Richard H. Paul

Low-Dose Aspirin to Prevent Preeclampsia in Women at High Risk

Background Whether low-dose aspirin prevents preeclampsia is unclear. It is not recommended as prophylaxis in women at low risk for preeclampsia but may reduce the incidence of the disease in women at high risk. Methods We conducted a double-blind, randomized, placebo-controlled trial in four groups of pregnant women at high risk for preeclampsia, including 471 women with pregestational insulin-treated diabetes mellitus, 774 women with chronic hypertension, 688 women with multifetal gestations, and 606 women who had had preeclampsia during a previous pregnancy. The women were enrolled between gestational weeks 13 and 26 and received either 60 mg of aspirin or placebo daily. Results Outcome data were obtained on all but 36 of the 2539 women who entered the study. The incidence of preeclampsia was similar in the 1254 women in the aspirin group and the 1249 women in the placebo group (aspirin, 18 percent; placebo, 20 percent; P = 0.23). The incidences in the aspirin and placebo groups for each of the four hi...

Risk factors for preeclampsia, abruptio placentae, and adverse neonatal outcomes among women with chronic hypertension

Background Women with chronic hypertension who become pregnant have an increased risk of preeclampsia and adverse neonatal outcomes. However, within this group, the risk factors for these adverse events are not known. Methods We analyzed data on outcomes for 763 women with chronic hypertension enrolled in a multicenter trial of low-dose aspirin for the prevention of preeclampsia. Preeclampsia was defined as new-onset proteinuria (urinary protein excretion, ≥300 mg per 24 hours) in the 682 women without proteinuria at base line. It was defined according to strict clinical criteria in the 81 women who had proteinuria at base line. The end points were maternal and neonatal outcomes. Results Among the 763 women, 193 (25 percent) had preeclampsia. The frequency of preeclampsia was not affected by the presence of proteinuria at base line (27 percent among women with proteinuria, vs. 25 percent among those without it), but it was greater in women who had had hypertension for at least four years (31 percent vs. 2...

Uterine rupture after previous cesarean delivery: maternal and fetal consequences.

OBJECTIVE The purpose of this study was to identify the risk factors associated with overt, catastrophic uterine rupture and to report maternal and neonatal outcomes. The associated elapsed time window for delivery of an uncompromised neonate was also investigated. STUDY DESIGN A retrospective study with review of charts and monitor strips was performed. RESULTS Between Jan. 1, 1983, and June 30, 1992, there were 106 cases of uterine rupture at our institution. Of these, seven charts were incomplete and excluded; of the remainder, 28 patients had complete, 13 patients had partial, and 58 patients had no fetal extrusion into the maternal abdomen. Maternal characteristics or intrapartum events were not predictive of the catastrophic extent of uterine rupture. There was one maternal death. Complete fetal extrusion was associated with a higher incidence of perinatal mortality and morbidity. Significant neonatal morbidity occurred when > or = 18 minutes elapsed between the onset of prolonged deceleration and delivery. CONCLUSION Neonatal and maternal complications in uterine rupture with complete fetal extrusion were low with prompt intervention.

A comparison of misoprostol and prostaglandin E2 gel for preinduction cervical ripening and labor induction

OBJECTIVE Our purpose was to compare the safety and efficacy of intravaginal misoprostol versus intracervical prostaglandin E2 (dinoprostone) gel for preinduction cervical ripening and induction of labor. STUDY DESIGN One hundred thirty-five patients with indications for induction of labor and unfavorable cervices were randomly assigned to receive either intravaginal misoprostol or intracervical dinoprostone. Fifty microgram tablets of misoprostol were placed in the posterior vaginal fornix every 3 hours for a maximum of six doses. Prostaglandin E2 in gel form, 0.5 mg, was placed into the endocervix every 6 hours for a maximum of three doses. Medication was not given after either spontaneous rupture of membranes or beginning of active labor. RESULTS Among 135 patients enrolled, 68 received misoprostol and 67 received dinoprostone. The average interval from start of induction to vaginal delivery was shorter in the misoprostol group (903.3 +/- 482.1 minutes) than in the dinoprostone group (1410.9 +/- 869.1 minutes) (p < 0.001). Oxytocin augmentation of labor occurred more often in the dinoprostone group (65.7%) than in the misoprostol group (33.8%) (p < 0.001). There were no significant differences between routes of delivery. Ten of the misoprostol-treated patients (14.7%) and 13 of the dinoprostone-treated patients (19.4%) had cesarean deliveries. There was a higher prevalence of tachysystole (six or more uterine contractions in a 10-minute window for two consecutive 10-minute periods) in the misoprostol group (36.7%) than in the dinoprostone group (11.9%) (p < 0.001). However, there were no significant differences in frequency of uterine hyperstimulation or hypertonus. There was a higher prevalence of meconium passage in the misoprostol group (27.9%) than in the dinoprostone group (10.5%) (p < 0.05). There was no significant difference in frequency of abnormal fetal heart rate tracings, 1- or 5-minute Apgar scores < 7, neonatal resuscitations, or admissions to the neonatal intensive care unit between the two groups. CONCLUSIONS Vaginally administered misoprostol is an effective agent for cervical ripening and induction of labor; however when given at this dosage, it is associated with a higher prevalence of tachysystole and meconium passage than is dinoprostone. Further studies to compare the safety of misoprostol to that of dinoprostone and to delineate an optimal dosing regimen for misoprostol are needed.

