Length of the second stage of labor and preterm delivery risk in the subsequent pregnancy.

BACKGROUND: Cervical injury is regarded as an important risk factor for preterm delivery. A prolonged second stage of labor may increase the risk of cervical injury that, in turn, may be associated with increased risk of spontaneous preterm delivery in the subsequent pregnancy. OBJECTIVE: We sought to evaluate whether the duration of the second stage of labor in a term primiparous singleton delivery is associated with an increased risk of singleton spontaneous preterm delivery (<37 weeks) in the second pregnancy. STUDY DESIGN: We carried out a retrospective cohort analysis of women with 2 consecutive pregnancies: a first term (≥37 weeks) delivery and second birth. Data were derived from a single institution's prospectively collected obstetrical database from January 2005 through January 2015. Duration of the second stage of labor was examined as a continuous variable, modeled based on nonparametric restricted cubic regression spline with 4 degrees of freedom. Second-stage duration was also examined as short (<30 minutes), normal (30-179 minutes), and prolonged, defined as ≥180 minutes. The association between the duration of the second stage of labor in the first term pregnancy and the risk for spontaneous preterm delivery in the second pregnancy was evaluated before and after adjusting for potential confounders based on the Cox proportional hazards regression model. Associations were expressed based on the adjusted hazard ratio and 95% confidence interval. RESULTS: In all, 6715 women met inclusion criteria. The hazard of spontaneous preterm delivery in the second pregnancy trended higher with both shorter and longer second-stage labors. The length of the second stage of labor in the first term delivery was categorized as short (<30 minutes) in 1749 (26.0%), normal (30-179 minutes) in 4551 (67.8%), and prolonged (≥180 minutes), in 415 (6.2%) women. Of these 6715 women with a first term delivery, 4.2% (n = 279) delivered spontaneously preterm in the second pregnancy. The risks of spontaneous preterm delivery among women with prolonged (≥180 minutes) second stage of labor and normal labor duration (30-179 minutes) were 5.4% (n = 22) and 3.5% (n = 158), respectively (adjusted hazard ratio, 1.81; 95% confidence interval, 1.15-2.84). This increased risk for prolonged second stage of labor was primarily seen among women who underwent a cesarean (hazard ratio, 3.38; 95% confidence interval, 1.09-10.49), but was imprecise among women who delivered vaginally (hazard ratio, 1.52; 95% confidence interval, 0.62-3.74). The risk of spontaneous preterm delivery among women with short second stage of labor (<30 minutes) in their first term pregnancy was 5.8% (n = 99; hazard ratio, 1.28; 95% confidence interval, 0.99-1.67). CONCLUSION: The risk of spontaneous preterm delivery in the second pregnancy was increased in women with a prolonged (≥180 minutes) second stage in the first term pregnancy. This risk was even greater among women who were delivered by cesarean in the first pregnancy.

Treatment of a Pregnant Patient in a Persistent Vegetative State.

BACKGROUND: Brain injury leading to a persistent vegetative state during pregnancy involves difficult medical and ethical decisions. CASE: A 21-year-old multigravid woman entered a persistent vegetative state at 20 1/7 weeks of gestation after cardiac arrest with postanoxic brain injury from a suspected drug overdose. The clinical disciplines responsible for her case formed a collaborative care plan involving ventilator, nutrition, and medication support of the mother and regular fetal monitoring and ultrasound testing. A planned delivery by cesarean at term resulted in a good neonatal outcome. CONCLUSION: There is no standardized management plan for obstetric care in a persistent vegetative state. This case illustrates a successful multidisciplinary approach that may be useful as a template in similar situations.

Invasive placental disease: the impact of a multi-disciplinary team approach to management.

