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Biophysical profile scoring in the management of the postterm pregnancy: An analysis of 307 patients
Cervical carcinoma
Volume 154 Number 2
The present study indicated a difference in overall survival between younger and older women, which can be explained simply on the basis of more younger women presenting with invasive disease in the earlier stages. The survival patterns are similar, stage by stage, for younger and older women. Different treatment modalities between younger women and older women with less advanced invasive disease in favor of surgery for younger women is an expression of the general trend to treat less advanced invasive disease, in this age group, with operation rather than radiation. However, when survival patterns are compared between younger and older women with Stage IB disease, survival patterns with radical hysterectomy treatment and radiation are similar for both age groups. Thus neither treatment modality favors younger women. It is our opinion, on the basis of the present review, that there has been a recent slight increase in the proportion of younger women diagnosed as having invasive cervical carcinoma. The susceptibility to a screening program, the natural history of the disease, and the response to treatment are similar for younger and older women.
REFERENCES I. Walton RJ, Allen HH, Anderson, GH, et al. Cervical cancer
screening programs. Can Med AssocJ 1982;127:581. 2. Bourne RG, Grove WD. Invasive carcinoma of the cervix in Queensland. MedJ Aust 1983;1:156. 3. Green GH. Cervical cancer and cytology screening in New Zealand. Br J Obstet Gynaecol 1978;85:818. 4. Berkeley AS, LiVolsi VA, Schwartz PE. Advanced squamous cell carcinoma of the cervix with recent normal Papanicoulaou tests. Lancet 1980;2:375. 5. Rylander E. Negative smears in women developing invasive cervical cancer. Acta Obstet Gynecol Scand 1977;56:115. 6. Prempree T, Patanaphan V, Sewchand W, et al. The influence of patients' age and tumor grade on the prognosis of carcinoma of the cervix. Cancer 1983;51: 1764. 7. Paterson MEL, Peel KR, Joslin CAF. Cervical smear histories of 500 women with invasive cervical cancer in Yorkshire. Br Med J 1984;289:896. 8. Carmichael JA, Jeffrey JF, Steele HD, et al. The cytologic history of 245 patients developing invasive cervical carcinoma. AM J OBSTET GVNECOL 1984; 148:685. 9. Walton RJ, Blanchet M, Boyes DA, et al. Cervical cancer screening programs (Department of National Health and Welfare Task Force Report). Can Med Assoc J 1976;114:1003.
Biophysical profile scoring in the management of the postterm pregnancy: An analysis of 307 patients J. M. Johnson, M.D., C. R. Harman, M.D., I. R. Lange, M.D., and F. A. Manning, M.D. Winnipeg, Manitoba, Canada Management and outcome were reviewed in 307 consecutive postterm pregnancies assessed by biophysical profile scoring. Twice-weekly scores accurately differentiated normal fetuses from those at risk for intrauterine hypoxia. When the profile score is normal, waiting for spontaneous labor results in healthy neonates and a much lower cesarean section rate (15% versus 42% for "prophylactic" induction). Confident conservative management of postterm pregnancy is possible. (AM J OSSTET GVNECOL 1986;154:269-73.)
Key words: Postterm pregnancy, biophysical profile scoring Pregnancy persisting beyond 42 weeks of gestation or 294 days from the first day of the last normal menFrom the Division of Maternal-Fetal Medicine, Department of Obstetrics, G.vnecology, and Reproductive Sciences, University of Manitoba. Presented at the Forty-first Annual Meeting of The Society of Obstetricians and G.vnaecologists of Canada, Jasper, Alberta, Canada, June 10-15, 1985. Reprinl reque.5t.5: Dr. C. R. Harman, Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, Women's HO.5pital, 735 Notre Dame Ave., WinniPeg, Manitoba, Canada R3E OL8.
strual period is considered postterm and occurs in approximately 10% of all pregnancies.' Postterm pregnancy is associated with an increase in perinatal mortality, meconium-stained liquor, fetal distress in labor, and subsequent development and behavioral disturbances." Although it is a common problem, there is no unanimity of opinion regarding optimal management. Previous studies have reached little agreement as to when fetal jeopardy begins, how accurately the most endangered fetuses can be detected, or whether safe limits
269
270 Johnson et al.
February, 1986 Am J Obstet Gynecol
B.P.S.
Normal Score
~
Abnormal Score
Pelvic Assessment
~
Unfavourable
Favourable
for A.R.M.
I
(I) Repeat B.P.S.
