in the cesarean delivery patients. They found that the rate of neonatal neurological morbidity could be reduced by planned cesarean delivery for a breech presentation. Level 11-3.
Commentary:In this Swedish study, the authors compared the results of a planned vaginal delivery of a term breech with that of a planned cesarean delivery. Because the study was retrospective, comparison of the cases was difficult. However, in the overall review they found that a vaginal delivery increased the risk of acidemia, low 5-minute Apgar score, and neonatal neurological morbidity. All of these results are important and would lead to the conclusion that elective cesarean delivery is the preferred route of delivery for a term breech presentation. It was not clear from this report whether version was attempted and, if so, what their success rate and the results were for that group of infants. In addition, the study included no comparison with nonplanned breech deliveriesand no review of the skill of the obstetricians. All of these factors need to be considered, but still do not negate the fact that the planned cesarean delivery was safer for the infant. 8
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HRT for Prevention of Nonvertebral Fractures TorgersonDJ, Bell-SyerSEM. Hormonereplacement therapy and prevention of nonvertebralfractures.JAMA2001;285:2891-7. Synopsis: The purpose of this study was to evaluate the impact of hormonal replacement therapy (HRT) on the reduction of fractures in postmenopausal women. The authors performed a meta-analysis of articles appearing in MEDLINE, Embase, Science Citation Index, and Cochrane databases from 1997 to 2000. O f the 70 initially identified studies, 22 were included in the analysis. They also contacted authors of studies to determine if other data were available and they reviewed unpublished data. The combined data from all of the trials suggested a significant reduction of fractures by 20% to 30% in HRT users. They then divided the data into three specific subgroups for analysis. First was the effect of age, second was the effect of treatment length, and third was the differential effect of HRT on fracture type. In the first group, 14 trials among women under age 60 that showed an approximate 35% reduction in fractures and 8 trials of women over 60 showed a 12% nonsignificant reduction. Trials of 3 years or more did not have an enhanced effect compared with those of less than 3 years. They were able to isolate hip and wrist fractures from some of the data and show a reduction of approximately 50% in women younger than 60 but less in women older than 60. They had no information on why the effect of HRT on women older than 60 was reduced, but offered some explanations based on the HERS data, which indicate that obese women may respond less well to HRT although some later data may negate this. They indicated that their review did not prove that HRT is ineffective in older women, but that there was an absence of evidence. The authors concluded that there is a statistical reduction in nonvertebral frac-
March 2002
Commentary: This artide generated a lot of media attention, most of which concentrated on the failure of HRT to protect against nonvertebral fractures. Some newspapers indicated that the use of HRT is now seriously questioned. I have studied this JAMA report extensively and I cannot find anywhere that the authors stated this as a fact. What the authors stated was that when HRT is started before age 60, nonvertebral fractures were reduced, and that this effect may be attenuated when HRT is begun after age 60. However, the authors made this statement without sufficient evidence. In fact, they stated that there are limited studies. When evidence is absent, it is better not to make any conclusion. By insinuating no effect and thus fueling the misinformation of the media, these authors have done a disservice to the women who are or may be on estrogens as treatment for prevention of osteoporosis. The media have tried to sensationalize this statement. One headline read: "Hormone therapy: Doubts grow." In contrast, in the August 15, 2001, issue ofJAMA, a study indicated a positive effect of estrogens for improving bone density in frail women 75 years of age and older but did not get the same press coverage. What is also absent from the JAMA article is that no report was based on vertebral fractures or vertebral osteoporosis. In this regard, the article and its interpretation are missing a major component of the battle against osteoporosis. The authors needed to make this much clearer in their presentation and the editors of JAMA should have insisted on such clarification. The essence of the report is that HRT does help women who initiate therapy before age 60 in preventing nonvertebral fractures. Nothing else should be implied or stated.
Antibiotic Prophylaxis to Prevent GTI CrowleyT, LowN, TurnerA, HarveyI, Bidgood K, Homer P. Antibioticprophylaxisto prevent post-abortal upper genital tract in©2oo2 by the AmericanCollegeof Obstetriciansand Gy'necologists
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