Increased risk of adverse maternal and infant outcomes among women with renal disease.

We conducted a retrospective population-based study to estimate the risk of adverse maternal and neonatal outcomes in women with a diagnosis of renal disease during pregnancy. One hundred and sixty-nine women with renal disease who gave birth to a singleton infant between 1987 and 1993 were identified through linked Washington State hospital discharge and birth certificate databases. For comparison, 506 women without renal disease matched for year of delivery were selected. Women with renal disease were at increased risk of pre-eclampsia [OR = 7.2, 95% CI 4.2-12.5], preterm labour [OR = 7.9, 95% CI 1.9-32.6], dysfunctional labour [OR = 3.6, 95% CI 1.1-11.5], and caesarean section [OR = 3.1, 95% CI 2.0-4.8]. They were also at increased risk of delivering infants who were small for gestational age [OR = 5.3, 95% CI 2.8-10.0], preterm [OR = 6.1, 95% CI 3.3-11.3], and had 5-minute Apgar scores of less than 7 [OR = 3.9, 95% CI 1.1-14.6]. These associations persisted in analyses restricted to women without chronic hypertension. Women with renal disease and their infants also had median hospital charges that were more than twice those of women without renal disease and were more likely to be hospitalised longer. These data demonstrate that, independent of chronic hypertension, women with underlying renal disease are at increased risk of adverse maternal and perinatal outcomes and use more resources than women without renal disease.

Interspecialty differences in the obstetric care of low-risk women.

OBJECTIVES: This study examined differences among obstetricians, family physicians, and certified nurse-midwives in the patterns of obstetric care provided to low-risk patients. METHODS: For a random sample of Washington State obstetrician-gynecologists, family physicians, and certified nurse-midwives, records of a random sample of their low-risk patients beginning care between September 1, 1988, and August 31, 1989, were abstracted. RESULTS: Certified nurse-midwives were less likely to use continuous electronic fetal monitoring and had lower rates of labor induction or augmentation than physicians. Certified nurse-midwives also were less likely than physicians to use epidural anesthesia. The cesarean section rate for patients of certified nurse-midwives was 8.8% vs 13.6% for obstetricians and 15.1% for family physicians. Certified nurse-midwives used 12.2% fewer resources. There was little difference between the practice patterns of obstetricians and family physicians. CONCLUSIONS: The low-risk patients of certified nurse-midwives in Washington State received fewer obstetrical interventions than similar patients cared for by obstetrician-gynecologists or family physicians. These differences are associated with lower cesarean section rates and less resource use.

Nitrofurantoin-induced pulmonary toxicity during pregnancy: a report of a case and review of the literature.

Acute pulmonary reactions to nitrofurantoin are an uncommon side effect of therapy and can cause minor or life-threatening pulmonary dysfunction. Symptoms include fever, chills, cough, pleuritic chest pain, dyspnea. Rarely, pleural effusion and/or pulmonary hemorrhage may occur. Diagnosis is made by clinical suspicion and exclusion of other causes of respiratory compromise. Bronchoalveolar lavage (BAL) may be used to rule out infectious etiologies, and an increase in BAL fluid eosinophils is suggestive of drug-induced toxicity. The acute reaction to nitrofurantoin is believed to be mediated by an immune mechanism. Treatment is mainly discontinuation of the drug, however, corticosteroid therapy is recommended for severe reactions. A chronic reaction associated with long-term treatment with nitrofurantoin has also been reported and causes irreversible pulmonary fibrosis. Nitrofurantoin is commonly used to treat urinary tract infections during pregnancy. Despite the known pulmonary side effects of nitrofurantoin, there is no report of this toxicity occurring in pregnant patients. We present a case of respiratory failure occurring in a woman at 16 weeks' gestation who was being treated with nitrofurantoin for a urinary tract infection.

Bacteremia shortly after placental separation during cesarean delivery.