Disruption of Prior Uterine Incision following Misoprostol for Labor Induction in Women with Previous Cesarean Delivery

Background Although induction of labor in women with prior cesareans is controversial, we compared misoprostol to oxytocin in such women in a randomized trial. The investigation was terminated prematurely because of safety concerns. Cases Disruption of the prior uterine incision was found in two of 17 misoprostol-treated women. The first woman underwent repeat cesarean delivery at 42 weeks because of fetal tachycardia and repetitive late decelerations. A 10-cm vertical rent in the anterior myometrium was discovered. The second woman underwent induction for fetal growth restriction. Loss of fetal heart tones and abnormal abdominal contour prompted emergent cesarean for suspected uterine rupture. An 8-cm longitudinal uterine defect was found. Conclusion When misoprostol is used in women with previous cesareans, there is a high frequency of disruption of prior uterine incisions.

Asthma during pregnancy

OBJECTIVE: To determine neonatal and maternal outcomes stratified by asthma severity during pregnancy by using the 1993 National Asthma Education Program Working Group on Asthma and Pregnancy definitions of asthma severity. The primary hypothesis was that moderate or severe asthmatics would have an increased incidence of delivery at <32 weeks of gestation compared with nonasthmatic controls. METHODS: This was a multicenter, prospective, observational cohort study conducted over 4 years at 16 university hospital centers. Asthma severity was defined according to the National Asthma Education Program Working Group on Asthma and Pregnancy classification and modified to include medication requirements. This study had 80% power to detect a 2- to 3-fold increase in delivery less than 32 weeks of gestation among the cohort with the moderate or severe asthma compared with controls. Secondary outcome measures included obstetrical and neonatal outcomes. RESULTS: The final analysis included 881 nonasthmatic controls, 873 with mild asthma, 814 with moderate, and 52 with severe asthma. There were no significant differences in the rates of preterm delivery less than 32 weeks (moderate or severe 3.0%, mild 3.4%, controls 3.3%; P = .873) or less than 37 weeks of gestation. There were no significant differences for neonatal outcomes except discharge diagnosis of neonatal sepsis among the mild group compared with controls, adjusted odds ratio 2.9, 95% confidence interval 1.2, 6.8. There were no significant differences for maternal complications except for an increase in overall cesarean delivery rate among the moderate-or-severe group compared with controls (adjusted odds ratio 1.4, 95% confidence interval 1.1, 1.8). CONCLUSION: Asthma was not associated with a significant increase in preterm delivery or other adverse perinatal outcomes other than a discharge diagnosis of neonatal sepsis. Cesarean delivery rate was increased among the cohort with moderate or severe asthma. LEVEL OF EVIDENCE: II-2

Emergency peripartum hysterectomy and associated risk factors

OBJECTIVE Peripartum hysterectomy at Los Angeles County-University of Southern California Medical Center was reviewed and associated risk factors were identified. STUDY DESIGN Retrospective descriptive and cohort analysis from January 1985 to June 1990 was carried out. Adjusted relative risks for hysterectomy with 95% confidence intervals for identified risk factors were calculated where possible. RESULTS There were 123 cases of emergency peripartum hysterectomy (incidence of 1.3/1000 births). Indications for hysterectomy were primarily placenta accreta (n = 61), uterine atony (n = 25), unspecified uterine bleeding (n = 19), and uterine rupture (n = 14). The relative risk of emergency hysterectomy was 95.5 (95% confidence interval 66.7 to 136.9) for cesarean delivery, 10.78 (95% confidence interval 7.56 to 15.37) for prior cesarean delivery, and 97.29 (95% confidence interval 70.28 to 134.70) for placenta previa. CONCLUSIONS Cesarean delivery, prior cesarean delivery, placenta previa, placenta accreta, and uterine atony were identified risk factors for emergency peripartum hysterectomy.

