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Time lag for development of acidosis
and irritability caused 4 of the 10 subjects to withdraw from the study, and were reported to some degree by all the subjects. New Way to Evaluate NSTs Arias J, Saldana L, Rivera-Alsina M, Ali V. Fetal heart rate acceleration: fetal movement ratio in the man-
agement of high-risk pregnancy. Obstet Gynecol 60:427, 1982. This report documents a simple and reliable method for interpreting the nonstress test (NST). The authors used a ratio obtained by dividing the total number of FHR accelerations associated with fetal movements by the total number of fetal movements. Each NST lasted 40-50 min. Fetuses at risk who were delivered within 7 days of the last NST form the basis for this report. A total of 318 women underwent antenatal FHR testing, many of them serially. Of these high risk women, only 15% had abnormal acceleration:fetal movement ratios within 7 days of delivery (47 patients). In 55% of these patients the fetus showed evidence of intrapartum distress. Conversely, only 2% of patients with normal NST’s exhibited signs of fetal distress (P = 0.001). A significantly higher incidence of small-for-gestational age infants was found when high-risk women had an acceleration:fetal movement ratio of less than 10%. However, the authors state that “a single initial acceleration:fetal movement ratio below 10% should not be considered a mandate for action before term, as the ratio is likely to rise with advancing gestational age.” It is suggested that a persistently nonreactive NST (ratio less than 10%) be viewed with concern and delivery considered. In comparison to the more widely accepted methods of evaluating the NST with follow-up by oxytocin challenge test, the authors have found their method to be more reliable, selecting 52.4% of the compromised fetuses compared with 34.5% using traditional methods. Estrogen and Risk of Endometrial Cancer Ziel H. Estrogen’s role in endometrial cancer. Obstet Gynecol 60:509, 1982. In this review article Dr. Ziel reports the data from 15 retrospective case-control studies that have correlated unopposed Journal of Nurse-Midwifery
??
estrogen use with the likelihood of subsequent development of endometrial cancer. He cites the groups of women most at risk, focusing mainly on those women who either used sequential oral contraceptives or received estrogen replacement therapy, and concludes that “the falling incidence of endometrial cancer associated with diminished estrogen sales is the final proof.” Outpatient Breast Biopsy Mitchell G, Homer M. Outpatient breast biopsies on a gynecologic service. Am J Obstet Gynecol 144:127, 1982. This report documents the safety and advantages of outpatient performance of breast biopsies using local anesthesia. The authors report 146 breast biopsies done in 143 women over a five-year period. Complications were uncommon and readily diagnosed and managed, the most frequent was mild ecchymosis of the skin which cleared quickly (71 cases). Other complications included acute bleeding requiring resuturing (5 cases); hematoma, not requiring evacuation (7 cases); infection (1 case); and accidental incision ( 1 case). Patient acceptance was uniformly good, and the authors recommend that this procedure become a part of the obstetrician-gynecologist’s armamentarium. Time Lag for Development of Acidosis
Fleischer A, Schulman H, Jagani N, et al. The development of fetal acidosis in the presence of an abnormal fetal heart rate tracing. I. The average for gestational age fetus. Am J Obstet Gynecol 144z55, 1982. In an attempt to further refine the use of FHR tracings to predict the seriously compromised infant, these authors have examined the relationship between the duration in time of an abnormal FHR pattern and the delivery of an acidotic infant. This study defines the time lag between the onset of abnormal FHR and a fall in pH in a group of initially healthy, term, and appropriate-for-gestational age infants. As the development of acidosis and ultimate perinatal outcome depend on three factors (initial status, duration of
Vol. 28, No. 2, March/April
1983
stress, and intensity of stress), the research focused on the types of abnormal FHR patterns and their duration in time, while maintaining initial status as a constant. In this series 16% of the patients showed acidosis at the time of onset of abnormal FHR and were not included in the research protocol. The remaining cases showed a remarkably low incidence of acidosis during the first 120 min of abnormal FHR recording. On the basis of this study it may be speculated that in the majority (approximately 85%) of situations in which the fetus is exposed to hypoxic stresses, the levels are mild enough for its intrinsic compensatory mechanisms to maintain acid-base homeostasis for 90 - 100 min. Following this time period, rapid cumulative acidosis was seen, varying according to the FHR pattern observed. The time interval required to produce acidosis was significantly lower in the group with late decelerations (115 min) than in those with variable decelerations (145 min) or those with no decelerations but with a flat-line tracing (185 min).
Running and Amenorrhea
Sanborn C, Martin B, Wagner W. Is athletic amenorrhea specific to runners? Am J Obstet Gynecol 143:859, 1982. In this study, swimmers and cyclists were compared to runners in order to determine whether amenorrhea was a common characteristic of endurance training or was unique to runners. Questionnaires were received from 237 runners, 197 swimmers, and 33 cycliits. The prevalence of amenorrhea was higher than expected for all three groups as compared to nonathletes, but was dramatically higher for the runners (25.7% u 12% for swimmers and for cyclists). The frequency of amenorrhea in swimmers and cyclists remained constant regardless of the number of miles trained per week. Among runners, however, a positive correlation (P < 0.001) was found between the frequency of amenorrhea and the number of miles run per week. Among the runners, the prevalence of amenorrhea was higher and increased more rapidly with longer training in women in the lightest weight categoy. As percentage of body fat decreased, the incidence of amenorrhea increased.