OBJECTIVE: To assess frequency, risk factors, and microbiology of bacteremia within 15 minutes of placental separation during cesarean delivery. METHODS: Ninety-three women undergoing cesarean delivery after a minimum of 4 hours of labor or ruptured membranes were compared with 26 women not in labor undergoing cesarean. Blood cultures for aerobic and anaerobic bacteria were obtained within 15 minutes of delivery of the placenta and before prophylactic antibiotic administration. Chorioamnionic membranes were also cultured. Demographic, labor, delivery, and postpartum characteristics were abstracted from the medical record. RESULTS: Bacteremia was detected in 13 (11%) of 119 women. Bacteremia occurred in 13 (14%) of 93 women after labor or rupture of membranes compared with zero of 26 women not in labor (P = .02). Isolates included group B streptococcus (n = 5), Gardnerella vaginalis (n = 5), Streptococcus pneumoniae (n = 1), Peptostreptococcus sp (n = 1), and mixed flora of Prevotella bivia, G vaginalis, and viridans streptococci (n = 1). Bacteremia was associated with earlier median gestational age, lower median birth weight, and a positive chorioamnionic membrane culture. After adjustment for gestational age, intrauterine monitoring was also significantly associated with bacteremia. CONCLUSION: Bacteremia was common after labor in this population, especially in preterm deliveries and those with positive chorioamnionic-placental culture. Many of the isolates are capable of causing endocarditis. Appraisal of the risk of bacteremia and the risk of bacterial endocarditis should be made in individual patients to assess the need for antibiotic prophylaxis.

A multicenter evaluation of intramuscular ritodrine hydrochloride as initial parenteral therapy for preterm labor management.

Ninety-four patients in documented preterm labor received three intramuscular injections of ritodrine hydrochloride over an interval of 6 hours. They subsequently received the tocolytic agent intravenously for a minimum of 6 hours. The effects of ritodrine on uterine activity and the cardiovascular system were determined. Intramuscular ritodrine hydrochloride elicited a prompt and sustained reduction in the frequency of uterine contractions. The transition to intravenous treatment was achieved without an increase in uterine activity. Seventy percent of the patients had a sustained interval of uterine quiescence, and 96% had at least a 24-hour delay in delivery. Initial parenteral therapy with intramuscular ritodrine hydrochloride is safe and effective and may provide an alternative to intravenous therapy and a means of managing preterm labor during interhospital transport of a patient.

Risk factors and infant outcomes associated with umbilical cord prolapse: a population-based case-control study among births in Washington State.

OBJECTIVE: Our goal was to quantify the magnitude of risk associated with conditions resulting in umbilical cord prolapse and adverse infant outcome after cord prolapse. STUDY DESIGN: This population-based case-control study used birth certificate data from 709 cases and 2407 randomly selected controls. Odds ratios were used as measures of association, with stratification performed to control for confounding. RESULTS: Case infants were more likely to weigh < 2500 mg (odds ratio 4.8, 95% confidence interval 3.7 to 6.2) and to born prematurely (odds ratio 2.9, 95% confidence interval 2.2 to 3.7). Other risk factors were breech presentation (birth weight-adjusted odds ratio 2.5, 95% confidence interval 1.7 to 3.9) and being a second-born twin (odds ratio 5.0, 95% confidence interval 3.3 to 11.7). Subsequent adverse infant outcomes included an increased risk of mortality (relative risk 2.7, 95% confidence interval 1.9 to 4.0), with mortality being less likely to occur among cases delivered by cesarean section (relative risk 0.4, 95% confidence interval 0.2 to 0.6). CONCLUSIONS: This study confirms previously suspected risk factors and supports clinical management of cord prolapse by cesarean section delivery.

Meningomyelocele: management in utero and post natum.

We report a four year follow-up of 39 of 47 infants born after pre-labour Caesarean section and 68 of 79 born vaginally. Loss of motor function due to late complications was more frequent in the Caesarean section group (Fisher's Exact; P = 0.004). However, the means of the differences between the X-ray levels (measured as the last intact vertebral arch seen on standard anteroposterior roentgenograms of the spinal column) subtracted from the motor levels still favour Caesarean section (mean = 3.24; SD = 2.7) over vaginal delivery (mean = 1.2; SD = 2.7) (Student's t-test; P = 0.0003). The frequencies of other complications, death and neonatal meningitis, were not significantly different. Another 38 infants born by Caesarean section after labour were more paralysed (mean of X-ray and motor difference = 1.8, SD = 2.2) following rupture of amniotic membranes than those with intact amniotic membranes with or without labour (mean = 3.4; SD = 2.2) (Student's t-test; P = 0.0067). The differences between X-ray and motor levels for patients born by Caesarean section with intact amniotic membranes and without labour (mean = 3.6; SD = 2.4) were not significantly different from those with labour and intact amniotic membranes (mean = 2.89; SD = 1.5). The number of new cases of meningomyelocele presenting to our clinic has decreased from an average of 30 per year between 1970 and 1987 to 14 between 1988 and 1992.

The hemodynamic effects of isometric exercise during late normal pregnancy.