1/2 Week
I
(II) Labour
Induced
(UI) Delivery by
Appropriate Route
Fig. 1. Management protocol and outcome groups:(I). Normal biophysical profile scoring (B.P.S.), spontaneous labor (A.R.M., artificial rupture of membranes): (I I), Normal biophysical profile scoring, labor induced: (III), Abnormal biophysical profile scoring, delivery by appropriate route.
can be established for the continuation of prolonged gestation.'-' Because of this uncertainty, many centers continue to follow a policy of uniform delivery when 42 weeks of gestation is reached. The potentially serious complications of postmaturity in some (10% to 20%) is seen as justification for the possibly unnecessary intervention in the remaining 80% to 90% of pregnancies. At our institution, antepartum fetal risk determination is based on a composite fetal biophvsical profile score.-··" The purpose of this study was to evaluate the benefits, if any, that are achieved when fetal biophysical profile scoring was used in the management of the patient with a postdate pregnancy. Two specific questions were addressed: (1) Can this method of assessment accurately detect the fetus at risk of intrauterine compromise because of postmaturity? (2) If the fetus continues to appear healthy according to the biophysical profile scoring, does withholding intervention beyond 42 weeks result in improved maternal outcome? If this practicable means of fetal assessment can accomplish both accurate intervention when the fetus is jeopardized and confident conservatism that protects the mother from the consequences of unnecessary intervention when the fetus is healthy, then its application in prolonged gestation would be validated. Material and methods
Criteria for inclusion in this prospective management study were as follows: single pregnancies with no
other complications, with firmly established gestational length of more than 294 days from the known last normal menstrual period. Dates were confirmed in all patients by early examination or early ultrasound studies or by both, and patients were excluded if the ultrasound findings on referral to the study group resulted in reassignment of dates. Biophysical profile scoring as described by Manning et al." was performed twice weekly on all patients. If all four ultrasound parameters (fetal movement, muscle tone, fetal breathing movements and amniotic fluid volume) were present, the biophysical profile scoring was considered to be normal, and a nonstress test was not done (biophysical profile scoring of 8/8'). If anyone of the first three ultrasound parameters listed was not present, a nonstress test was given, and if reactive, the biophysical profile scoring was again considered normal (biophysical profile scoring of 811 0). For scores of 6110 or 8110 in which amniotic fluid volume was the abnormal variable (pocket of <2.0 cm in vertical dimension, measured in two planes), the score was considered abnormal. Based on the biophysical profile score obtained at each visit, the patient was managed according to the protocol illustrated in Fig. 1. Three outcome groups were generated by the study (Table I). Group I consisted of patients with normal biophvsical profile scoring, followed without intervention until the spontaneous onset of labor. Group II patients also had normal scores until labor, which was induced with a cervix favorable for artificial rupture of membranes. Group III consisted of those in whom an abnormal score suggesting fetal compromise constituted a definite indication for delivery, which was undertaken within 24 hours by the appropriate route. For the purposes of analysis, group III was subdivided according to the depth of the largest amniotic fluid pocket available .' A fourth group of patients was generated because the attending physicians did not always follow the recommendations of the protocol. These patients all had a normal score at their last assessment but labor was induced "for dates only" despite a cervix unfavorable for artificial rupture of the membranes (Group IV). In all cases the last biophysical profile scoring before delivery was the score of preference in the analysis. Parameters of fetal perinatal morbidity were defined as (I) fetal distress in labor requiring emergency cesarean section, (2) 5-minute Apgar score of",,6, and (3) meconium aspiration requiring admission to neonatal intensive care. Apgar scores were assigned by independent observers. Intubation and suctioning were performed by a neonatologist or anesthetist on all infants with meconium present in amniotic fluid. The rate of cesarean section was calculated for each group.
Biophysical scoring in postterm pregnancy 271
Volume 154 Number 2
Table I. Management/outcome groups (n = 293) Mean birth weight Group
Biophysical profile scoring
I II III IV
Normal Normal Abnormal Normal
Description of delivery
Spontaneous labor Induced labor/favorable cervix Delivered because of fetal indications Induced for dates only
180 31 32 50
(gm)
Mean gestational length (days)
3997 3853 3664 3799
301 302 298 301
Table II. Incidence of perinatal morbidity Group I Morbidity
n
Cesarean section for fetal distress 5 min Apgar score of ",;:6 Meconium aspiration to intensive care nursery
6 3 4
I
Group II
%
n
3.3 1.6
2.2
I
% 3.2 3.2
o
Group III n
7 4 6
1
Group IV
%
n
22* 12.5* 19*
7
I
% 14t 2
I
o
*Significantly different from all other groups, p < 0.05 by X'. tSignificantly different from groups I and II, p < 0.05 by X'.
The four management/outcome groups were compared with use of X' contingency tables or Student's t test as was appropriate. A value of p < 0.05 was considered significant.