41
agement of high-risk pregnancy. Obstet Gynecol 60:427, 1982. This report documents a simple and reliable method for interpreting the nonstress test (NST). The authors used a ratio obtained by dividing the total number of FHR accelerations associated with fetal movements by the total number of fetal movements. Each NST lasted 40-50 min. Fetuses at risk who were delivered within 7 days of the last NST form the basis for this report. A total of 318 women underwent antenatal FHR testing, many of them serially. Of these high risk women, only 15% had abnormal acceleration:fetal movement ratios within 7 days of delivery (47 patients). In 55% of these patients the fetus showed evidence of intrapartum distress. Conversely, only 2% of patients with normal NST’s exhibited signs of fetal distress (P = 0.001). A significantly higher incidence of small-for-gestational age infants was found when high-risk women had an acceleration:fetal movement ratio of less than 10%. However, the authors state that “a single initial acceleration:fetal movement ratio below 10% should not be considered a mandate for action before term, as the ratio is likely to rise with advancing gestational age.” It is suggested that a persistently nonreactive NST (ratio less than 10%) be viewed with concern and delivery considered. In comparison to the more widely accepted methods of evaluating the NST with follow-up by oxytocin challenge test, the authors have found their method to be more reliable, selecting 52.4% of the compromised fetuses compared with 34.5% using traditional methods. Estrogen and Risk of Endometrial Cancer Ziel H. Estrogen’s role in endometrial cancer. Obstet Gynecol 60:509, 1982. In this review article Dr. Ziel reports the data from 15 retrospective case-control studies that have correlated unopposed Journal of Nurse-Midwifery
??
estrogen use with the likelihood of subsequent development of endometrial cancer. He cites the groups of women most at risk, focusing mainly on those women who either used sequential oral contraceptives or received estrogen replacement therapy, and concludes that “the falling incidence of endometrial cancer associated with diminished estrogen sales is the final proof.” Outpatient Breast Biopsy Mitchell G, Homer M. Outpatient breast biopsies on a gynecologic service. Am J Obstet Gynecol 144:127, 1982. This report documents the safety and advantages of outpatient performance of breast biopsies using local anesthesia. The authors report 146 breast biopsies done in 143 women over a five-year period. Complications were uncommon and readily diagnosed and managed, the most frequent was mild ecchymosis of the skin which cleared quickly (71 cases). Other complications included acute bleeding requiring resuturing (5 cases); hematoma, not requiring evacuation (7 cases); infection (1 case); and accidental incision ( 1 case). Patient acceptance was uniformly good, and the authors recommend that this procedure become a part of the obstetrician-gynecologist’s armamentarium. Time Lag for Development of Acidosis
Fleischer A, Schulman H, Jagani N, et al. The development of fetal acidosis in the presence of an abnormal fetal heart rate tracing. I. The average for gestational age fetus. Am J Obstet Gynecol 144z55, 1982. In an attempt to further refine the use of FHR tracings to predict the seriously compromised infant, these authors have examined the relationship between the duration in time of an abnormal FHR pattern and the delivery of an acidotic infant. This study defines the time lag between the onset of abnormal FHR and a fall in pH in a group of initially healthy, term, and appropriate-for-gestational age infants. As the development of acidosis and ultimate perinatal outcome depend on three factors (initial status, duration of
Vol. 28, No. 2, March/April
1983
stress, and intensity of stress), the research focused on the types of abnormal FHR patterns and their duration in time, while maintaining initial status as a constant. In this series 16% of the patients showed acidosis at the time of onset of abnormal FHR and were not included in the research protocol. The remaining cases showed a remarkably low incidence of acidosis during the first 120 min of abnormal FHR recording. On the basis of this study it may be speculated that in the majority (approximately 85%) of situations in which the fetus is exposed to hypoxic stresses, the levels are mild enough for its intrinsic compensatory mechanisms to maintain acid-base homeostasis for 90 - 100 min. Following this time period, rapid cumulative acidosis was seen, varying according to the FHR pattern observed. The time interval required to produce acidosis was significantly lower in the group with late decelerations (115 min) than in those with variable decelerations (145 min) or those with no decelerations but with a flat-line tracing (185 min).
Running and Amenorrhea
Sanborn C, Martin B, Wagner W. Is athletic amenorrhea specific to runners? Am J Obstet Gynecol 143:859, 1982. In this study, swimmers and cyclists were compared to runners in order to determine whether amenorrhea was a common characteristic of endurance training or was unique to runners. Questionnaires were received from 237 runners, 197 swimmers, and 33 cycliits. The prevalence of amenorrhea was higher than expected for all three groups as compared to nonathletes, but was dramatically higher for the runners (25.7% u 12% for swimmers and for cyclists). The frequency of amenorrhea in swimmers and cyclists remained constant regardless of the number of miles trained per week. Among runners, however, a positive correlation (P < 0.001) was found between the frequency of amenorrhea and the number of miles run per week. Among the runners, the prevalence of amenorrhea was higher and increased more rapidly with longer training in women in the lightest weight categoy. As percentage of body fat decreased, the incidence of amenorrhea increased.
41