OBJECTIVE: Our study was designed to evaluate the hemodynamic effects of isometric exercise in late normal pregnancy. STUDY DESIGN: Study subjects were 10 healthy pregnant volunteers with uncomplicated singleton gestations between 25 and 36 weeks. Doppler methods were used to derive cardiac output, total peripheral resistance, and stroke volume before, during, and after a defined protocol of lower extremity isometric exercise. Hemodynamics and blood pressure were evaluated and compared. RESULTS: Mean arterial blood pressure and total peripheral resistance increased during the performance of isometric effort (mean blood pressure +/- SD was 78.9 +/- 7.3 to 97.5 +/- 8.6 mm Hg; total peripheral resistance +/- SD was 924 +/- 148 to 1153 +/- 18.3 dyne.sec.cm-5; p < 0.002 and p < 0.001, respectively). Cardiac output remained unchanged throughout the study period. CONCLUSION: In advanced normal pregnancy isometric exercise increases the mean arterial blood pressure by raising the total peripheral resistance.

Influence of diagnostic criteria on the incidence of gestational diabetes and perinatal morbidity.

OBJECTIVE: To determine the incidence of gestational diabetes and its associated maternal and infant morbidity by two sets of 3-hour glucose tolerance test criteria, those recommended by the National Diabetes Data Group or the lower, modified criteria of Carpenter and Coustan. DESIGN: Prospective, observational outcome cohort study. SETTING: Prepaid health maintenance organization. SUBJECTS: A total of 2019 pregnant women preregistered in a health maintenance organization were screened for a plasma glucose of 7.77 mmol/L (140 mg/dL) or greater, 1 hour after ingestion of a 50-g glucose drink administered after an overnight fast. Positive subjects received a 3-hour glucose tolerance test interpreted by the two criteria. Data are presented for 521 randomly selected negative screenees; 264 positive screen, negative glucose tolerance test subjects; and 101 subjects with gestational diabetes mellitus. OUTCOME MEASURES: Maternal risk factors for diabetes, infant birth weight corrected for gestational age (birth-weight ratio), umbilical cord serum insulin levels, and 33 maternal and infant perinatal morbidities assessed from chart review. RESULTS: Gestational diabetes incidence was 5.0% overall based on the modified criteria and 3.2% by the recommended criteria. Maternal age and family history of diabetes were higher in both modified and recommended groups. Birthweight ratio was 1.05 in negative screenees, 1.09 in gestational diabetes overall (P < .05 when only diet-treated subjects were considered), and 1.11 in modified and 1.08 in recommended criteria groups. Cord serum insulin levels in infants of gestational diabetic mothers by both criteria were 40% above those of negative screenees (P < .001). The average percentage incidence of 33 possible perinatal morbidities was 41% higher in gestational diabetic pregnancies by the modified criteria. The cumulative number of morbidities was higher in both modified and recommended criteria groups (P < .01 in both instances). In contrast, subjects having a positive glucose screening test but a negative glucose tolerance test by modified criteria had none of the characteristics of gestational diabetes with the single exception of greater age. CONCLUSIONS: Fifty percent more cases of gestational diabetes were identified using the more inclusive, modified criteria. These cases had as much excess in maternal diabetes risk factors, infant macrosomia, and cord hyperinsulinemia and nearly as much increase in perinatal morbidity as subjects diagnosed by the recommended criteria. The incidence and perinatal impact of gestational diabetes may be greater than previously appreciated. The modified criteria deserve wider verification and use.

Prediction of infant birth weight by GDM screening tests. Importance of plasma triglyceride.