PURPOSE: To determine the impact of a structured multi-disciplinary management strategy on clinical outcomes in women with invasive placental disease (IPD). MATERIALS AND METHODS: This was a retrospective cohort study of consecutive women having peripartum hysterectomies with IPD over seven years. For the most recent three years, a structured multidisciplinary team (MDT) reviewed each suspected case, created a management plan, and implemented that plan. Outcomes were compared between cases delivered prior to and after the MDT process was started. RESULTS: There were 47 pregnancies with IPD, of which 31 (66.0%) were suspected antenatally and 40 (85.1%) had a prior uterine surgery. An MDT approach was performed in 19 (40.4%) cases. In the MDT group, there were longer operative times (260 min versus 181 min, p = 0.0001), less blood loss (1200 mL versus 2500 mL, p = 0.009), less administration of blood products (47.4% versus 85.7%, p = 0.005), and higher intraoperative lowest mean arterial pressures (MAPs) (57 mmHg versus 48 mmHg, p = 0.002, when compared to the No-MDT (n = 28) approach. No differences were found for other outcomes. CONCLUSION: Clinically meaningful improvements of less blood loss, fewer transfusions, and higher intraoperative MAPs suggest that MDT cases were more stable intraoperatively, which over a larger number of patients, should translate into improved outcomes.

Use of intracervical balloons and chorioamnionitis in term premature rupture of membranes.

OBJECTIVE: To determine whether ripening and induction in patients with term premature rupture of membranes (PROM) via intracervical balloon placement (ICB) increases the risk of chorioamnionitis when compared to women with term PROM ripened and induced with other methods. STUDY DESIGN: A retrospective cohort study of term singleton gestations undergoing ripening and induction after PROM between July 2009 and June 2012 was conducted. Exposure of interest was ICB placement. Primary outcome of interest was chorioamnionitis. Statistical analysis included bivariate and multivariate techniques. RESULTS: Of 124 term PROM patients, 42 were ripened by ICB with or without oxytocin (33.9%) and 82 were ripened and induced with oxytocin (66.1%). More women ripened with an ICB were nulliparous (n = 35, 83.3% ICB versus n = 44, 53.7% oxytocin, p = 0.001). Chorioamnionitis was slightly more common in women ripened with ICB and/or oxytocin versus oxytocin alone but difference did not reach statistical significance (p = 0.10). The rate of cesarean delivery, intrauterine pressure catheter (IUPC) use, and median lengths of membrane rupture and active labor were higher in the ICB group. After adjustment, chorioamnionitis was not correlated with ICB placement but with nulliparity [AOR 12.5 (1.36, 114.6), p = 0.03] and IUPC use [AOR 4.39 (1.04, 18.5), p = 0.04]. CONCLUSION: Nulliparity and IUPC, not ICB placement, were associated with chorioamnionitis.

Clinical evaluation during postpartum hemorrhage.

Obstetric hemorrhage remains the most important cause of maternal mortality worldwide, accounting for 30% of all direct maternal deaths. As the method of management depends on multiple concurrent and sequential evaluations of the patient's status, it is helpful to have an evaluation strategy prepared for when a postpartum hemorrhage is encountered to facilitate interventions. This review describes an etiology-based approach to the clinical evaluation of postpartum hemorrhage and a suggested systems process that allows both a timely and appropriate evaluation of the hemorrhaging mother.

Postpartum hemorrhage.

Postpartum hemorrhage (PPH) is the leading cause of death related to pregnancy worldwide. Most deaths resulting from PPH are preventable. Physicians, nurses, midwives, and other birth attendants should be aware of the risk factors for PPH and be trained adequately in the preventive measures and management strategies for this pregnancy complication. Newer, less invasive technologies such as embolization may improve outcomes with PPH. Reducing the incidence of PPH and the mortality resulting from the condition should be a key goal of obstetrics services worldwide. This article focuses on the etiology, prediction, prevention, and management of PPH.

Changes in prepregnancy body mass index between the first and second pregnancies and risk of large-for-gestational-age birth.