Results Over the 3-year period beginning September 1, 1981, 307 women referred for composite fetal assessment met the entry criteria. Fourteen of these women were delivered because of changes in maternal condition not related to postdatism and were excluded from further analysis. This resulted in a final study population of 293 patients, who had a total of 503 assessments. These patients were distributed among the four outcome/management groups, as shown in Table I. While differing in number, these groups did not differ significantly in distribution of maternal age, parity, or birth weight. Although patients in group III tended to require delivery sooner (for abnormal biophysical profile scoring that suggested fetal compromise) the range of time beyond 42 weeks at which the scoring became abnormal (0 to 12 days) rendered this difference statistically nonsignificant (Student's t test). All fetuses in group III were delivered within 24 hours of their abnormal biophysical profile scoring, whereas the majority of all other groups delivered within 4 days of their normal, last profile scoring. There were no stillbirths or perinatal deaths in the entire study population. There were significant differences in perinatal morbidity between groups (Table II). Fetuses in group III required cesarean section for fetal distress more often than any other group and had a total cesarean section rate of 37.5%. Fetuses in group III (delivered for abnormal biophysical profile scoring) accounted for 44% of low 5-minute Apgar scores and for 60% of neonatal admission to intensive care for
Table III. Cesarean section following normal biophysical profile scoring Group
Cesarean section for fetal distress
I
%
n
6 I
3.3 3.2
27 4
15 13
7
14*
21
42*
n
I. Spontaneous labor II. Induced labor favorable cervix IV. Induced for dates only
Total cesarean sections
t
%
*Significantly different from groups I and II, p < 0.01 by X'·
meconium aspiration. The frequency of cesarean delivery for fetal distress was also increased in group IV, but the frequency of low Apgar scores and serious meconium aspiration were not. Within group III (32 patients) perinatal morbidity was highest in fetuses with the lowest amniotic fluid volume. Among the 11 with overt oligohydramnios (largest pocket of fluid < 1.0 cm) four required cesarean section for fetal distress, eight had meconium in amniotic fluid, and six had meconium below their vocal cords, necessitating admission to the intensive care nursery for three of them. Six of the 11 had low Apgar scores at 1 minute and two at 5 minutes after birth. The nine fetuses with marginal fluid (pocket of 1 to 2 cm) had an average amniotic fluid volume of 1.6 cm. In this subgroup, two required delivery by cesarean section (there were no low 5-minute Apgar scores), and one was admitted to the intensive care nursery for meconium aspiration. In the subgroup with normal (>2.0 cm) amniotic fluid volume but abnormal biophysical profile scoring, six of 12 required cesarean section, two had low Apgar scores at 5 minutes, and two were ad-
272
Johnson et al.
February, 1986 Am J Obstet Gynecol
Table IV. Collective neonatal morbidity Group I n
Neonatal morbidity (No. of babies affected)
I
7
mitted to the intensive care nursery. This last subgroup included one fetus with microcephaly born to a mother with untreated phenylketonuria. Significantly different cesarean section rates were observed between the groups delivered after a normal final biophysical profile score (Table III). In each of these groups the majority of cesarean sections performed were for cephalopelvic disproportion and failure to progress. The patients in whom labor was induced despite an unfavorable cervix (group IV) constituted 19.2% (50 of 261) of those delivered following a normal biophysical profile scoring but accounted for 40.4% (21 of 52) of cesarean sections in that population. The cesarean section rate for patients with normal biophysical profile scoring managed according to protocol (groups I plus group II) was 14.7% (31 of 211) compared to 42% (21 of 50) for group IV (p < 0.005,X~). Among the cesarean sections in group IV, at least four were primary elective procedures on the combined basis of an unfavorable cervix, clinically large baby, and postdatism. During the period of this study the hospital's overall cesarean section rate was 16.5%. Comment
The appropriate management of the obstetric patient whose gestation has exceeded 42 completed weeks (postmaturity or postdates syndrome) remains one of the most difficult problems in modern perinatal medicine. The perinatal risks ofthe postdates syndrome are well established; perinatal mortality doubles for each additional week after the forty-second week." One simple solution to this problem would be to deliver all patients by the end of the forty-second week. However, such a nonselective approach, while being done to prevent perinatal morbidity and mortality, may create iatrogenic morbidity for the mother. In this present study, when this nonselective approach to timing of delivery was used, the cesarean section rate rose to 42%, more than 2.5 times the rate for the general population at our institution (16.5%). A more logical approach may be to consider both fetal and maternal prognostic factors in selecting the most appropriate management strategy. Fetal biophysical profile scoring, as measured in a study population of 12,620 high-risk patients, has proved to be a very accurate method of determination of fetal well-being
% 3.B
Group II n
I
Group III
%
n
3.2
6
I
Group IV
%
n
IB.7
2
I
% 4