Antepartum fetal heart rate testing: I. Evolution of the nonstress test

On May 1, 1975, at Womens Hospital, Los Angeles County--University of Southern California Medical Center, a new antepartum fetal heart rate (AFHRT) protocol was put into clinical use. This included the widely used contraction stress test (CST) and a new concept of nonstress testing (NST). The NST was based on FHR response associated with fetal movements and was categorized as reactive (normal) or nonreactive (abnormal). The nonreactive fetus was then evaluated with a CST if not contraindicated. During the 24 months, May 1, 1975 to April 30, 1977, a total of 2,422 NSTs were done in 1,169 patients with 1,547 (64 per cent) reactive and 829 (35 per cent) nonreactive. CST was done 939 times, with 851 (90.6 per cent) negative, 29 (3 per cent) positive, 13 (1.4 per cent) equivocal, and 46 (5.0 per cent) unsatisfactory. There were ten (3.3 per cent) perinatal deaths within one week of a negative CST, five (1.0 per cent) within one week of a reactive NST, and two (8.7 per cent) with a positive CST. A reactive NST was as predictive of good outcome as was a negative CST. Analysis of the nonreactive NST showed that two or more accelerations were not associated with abnormal CSTs. Also, some nonreactive fetuses became reactive with oxytocin and had good outcome. These observations were utilized in the development of a newer, shorter NST which allows for fetal stimulation in an attempt to further define fetal well-being.

Risk Factors and Outcome of Varicella-Zoster Virus Pneumonia in Pregnant Women

To determine the factors associated with an increased risk of developing varicella-zoster virus (VZV) pneumonia during pregnancy, a case-control analysis was done in which 18 pregnant women with VZV pneumonia were compared with 72 matched control subjects. VZV infection was identified clinically, and VZV pneumonia was diagnosed by dyspnea and findings on chest radiographs. Of 347 pregnant women with VZV infection, 18 (5.2%) had pneumonia treated with acyclovir, and none died. Mean gestational age at rash onset was 25.8 plus minus 8.8 weeks for patients with pneumonia and 17.7 +/- 10.3 weeks for control subjects, which was not significant in the multivariable model. Women with VZV pneumonia were significantly more likely to be current smokers (odds ratio [OR], 5.1; 95% confidence interval [CI], 1.6-16.7) and to have > or = 100 skin lesions (OR, 15.9; 95% CI, 1.9-130.2). Pregnant women with VZV infection may be more likely to develop varicella pneumonia if they are smokers or manifest > or = 100 skin lesions.

Clinical fetal monitoring

Fetal evaluation during both the antepartum and intrapartum periods is increasing in our quest to improve perinatal morbidity and mortality rates. Currently, continuous electronic fetal heart rate (FHR) monitoring is being used increasingly for fetal surveillance during the intrapartum period. Assessment of the possible benefits of clinical monitoring is pertinent since this technique requires capital expenditure, educational programs, and increased patient surveillance. The absolute proof of perinatal benefit is difficult since there is a lack of clear-cut, measurable end points which denote success or failure. Perinatal death is fortunately infrequent, but its occasional occurrence does provide an acceptable end point which can be evaluated. In order to evaluate the possible effects of clinical monitoring, the perinatal mortality rate in a large monitored group was compared with that in an unmonitored group. The incidence of intrapartum fetal and neonatal death was compared in these two groups. The monitored group was comprised of patients with “high-risk” obstetric problems who should have contributed heavily to over-all perinatal deaths. However, comparison revealed that the perinatal outcome was better in the monitored than in the unmonitored group. Although clinical fetal monitoring seems to provide some immediate perinatal benefit, the over-all impact and potential benefit await critical infant follow-up evaluation.