OBJECTIVE: The objective of our study was to determine whether changes in prepregnancy body mass index (BMI) between the first 2 pregnancies is associated with increased risk for large-for-gestational-age (LGA) birth in the second pregnancy. STUDY DESIGN: A population-based, retrospective cohort analysis was performed using the Missouri 1989-1997 longitudinally linked data. Women with the first 2 consecutive singleton live births (n = 146,227) were analyzed. BMI (kilograms per square meter) was categorized as underweight (less than 18.5), normal (18.5 to 24.9), overweight (25 to 29.9), and obese (30 or greater), and LGA was defined as gestational age-specific birthweight greater than the 90th centile. Multivariate logistic regression analysis was used to estimate the odds ratio (OR) with 95% confidence interval (CI). Population attributable fraction for LGA births was calculated. RESULTS: Compared to women with normal BMI in their first and second pregnancies, overweight-overweight (OR 1.7, 95% CI 1.6, 1.8) and obese-obese (OR 2.3, 95% CI 2.2, 2.4) women in their first and second pregnancies were at increased risk of LGA births. Any increase in BMI from normal to obese between pregnancies increased LGA risk (OR 1.6 to 2.0), whereas any decrease in BMI from obese to normal attenuated the risk (OR 1.3 to 1.7). 17.1%, 13.2%, and 7.6% of LGA births are likely preventable had BMI not increased from first pregnancy underweight, normal, and overweight, respectively. CONCLUSION: In comparison with women with normal BMI in both pregnancies, any increase or decrease in prepregnancy BMI between normal and obese is associated with increased risk of LGA birth. A modification in the risk of LGA births by long-term maternal BMI status or maternal genetic factors appears likely.

Balloon-assisted occlusion of the internal iliac arteries in patients with placenta accreta/percreta.

BACKGROUND: Placenta accreta/percreta is a leading cause of third trimester hemorrhage and postpartum maternal death. The current treatment for third trimester hemorrhage due to placenta accreta/percreta is cesarean hysterectomy, which may be complicated by large volume blood loss. PURPOSE: To determine what role, if any, prophylactic temporary balloon occlusion and transcatheter embolization of the anterior division of the internal iliac arteries plays in the management of patients with placenta accreta/percreta. METHODS: The records of 28 consecutive patients with a diagnosis of placenta accreta/percreta were retrospectively reviewed. Patients were divided into two groups. Six patients underwent prophylactic temporary balloon occlusion, followed by cesarean section, transcatheter embolization of the anterior division of the internal iliac arteries and cesarean hysterectomy (n = 5) or uterine curettage (n = 1). Twenty-two patients underwent cesarean hysterectomy without endovascular intervention. The following parameters were compared in the two groups: patient age, gravidity, parity, gestational age at delivery, days in the intensive care unit after delivery, total hospital days, volume of transfused blood products, volume of fluid replacement intraoperatively, operating room time, estimated blood loss, and postoperative morbidity and mortality. RESULTS: Patients in the embolization group had more frequent episodes of third trimester bleeding requiring admission and bedrest prior to delivery (16.7 days vs. 2.9 days), resulting in significantly more hospitalization time in the embolization group (23 days vs. 8.8 days) and delivery at an earlier gestational age than in those in the surgical group (32.5 weeks). There was no statistical difference in mean estimated blood loss, volume of replaced blood products, fluid replacement needs, operating room time or postoperative recovery time. CONCLUSION: Our findings do not support the contention that in patients with placenta accreta/percreta, prophylactic temporary balloon occlusion and embolization prior to hysterectomy diminishes intraoperative blood loss.

A clinicohistopathologic comparison between HELLP syndrome and severe preeclampsia.