at risk. 6 When this method was applied to this specialrisk category of postdate pregnancies, it appeared also to be of value in assigning fetal risk. In those fetuses with normal biophysical activities and normal amniotic fluid volume (n = 211), who were managed according to our protocol (Fig. 1), there were no perinatal deaths or fetal distress, low Apgar scores were infrequent (3.31 % and 1.89%, respectively), and subsequent neonatal morbidity was unusual (1.9%)(Table II). In contrast, in those fetuses exhibiting an abnormal biophysical profile score and/or oligohydramnios (n = 32), the incidence of fetal distress (22%), low Apgar scores (12.5%), and neonatal morbidity (19%) were all substantially and significantly increased (Table II). When considered collectively, neonatal morbidity ranged from 3.7% when the fetal biophysical profile score was normal to 18.7% when the score was abnormal (Table IV). These data indicate that fetal biophysical profile scoring facilitates differentiation of the normal noncom promised fetus from the compromised fetus within a population of postdates pregnancies. Accurate recognition of fetal risk, when in turn combined with maternal obstetric assessment (including cervical findings), allows for a rational and selective approach to patient care. The potential beneficial impact of such a selective approach in reducing maternal morbidity is clear. In this present study some of this benefit was realized. The cesarean section rates for patients with a normal fetus managed conservatively and those with a normal fetus delivered because of favorable cervical findings were similar (15% and 13%, respectively) and were not increased as compared to the population at large (16.5%). In contrast, both were sharply and significantly lower than the cesarean section rate observed in patients induced in a nonselective manner on the basis of gestational age alone (42%) (Table III). The results of this prospective clinical study of a selective management strategy for the postdates pregnancy are very encouraging. In study patients perinatal mortality was absent and morbidity was low while intervention rates were reduced, at least as compared to those observed among patients with nonselective intervention based on gestational age alone. Based on these findings we would suggest that it may no longer be reasonable to elect routine delivery of all patients at or beyond 42 completed weeks of gestation. In view of the
Biophysical scoring in postterm pregnancy
Volume 154 Number 2
proven reliability of fetal assessment methods and the potential risk of nondiscrimative intervention, selective patient care appears to be the method of choice. REFERENCES 1. Beischer NA, Brown JB, Smith MA, Townsend L. Studies in prolonged pregnancy I. The incidence of prolonged pregnancy. AMJ OBSTETGYNECOL 1969;103:476. 2. Hauth JC, Goodman MT, Gilstrap LC, Gilstrap JE. Postterm pregnancy, I. Obstet Gynecol 1980;56:467. 3. Devoe LD, Scholl JS. Post-dates pregnancy: assessment of fetal risk and obstetric management. J Reprod Med 1978;28:576. 4. Crowley P, O'Herlitty E, Boylan P. The value of ultrasound measurement of amniotic fluid volume in the management of prolonged pregnancies. Br J Obstet Gynaecol 1984; 91:444.
5. Manning FA, Morrison J, Lange JR, Harman CR. Antepartum determination of fetal health: composite fetal biophysical profile scoring. Clin Perinat 1982;9:285. 6. Manning FA, Morrison J, Lange JR, Harman CR, Chamberlain PF. Fetal assessment based upon fetal biophysical profile scoring: experience in 12,620 referred high-risk pregnancies I. Perinatal mortality by frequency and etiology. AM J OBSTET GYNECOL 1985; 151 :343. 7. Manning FA, Lange JR, Morrison I, Harman CR. Fetal biophysical profile score and the nonstress test: a comparative trial. Obstet Gynecol 1984;64:326. 8. Chamberlain PF, Manning FA, Morrison I, Harman CR, Lange JR. Ultrasound evaluation of amniotic fluid volume. I. The relationship of marginal and decreased amniotic fluid volumes to perinatal outcome. AM J OBSTET GYNECOL 1984;150:245. 9. Butler MR, Bonham DG, ed. British perinatology mortality study-first report. Edinburgh: Livingstone, 1963.
Occurrence of molar pregnancy in patients undergoing elective abortion: Comparison with other clinical presentations Basil Ho Yuen, M.B., and Patti Burch Callegari, R.N. Vancouver, British Columbia, Canada Clinical data of molar pregnancies found in women undergoing elective abortion (group 1, n = 39) were compared to those of molar pregnancies in women who experienced spontaneous abortions (group 2, n = 157) and women in whom molar pregnancy was discovered before symptoms of spontaneous abortion were evident (group 3, n = 209). Group 1 women were younger and experienced uterine evacuation at an earlier stage of amenorrhea than groups 2 and 3. Group 3 had larger uteri at evacuation and longer intervals of positive tests for the l3-subunit of human chorionic gonadotropin during the postmolar phase as compared with groups 1 and 2. On the basis of available provincial data for the number of elective abortions, the estimated incidence of molar pregnancies in this population was 1 : 2,699. The presence of malignant gestational trophoblastic neoplasia was documented in a single patient in group 1. The incidence of malignant gestational trophoblastic neoplasia in this group was not significantly different from that in groups 2 and 3. Routine pathologic examination of the products of conception in women undergoing elective abortion coupled with routine assays of the l3-subunit of human chorionic gonadotropin when molar pregnancy is found can identify both noninvasive and invasive trophoblastic disease in these women. (AM J OesTET GVNECOL 1986;154:273-6.)
Key words: Molar pregnancy, elective abortion, spontaneous abortion
Currently, there is little information about the frequency and clinical behavior of molar pregnancy found in women presenting for elective abortion. In this ar-
From the Gynaecologic Endocrine Laboratory, Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynaecology, Faculty of Medicine, University of British Columbia. Presented at the Forty-first Annual Meeting of The Society of Obstetricians and Gynaecologists of Canada, Jasper, Alberta, Canada, June 10-15, 1985. Reprint requests: Dr. B. Ho Yuen, Department of Obstetrics and Gynaecology, Grace Hospital, Room 2H30, 4490 Oak St., Vancouver, British Columbia V6H 3V5.
ticle we report on 39 patients with molar pregnancy discovered by routine pathologic examination of the products of conception from patients undergoing elective abortion in British Columbia between 1975 and 1984. The clinical course and regression patterns of the ~-subunit of human chorionic gonadotropin (l3-hCG) of these patients after molar pregnancy were contrasted to those in patients with molar pregnancies found by pathologic examination in women with spontaneous abortions and in women in whom molar pregnancies were discovered before symptoms and signs of spontaneous abortion occurred.