OBJECTIVE: We measured plasma glucose, GHb, GPro, IRI and TG at 24-28-wk gestation to determine the extent of elevations in GDM and relationships to glucose intolerance and infant macrosomia. RESEARCH DESIGN AND METHODS: Plasma samples were obtained 1 h after ingestion of 50 g glucose after an overnight fast in 521 randomly selected negative screenees, 264 positive screenees with GTT-, and 96 positive screenees with GTT+ (GDM). RESULTS: Screening test values in GDM subjects exceeded the GTT- group, whose values exceeded those of negative screenees: glucose, 9.6*, 8.7*, 6.3 mM; GHb, 5.2*, 4.9*, 4.7%; GPro, 3.1*, 3.0*, 2.8%; IRI, 791*, 662*, 410 pM; and TG, 2.3*, 1.9, 1.9 mM, (*P < 0.005 vs. negative screenees). TG was the only test elevated in the GDM but not in the GTT- groups. Screening test values correlated with GTT values in the following order (strongest to weakest): glucose* > TG* > GHb* > IRI > GPro (*statistical significance). Plasma TG was the only screening test significantly associated with birth weight corrected for gestational age (birth-weight ratio) (r = 0.09-0.16) (P < 0.05 to < 0.01) and was of the same order as 1- and 2-h GTT associations with birth weight (r = 0.13 and 0.14, respectively) (P < 0.05 to < 0.01). Plots of TG/birth-weight ratio increased linearly to the 80-90th TG percentile in negative screenees and GTT- subjects. GDM subjects followed this trend but with more variation. Above the 90th percentile for TGs, birth-weight ratio trended lower, significantly so when the groups were combined (P < 0.05). In multivariate analysis, TG was associated with birth-weight ratio even when maternal prepregnancy weight and pregnancy weight gain associations with TG and birth-weight ratio were controlled (P < 0.019). CONCLUSIONS: Of the five screening tests evaluated, all were elevated in GDM, but TG is the best discriminator of GDM from the GTT- group, and it is the only test significantly related to birth-weight ratio--and to glucose intolerance besides glucose itself. The TG association with birth weight is not explained fully by maternal weight. The results suggest that plasma TG may be a physiological contributor to infant birth weight. Further evaluation of plasma TG in GDM screening is justified, but GHb, GPro, and IRI appear to hold less promise.

Clinical evaluation of the NBD-PC fluorescence polarization assay for prediction of fetal lung maturity.

OBJECTIVES: 1) To examine a fluorescence polarization (FP) assay with an independent set of data that contained more cases of respiratory distress syndrome (RDS) than a previous study, 2) to determine whether the same reference ranges are applicable to infants born to diabetic women, and 3) to evaluate whether adding the lecithin-sphingomyelin ratio (L/S) would substantially improve the prediction of RDS among women with an intermediate FP value (between 0.26-0.289). METHODS: We identified 389 women who had FP analysis performed at the University of Washington Medical Center from February 1986 to October 1988 and who delivered within 3 days of amniocentesis. We reviewed the medical records of these women and their infants to extract information for our study. RESULTS: For FP values of 0.26 or greater, the sensitivity and specificity for prediction of RDS were 90.2 and 84.6%, respectively, compared with 100 and 82.0% in the previous study. For FP values of 0.29 or greater, the sensitivity and specificity were 62.8 and 94.2%, respectively (80.8 and 96.2% in the previous study). Among diabetics, an FP result below 0.26 was associated with the same low risk of RDS as among non-diabetics. Among the patients with FP between 0.26-0.289, the addition of L/S did not provide a clinically useful improvement in the prediction of fetal lung maturity. CONCLUSION: The NBD-PC FP assay can be used as the sole test of fetal lung maturity in most clinical circumstances.

Hemodynamics associated with the diagnosis and treatment of pheochromocytoma in pregnancy.

A pregnant woman with an undiagnosed pheochromocytoma is described. Her presentation at 29 weeks' gestation was consistent with preeclampsia. Noninvasive measurement of cardiac output and ambulatory monitoring of blood pressure provided data that facilitated making the appropriate diagnosis and managing the patient until delivery at term.

Risks associated with pregnancy in spinal cord-injured women.

We reviewed the experience with pregnancy in spinal cord-injured women at the University of Washington over the past 10 years. During that time, 11 women with spinal cord injury had 13 pregnancies. Infant outcome was uniformly good. No major obstetric complication occurred. The mothers experienced medical problems including urinary tract infection in ten and pyelonephritis in three. Autonomic hyperreflexia occurred in three of five subjects with lesions at or above the sixth thoracic vertebra. Pregnancy in the spinal cord-injured patient involves medical risk for the mother, but with careful management, an excellent outcome for both mother and infant may be anticipated.

Effect of orthostatic stress on umbilical Doppler waveforms in normal and hypertensive pregnancies.

OBJECTIVE: Our study examined the effects of orthostatic stress and maternal hemodynamics on umbilical systolic/diastolic ratios in normal and hypertensive pregnancies. STUDY DESIGN: Eighteen normal and 20 hypertensive third-trimester pregnancies were examined in the left lateral recumbent, sitting, and standing positions. Measurements included umbilical systolic/diastolic ratio, maternal blood pressure, maternal cardiac output, and maternal total peripheral resistance. RESULTS: All patients demonstrated a fall in cardiac output and a rise in total peripheral resistance with standing. No change in systolic/diastolic ratio occurred with change to the upright position in patients with normotension. Patients with hypertension exhibited a significant increase in umbilical systolic/diastolic ratio with postural change. The increase was more marked in women who had hypertension with elevated peripheral resistance. CONCLUSION: Patients with hypertension are at increased risk of elevation of systolic/diastolic ratio with postural change; women with high-resistance hypertension may be at highest risk.