OBJECTIVE: To determine whether differences in the clinical entities of HELLP syndrome and severe preeclampsia are associated with different placental lesions. STUDY DESIGN: This was a case control study of singleton pregnancies with HELLP syndrome or severe preeclampsia. Archived pathology slides were retrieved and reviewed. Clinical and histopathological features were compared between the two groups. RESULTS: There were 31 women with HELLP syndrome and 56 with severe preeclampsia. HELLP syndrome was associated with epigastric pain and higher levels of LDH, bilirubin, liver enzymes and fibrin degradation products. Hemoglobin, hematocrit and platelet counts were lower. Abruption lesions of the placenta were less common with HELLP syndrome (Odds Ratio 0.1 95% Confidence Interval 0.01,0.8). None of the other 22 placental features examined were different between the two conditions. CONCLUSION: The significant overlap between HELLP syndrome and severe preeclampsia for both clinical and placental features suggests that the two conditions represent a spectrum of essentially the same pathophysiologic process.

Obstetric admissions to the intensive care unit: outcomes and severity of illness.

OBJECTIVE: To determine whether mortality prediction based on a current model of outcome prediction is accurate in obstetric patients. METHODS: Consecutive obstetric admissions to a medical intensive care unit from 1991 to 1998 were reviewed to determine whether mortality prediction is feasible in obstetric patients based on a widely used model. The Simplified Acute Physiologic Score (SAPS II) was used to predict the probability of hospital mortality. RESULTS: The Simplified Acute Physiologic Score overestimated mortality in all patients (19 predicted deaths, eight observed) but accurately predicted mortality in patients admitted to the intensive care unit for medical reasons (seven predicted, five observed). The Simplified Acute Physiologic Score did not predict mortality in patients admitted for obstetric indications or postpartum hemorrhage. Median SAPS II scores were significantly higher in those patients who died, compared with survivors. For all groups, SAPS II scores were correlated with intensive care unit length of stay but not hospital length of stay. CONCLUSION: The Simplified Acute Physiologic Score accurately predicts hospital mortality in obstetric patients admitted to the intensive care unit for medical reasons but not for indications related to pregnancy and delivery. An alternate model that predicts outcomes in obstetric patients admitted for obstetric indications should be developed.

The impact of prenatal care on preterm births among twin gestations in the United States, 1989-2000.

OBJECTIVE: The purpose of this study was to determine the association between prenatal care and preterm births among twin gestations in the presence and absence of high-risk pregnancy conditions. STUDY DESIGN: Twin birth data in the United States were used to determine the association between preterm birth and prenatal care with the use of logistic regression. RESULTS: Of the 779,387 twin births, 54.7% twin births were delivered preterm. The rate was higher among black women than among white women in the presence (57.0% vs 51.2%, respectively) and absence (70.3% vs 61.6%, respectively) of prenatal care. The absence of prenatal care increased the relative risk for preterm birth by 1.24-fold among black women and by 1.22-fold among white women. Lack of prenatal care was associated with increased preterm birth rates in the presence of most high-risk conditions. CONCLUSION: Prenatal care is associated with fewer twin preterm births in the presence and absence of high-risk conditions. Increased prenatal care participation may help decrease preterm birth rates and also narrow the black-white twin preterm birth disparity.

Fetal deaths in the United States. Influence of high-risk conditions and implications for management.

OBJECTIVE: To estimate the effect of specific maternal-fetal high-risk conditions on the risk and timing of fetal death. METHODS: This study examined 10,614,679 non-anomalous singleton pregnancies delivering at or beyond 24 weeks' gestation, derived from the U.S. linked birth/infant death data sets, 1995-1997. Fetal death rates for pregnancies at low risk were compared with pregnancies complicated by chronic hypertension, gestational hypertensive disorders, diabetes, small for gestational age infants, and abruption. Adjusted relative risks as well as population-attributable risks for fetal death were derived by gestational age for each high-risk condition compared with low-risk pregnancies. RESULTS: The fetal death rate for low-risk pregnancies was 1.6 per 1000 births. Adjusted relative risk for fetal death was 9.2 (95% confidence interval [CI] 8.8, 9.7) for abruption, 7.0 (95% CI 6.8, 7.2) for small for gestational age infants, 1.4 (95% CI 1.3, 1.5) for gestational hypertensive disorders, 2.7 (95% CI 2.4, 3.0) for chronic hypertension, and 2.5 (95% CI 2.3, 2.7) for diabetes. Fetal death rates were lowest between 38 and 41 weeks. The fetal death rate (per 1000 births) for these high-risk conditions was 61.4, 9.6, 3.5, 7.6, and 3.9, respectively. Almost two thirds of fetal deaths were attributable to the pregnancy complications examined. CONCLUSION: High-risk conditions in pregnancy are associated with an increased risk for fetal death, particularly in the third trimester. Delivery should be considered at 38 weeks, but no later than 41 weeks, for these pregnancies.