273
Volume 154 Number 2
The present study indicated a difference in overall survival between younger and older women, which can be explained simply on the basis of more younger women presenting with invasive disease in the earlier stages. The survival patterns are similar, stage by stage, for younger and older women. Different treatment modalities between younger women and older women with less advanced invasive disease in favor of surgery for younger women is an expression of the general trend to treat less advanced invasive disease, in this age group, with operation rather than radiation. However, when survival patterns are compared between younger and older women with Stage IB disease, survival patterns with radical hysterectomy treatment and radiation are similar for both age groups. Thus neither treatment modality favors younger women. It is our opinion, on the basis of the present review, that there has been a recent slight increase in the proportion of younger women diagnosed as having invasive cervical carcinoma. The susceptibility to a screening program, the natural history of the disease, and the response to treatment are similar for younger and older women.
REFERENCES I. Walton RJ, Allen HH, Anderson, GH, et al. Cervical cancer
screening programs. Can Med AssocJ 1982;127:581. 2. Bourne RG, Grove WD. Invasive carcinoma of the cervix in Queensland. MedJ Aust 1983;1:156. 3. Green GH. Cervical cancer and cytology screening in New Zealand. Br J Obstet Gynaecol 1978;85:818. 4. Berkeley AS, LiVolsi VA, Schwartz PE. Advanced squamous cell carcinoma of the cervix with recent normal Papanicoulaou tests. Lancet 1980;2:375. 5. Rylander E. Negative smears in women developing invasive cervical cancer. Acta Obstet Gynecol Scand 1977;56:115. 6. Prempree T, Patanaphan V, Sewchand W, et al. The influence of patients' age and tumor grade on the prognosis of carcinoma of the cervix. Cancer 1983;51: 1764. 7. Paterson MEL, Peel KR, Joslin CAF. Cervical smear histories of 500 women with invasive cervical cancer in Yorkshire. Br Med J 1984;289:896. 8. Carmichael JA, Jeffrey JF, Steele HD, et al. The cytologic history of 245 patients developing invasive cervical carcinoma. AM J OBSTET GVNECOL 1984; 148:685. 9. Walton RJ, Blanchet M, Boyes DA, et al. Cervical cancer screening programs (Department of National Health and Welfare Task Force Report). Can Med Assoc J 1976;114:1003.
Biophysical profile scoring in the management of the postterm pregnancy: An analysis of 307 patients J. M. Johnson, M.D., C. R. Harman, M.D., I. R. Lange, M.D., and F. A. Manning, M.D. Winnipeg, Manitoba, Canada Management and outcome were reviewed in 307 consecutive postterm pregnancies assessed by biophysical profile scoring. Twice-weekly scores accurately differentiated normal fetuses from those at risk for intrauterine hypoxia. When the profile score is normal, waiting for spontaneous labor results in healthy neonates and a much lower cesarean section rate (15% versus 42% for "prophylactic" induction). Confident conservative management of postterm pregnancy is possible. (AM J OSSTET GVNECOL 1986;154:269-73.)
Key words: Postterm pregnancy, biophysical profile scoring Pregnancy persisting beyond 42 weeks of gestation or 294 days from the first day of the last normal menFrom the Division of Maternal-Fetal Medicine, Department of Obstetrics, G.vnecology, and Reproductive Sciences, University of Manitoba. Presented at the Forty-first Annual Meeting of The Society of Obstetricians and G.vnaecologists of Canada, Jasper, Alberta, Canada, June 10-15, 1985. Reprinl reque.5t.5: Dr. C. R. Harman, Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, Women's HO.5pital, 735 Notre Dame Ave., WinniPeg, Manitoba, Canada R3E OL8.
strual period is considered postterm and occurs in approximately 10% of all pregnancies.' Postterm pregnancy is associated with an increase in perinatal mortality, meconium-stained liquor, fetal distress in labor, and subsequent development and behavioral disturbances." Although it is a common problem, there is no unanimity of opinion regarding optimal management. Previous studies have reached little agreement as to when fetal jeopardy begins, how accurately the most endangered fetuses can be detected, or whether safe limits
269
270 Johnson et al.
February, 1986 Am J Obstet Gynecol
B.P.S.
Normal Score
~
Abnormal Score
Pelvic Assessment
~
Unfavourable
Favourable
for A.R.M.
I
(I) Repeat B.P.S.