Amyl nitrite: use as a smooth muscle relaxant in difficult preterm cesarean section.

Amyl nitrite is a smooth muscle relaxant that has been used clinically to facilitate uterine relaxation in difficult deliveries. In this retrospective study, we evaluate the safety of amyl nitrite use during preterm cesarean deliveries, and we assess possible advantageous effects on surgical incision choice. Women who received amyl nitrite cesarean section were compared to a control group matched for gestational age, fetal presentation, and mode of delivery who did not receive amyl nitrite. There were no statistical differences between the groups in the independent variables (maternal age, parity, medical or obstetric history, type of anesthesia, anesthesia or obstetric attending physician, antepartum hematocrit, or neonatal weight). Outcome (dependent) variables (estimated blood loss, Apgar scores, postpartum hematocrit, cord gases, or postpartum complications) were assessed, and there were no significant differences between the groups. Low transverse cesarean section was performed more frequently in the amyl nitrite group (58 of 64) than in the comparison group (48 of 64) (p less than 0.03). Considering the 128 women with and without amyl nitrite together, the decrease in hematocrit observed postpartum was greater after classic section (7%) than after low transverse section (4%) (p less than 0.002). We conclude that the use of amyl nitrite during preterm cesarean section poses no threat to mother or fetus and may facilitate delivery by allowing the performance of a low transverse rather than a classic cesarean section without maternal or neonatal complications.

The maternal hemodynamic effect of indomethacin in normal pregnancy.

The vasodilation of pregnancy is thought by many to be due to increased endothelial production of prostacyclin, a vasodilatory prostanoid. Indomethacin, a potent inhibitor of prostaglandin synthesis, is known to increase the maternal blood pressure response to angiotensin II infusion. We sought to measure directly the hemodynamic effects of a short course of indomethacin. Twenty-three healthy pregnant women with uncomplicated pregnancies between 26-32 weeks' gestation completed the study. Using Doppler technology, we determined cardiac output, stroke volume, and total peripheral resistance before and after three 25-mg doses of indomethacin. Although blood pressure did not change, peripheral resistance rose and stroke volume fell following indomethacin administration. Our findings support the hypothesis that indomethacin interferes with tonic prostaglandin-induced vasodilation in pregnancy. However, the increase in vascular resistance was very slight, suggesting that other vasodilators are also at work in pregnancy. We recommend that indomethacin be used judiciously in hypertensive pregnant patients until more information concerning possible adverse hemodynamic effects becomes available.

Expectant management after sonographic diagnosis of placental abruption.

Forty cases of placental abruption were diagnosed by sonography after 20 weeks' gestation and managed expectantly. Tocolytics were used in 18 patients and were successful in delaying delivery for 34 +/- 24 days in 10. One-third of the patients delivered at term, after delays of 12.3 +/- 5.7 weeks. The majority of the patients who delivered before term (63%) had at least one other risk factor for preterm delivery, such as twins, ruptured membranes, or cervical dilation at presentation. Preterm delivery was not correlated with any of several clinical indicators of the severity of the abruption. Although the perinatal mortality rate was 22%, all perinatal deaths except one were attributable to extreme prematurity. It concluded that mild placental abruption is often a self-limited event and can safely be managed expectantly. Most of the perinatal morbidity and mortality is associated with premature delivery and, thus, in the absence of fetal distress or maternal compromise, delivery may often be delayed until fetal maturity is attained.

Antiepileptics and the development of congenital anomalies.

We are conducting a prospective cohort study of epilepsy and pregnancy to determine the nature and extent of adverse pregnancy outcomes in infants of mothers with epilepsy (IME). Women with epilepsy were enrolled no later than the first trimester and were matched with controls; their infants were examined at 8 weeks by pediatricians blinded to maternal status. A number of variables were compared between case and control infants: birth weight, length, gestational age, head circumference, Apgar scores, feeding difficulties, neonatal irritability, and presence of major malformations and minor anomalies. The number of minor anomalies per infant was greater for IME than for controls (mean, 5.05 and 3.65, p less than 0.0001 per infant, respectively). Prominent occiput was the only anomaly seen significantly more often in IME than in controls (p less than 0.05).