1/2 Week
I
(II) Labour
Induced
(UI) Delivery by
Appropriate Route
Fig. 1. Management protocol and outcome groups:(I). Normal biophysical profile scoring (B.P.S.), spontaneous labor (A.R.M., artificial rupture of membranes): (I I), Normal biophysical profile scoring, labor induced: (III), Abnormal biophysical profile scoring, delivery by appropriate route.
can be established for the continuation of prolonged gestation.'-' Because of this uncertainty, many centers continue to follow a policy of uniform delivery when 42 weeks of gestation is reached. The potentially serious complications of postmaturity in some (10% to 20%) is seen as justification for the possibly unnecessary intervention in the remaining 80% to 90% of pregnancies. At our institution, antepartum fetal risk determination is based on a composite fetal biophvsical profile score.-··" The purpose of this study was to evaluate the benefits, if any, that are achieved when fetal biophysical profile scoring was used in the management of the patient with a postdate pregnancy. Two specific questions were addressed: (1) Can this method of assessment accurately detect the fetus at risk of intrauterine compromise because of postmaturity? (2) If the fetus continues to appear healthy according to the biophysical profile scoring, does withholding intervention beyond 42 weeks result in improved maternal outcome? If this practicable means of fetal assessment can accomplish both accurate intervention when the fetus is jeopardized and confident conservatism that protects the mother from the consequences of unnecessary intervention when the fetus is healthy, then its application in prolonged gestation would be validated. Material and methods
Criteria for inclusion in this prospective management study were as follows: single pregnancies with no
other complications, with firmly established gestational length of more than 294 days from the known last normal menstrual period. Dates were confirmed in all patients by early examination or early ultrasound studies or by both, and patients were excluded if the ultrasound findings on referral to the study group resulted in reassignment of dates. Biophysical profile scoring as described by Manning et al." was performed twice weekly on all patients. If all four ultrasound parameters (fetal movement, muscle tone, fetal breathing movements and amniotic fluid volume) were present, the biophysical profile scoring was considered to be normal, and a nonstress test was not done (biophysical profile scoring of 8/8'). If anyone of the first three ultrasound parameters listed was not present, a nonstress test was given, and if reactive, the biophysical profile scoring was again considered normal (biophysical profile scoring of 811 0). For scores of 6110 or 8110 in which amniotic fluid volume was the abnormal variable (pocket of <2.0 cm in vertical dimension, measured in two planes), the score was considered abnormal. Based on the biophysical profile score obtained at each visit, the patient was managed according to the protocol illustrated in Fig. 1. Three outcome groups were generated by the study (Table I). Group I consisted of patients with normal biophvsical profile scoring, followed without intervention until the spontaneous onset of labor. Group II patients also had normal scores until labor, which was induced with a cervix favorable for artificial rupture of membranes. Group III consisted of those in whom an abnormal score suggesting fetal compromise constituted a definite indication for delivery, which was undertaken within 24 hours by the appropriate route. For the purposes of analysis, group III was subdivided according to the depth of the largest amniotic fluid pocket available .' A fourth group of patients was generated because the attending physicians did not always follow the recommendations of the protocol. These patients all had a normal score at their last assessment but labor was induced "for dates only" despite a cervix unfavorable for artificial rupture of the membranes (Group IV). In all cases the last biophysical profile scoring before delivery was the score of preference in the analysis. Parameters of fetal perinatal morbidity were defined as (I) fetal distress in labor requiring emergency cesarean section, (2) 5-minute Apgar score of",,6, and (3) meconium aspiration requiring admission to neonatal intensive care. Apgar scores were assigned by independent observers. Intubation and suctioning were performed by a neonatologist or anesthetist on all infants with meconium present in amniotic fluid. The rate of cesarean section was calculated for each group.
Biophysical scoring in postterm pregnancy 271
Volume 154 Number 2
Table I. Management/outcome groups (n = 293) Mean birth weight Group
Biophysical profile scoring
I II III IV
Normal Normal Abnormal Normal
Description of delivery
Spontaneous labor Induced labor/favorable cervix Delivered because of fetal indications Induced for dates only
180 31 32 50
(gm)
Mean gestational length (days)
3997 3853 3664 3799
301 302 298 301
Table II. Incidence of perinatal morbidity Group I Morbidity
n
Cesarean section for fetal distress 5 min Apgar score of ",;:6 Meconium aspiration to intensive care nursery
6 3 4
I
Group II
%
n
3.3 1.6
2.2
I
% 3.2 3.2
o
Group III n
7 4 6
1
Group IV
%
n
22* 12.5* 19*
7
I
% 14t 2
I
o
*Significantly different from all other groups, p < 0.05 by X'. tSignificantly different from groups I and II, p < 0.05 by X'.
The four management/outcome groups were compared with use of X' contingency tables or Student's t test as was appropriate. A value of p < 0.05 was considered significant.
Results Over the 3-year period beginning September 1, 1981, 307 women referred for composite fetal assessment met the entry criteria. Fourteen of these women were delivered because of changes in maternal condition not related to postdatism and were excluded from further analysis. This resulted in a final study population of 293 patients, who had a total of 503 assessments. These patients were distributed among the four outcome/management groups, as shown in Table I. While differing in number, these groups did not differ significantly in distribution of maternal age, parity, or birth weight. Although patients in group III tended to require delivery sooner (for abnormal biophysical profile scoring that suggested fetal compromise) the range of time beyond 42 weeks at which the scoring became abnormal (0 to 12 days) rendered this difference statistically nonsignificant (Student's t test). All fetuses in group III were delivered within 24 hours of their abnormal biophysical profile scoring, whereas the majority of all other groups delivered within 4 days of their normal, last profile scoring. There were no stillbirths or perinatal deaths in the entire study population. There were significant differences in perinatal morbidity between groups (Table II). Fetuses in group III required cesarean section for fetal distress more often than any other group and had a total cesarean section rate of 37.5%. Fetuses in group III (delivered for abnormal biophysical profile scoring) accounted for 44% of low 5-minute Apgar scores and for 60% of neonatal admission to intensive care for
Table III. Cesarean section following normal biophysical profile scoring Group
Cesarean section for fetal distress
I
%
n
6 I
3.3 3.2
27 4
15 13
7
14*
21
42*
n
I. Spontaneous labor II. Induced labor favorable cervix IV. Induced for dates only
Total cesarean sections
t
%
*Significantly different from groups I and II, p < 0.01 by X'·
meconium aspiration. The frequency of cesarean delivery for fetal distress was also increased in group IV, but the frequency of low Apgar scores and serious meconium aspiration were not. Within group III (32 patients) perinatal morbidity was highest in fetuses with the lowest amniotic fluid volume. Among the 11 with overt oligohydramnios (largest pocket of fluid < 1.0 cm) four required cesarean section for fetal distress, eight had meconium in amniotic fluid, and six had meconium below their vocal cords, necessitating admission to the intensive care nursery for three of them. Six of the 11 had low Apgar scores at 1 minute and two at 5 minutes after birth. The nine fetuses with marginal fluid (pocket of 1 to 2 cm) had an average amniotic fluid volume of 1.6 cm. In this subgroup, two required delivery by cesarean section (there were no low 5-minute Apgar scores), and one was admitted to the intensive care nursery for meconium aspiration. In the subgroup with normal (>2.0 cm) amniotic fluid volume but abnormal biophysical profile scoring, six of 12 required cesarean section, two had low Apgar scores at 5 minutes, and two were ad-
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February, 1986 Am J Obstet Gynecol
Table IV. Collective neonatal morbidity Group I n
Neonatal morbidity (No. of babies affected)
I
7
mitted to the intensive care nursery. This last subgroup included one fetus with microcephaly born to a mother with untreated phenylketonuria. Significantly different cesarean section rates were observed between the groups delivered after a normal final biophysical profile score (Table III). In each of these groups the majority of cesarean sections performed were for cephalopelvic disproportion and failure to progress. The patients in whom labor was induced despite an unfavorable cervix (group IV) constituted 19.2% (50 of 261) of those delivered following a normal biophysical profile scoring but accounted for 40.4% (21 of 52) of cesarean sections in that population. The cesarean section rate for patients with normal biophysical profile scoring managed according to protocol (groups I plus group II) was 14.7% (31 of 211) compared to 42% (21 of 50) for group IV (p < 0.005,X~). Among the cesarean sections in group IV, at least four were primary elective procedures on the combined basis of an unfavorable cervix, clinically large baby, and postdatism. During the period of this study the hospital's overall cesarean section rate was 16.5%. Comment
The appropriate management of the obstetric patient whose gestation has exceeded 42 completed weeks (postmaturity or postdates syndrome) remains one of the most difficult problems in modern perinatal medicine. The perinatal risks ofthe postdates syndrome are well established; perinatal mortality doubles for each additional week after the forty-second week." One simple solution to this problem would be to deliver all patients by the end of the forty-second week. However, such a nonselective approach, while being done to prevent perinatal morbidity and mortality, may create iatrogenic morbidity for the mother. In this present study, when this nonselective approach to timing of delivery was used, the cesarean section rate rose to 42%, more than 2.5 times the rate for the general population at our institution (16.5%). A more logical approach may be to consider both fetal and maternal prognostic factors in selecting the most appropriate management strategy. Fetal biophysical profile scoring, as measured in a study population of 12,620 high-risk patients, has proved to be a very accurate method of determination of fetal well-being
% 3.B
Group II n
I
Group III
%
n
3.2
6
I
Group IV
%
n
IB.7
2
I
% 4
at risk. 6 When this method was applied to this specialrisk category of postdate pregnancies, it appeared also to be of value in assigning fetal risk. In those fetuses with normal biophysical activities and normal amniotic fluid volume (n = 211), who were managed according to our protocol (Fig. 1), there were no perinatal deaths or fetal distress, low Apgar scores were infrequent (3.31 % and 1.89%, respectively), and subsequent neonatal morbidity was unusual (1.9%)(Table II). In contrast, in those fetuses exhibiting an abnormal biophysical profile score and/or oligohydramnios (n = 32), the incidence of fetal distress (22%), low Apgar scores (12.5%), and neonatal morbidity (19%) were all substantially and significantly increased (Table II). When considered collectively, neonatal morbidity ranged from 3.7% when the fetal biophysical profile score was normal to 18.7% when the score was abnormal (Table IV). These data indicate that fetal biophysical profile scoring facilitates differentiation of the normal noncom promised fetus from the compromised fetus within a population of postdates pregnancies. Accurate recognition of fetal risk, when in turn combined with maternal obstetric assessment (including cervical findings), allows for a rational and selective approach to patient care. The potential beneficial impact of such a selective approach in reducing maternal morbidity is clear. In this present study some of this benefit was realized. The cesarean section rates for patients with a normal fetus managed conservatively and those with a normal fetus delivered because of favorable cervical findings were similar (15% and 13%, respectively) and were not increased as compared to the population at large (16.5%). In contrast, both were sharply and significantly lower than the cesarean section rate observed in patients induced in a nonselective manner on the basis of gestational age alone (42%) (Table III). The results of this prospective clinical study of a selective management strategy for the postdates pregnancy are very encouraging. In study patients perinatal mortality was absent and morbidity was low while intervention rates were reduced, at least as compared to those observed among patients with nonselective intervention based on gestational age alone. Based on these findings we would suggest that it may no longer be reasonable to elect routine delivery of all patients at or beyond 42 completed weeks of gestation. In view of the
Biophysical scoring in postterm pregnancy
Volume 154 Number 2
proven reliability of fetal assessment methods and the potential risk of nondiscrimative intervention, selective patient care appears to be the method of choice. REFERENCES 1. Beischer NA, Brown JB, Smith MA, Townsend L. Studies in prolonged pregnancy I. The incidence of prolonged pregnancy. AMJ OBSTETGYNECOL 1969;103:476. 2. Hauth JC, Goodman MT, Gilstrap LC, Gilstrap JE. Postterm pregnancy, I. Obstet Gynecol 1980;56:467. 3. Devoe LD, Scholl JS. Post-dates pregnancy: assessment of fetal risk and obstetric management. J Reprod Med 1978;28:576. 4. Crowley P, O'Herlitty E, Boylan P. The value of ultrasound measurement of amniotic fluid volume in the management of prolonged pregnancies. Br J Obstet Gynaecol 1984; 91:444.
5. Manning FA, Morrison J, Lange JR, Harman CR. Antepartum determination of fetal health: composite fetal biophysical profile scoring. Clin Perinat 1982;9:285. 6. Manning FA, Morrison J, Lange JR, Harman CR, Chamberlain PF. Fetal assessment based upon fetal biophysical profile scoring: experience in 12,620 referred high-risk pregnancies I. Perinatal mortality by frequency and etiology. AM J OBSTET GYNECOL 1985; 151 :343. 7. Manning FA, Lange JR, Morrison I, Harman CR. Fetal biophysical profile score and the nonstress test: a comparative trial. Obstet Gynecol 1984;64:326. 8. Chamberlain PF, Manning FA, Morrison I, Harman CR, Lange JR. Ultrasound evaluation of amniotic fluid volume. I. The relationship of marginal and decreased amniotic fluid volumes to perinatal outcome. AM J OBSTET GYNECOL 1984;150:245. 9. Butler MR, Bonham DG, ed. British perinatology mortality study-first report. Edinburgh: Livingstone, 1963.
Occurrence of molar pregnancy in patients undergoing elective abortion: Comparison with other clinical presentations Basil Ho Yuen, M.B., and Patti Burch Callegari, R.N. Vancouver, British Columbia, Canada Clinical data of molar pregnancies found in women undergoing elective abortion (group 1, n = 39) were compared to those of molar pregnancies in women who experienced spontaneous abortions (group 2, n = 157) and women in whom molar pregnancy was discovered before symptoms of spontaneous abortion were evident (group 3, n = 209). Group 1 women were younger and experienced uterine evacuation at an earlier stage of amenorrhea than groups 2 and 3. Group 3 had larger uteri at evacuation and longer intervals of positive tests for the l3-subunit of human chorionic gonadotropin during the postmolar phase as compared with groups 1 and 2. On the basis of available provincial data for the number of elective abortions, the estimated incidence of molar pregnancies in this population was 1 : 2,699. The presence of malignant gestational trophoblastic neoplasia was documented in a single patient in group 1. The incidence of malignant gestational trophoblastic neoplasia in this group was not significantly different from that in groups 2 and 3. Routine pathologic examination of the products of conception in women undergoing elective abortion coupled with routine assays of the l3-subunit of human chorionic gonadotropin when molar pregnancy is found can identify both noninvasive and invasive trophoblastic disease in these women. (AM J OesTET GVNECOL 1986;154:273-6.)
Key words: Molar pregnancy, elective abortion, spontaneous abortion
Currently, there is little information about the frequency and clinical behavior of molar pregnancy found in women presenting for elective abortion. In this ar-
From the Gynaecologic Endocrine Laboratory, Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynaecology, Faculty of Medicine, University of British Columbia. Presented at the Forty-first Annual Meeting of The Society of Obstetricians and Gynaecologists of Canada, Jasper, Alberta, Canada, June 10-15, 1985. Reprint requests: Dr. B. Ho Yuen, Department of Obstetrics and Gynaecology, Grace Hospital, Room 2H30, 4490 Oak St., Vancouver, British Columbia V6H 3V5.
ticle we report on 39 patients with molar pregnancy discovered by routine pathologic examination of the products of conception from patients undergoing elective abortion in British Columbia between 1975 and 1984. The clinical course and regression patterns of the ~-subunit of human chorionic gonadotropin (l3-hCG) of these patients after molar pregnancy were contrasted to those in patients with molar pregnancies found by pathologic examination in women with spontaneous abortions and in women in whom molar pregnancies were discovered before symptoms and signs of spontaneous abortion occurred.
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