Atrial fibrillation in pregnancy associated with oral terbutaline.

BACKGROUND: Terbutaline has direct effects on the cardiac conduction system, but when used to treat preterm labor it is rarely associated with clinically significant cardiac arrhythmias. Commonly used drug references did not list atrial fibrillation as a complication of terbutaline, and our literature search found only one case of atrial fibrillation that occurred with parenteral administration. CASE: A 30-year-old gravida 1 carrying a twin gestation at 35 weeks was taking 2.5 mg oral terbutaline four times daily for premature labor. She developed atrial fibrillation and was ultimately treated by chemical cardioversion with procainamide to restore normal sinus rhythm. CONCLUSION: This is the first report of atrial fibrillation during pregnancy associated with oral terbutaline. Atrial fibrillation should be added as a complication of oral terbutaline therapy.

Down syndrome risk estimation after normal genetic sonography.

OBJECTIVE: The objective of this study was to determine whether there are any indication-specific variations in risk reduction for fetal Down syndrome after a normal genetic sonogram. STUDY DESIGN: A second-trimester genetic sonogram was offered to all pregnant women who were at increased risk for fetal Down syndrome (>/=1:274) because of either advanced maternal age (>/=35 years), an abnormal triple screen, or both. Outcome information included the results of genetic amniocentesis (if performed), the results of pediatric assessment, and follow-up after birth. Normal genetic sonography was defined as the absence of all ultrasound aneuploidy markers. RESULTS: The overall prevalence of fetal Down syndrome in the tested population was 1.41% (53/3,753 pregnancies); however, in the presence of normal genetic sonography, the overall prevalence of fetal Down syndrome was 0.21% (7/3,291 pregnancies). The overall risk reduction for fetal Down syndrome in the presence of normal genetic sonography was 6.64-fold (95% CI, 3.01-14.62); the overall negative likelihood ratio was 0.15 (95% CI, 0.07-0.33). In the presence of normal genetic sonography, the risk for fetal Down syndrome was reduced by 83% in patients with advanced maternal age, 88% in patients with abnormal triple screen, 89% in patients with abnormal triple screen who were <35 years old, and 84% in patients who had both abnormal triple screen and advanced maternal age. CONCLUSION: There were no significant variations in the risk reduction for fetal Down syndrome in the presence of normal genetic sonography. Regardless of the indication for testing, the likelihood for fetal Down syndrome was reduced by 83% to 89%. This information will be useful in counseling pregnant women who are at high risk for fetal Down syndrome and who prefer to undergo genetic sonography before deciding about genetic amniocentesis.

The impact of prenatal care in the United States on preterm births in the presence and absence of antenatal high-risk conditions.

OBJECTIVE: This study was undertaken to determine the association between prenatal care in the United States and preterm birth rate in the presence, as well as absence, of high-risk pregnancy conditions for African American and white women. STUDY DESIGN: Data were derived from the natality data set for the years 1995 to 1998 provided by the National Center for Health Statistics. Analyses were restricted to singleton live births that occurred at >/=20 weeks' gestation. Multiple births, fetal deaths, congenital malformations, chromosomal abnormalities, missing data on gestational age, and birth weight less than 500 g were excluded. Multivariable logistic regression analyses were used to adjust for the presence or absence of various antenatal high-risk conditions, maternal age, gravidity, marital status, smoking, alcohol, and education. Prenatal care was considered present if there was one or more prenatal visits. Preterm delivery was defined as delivery at less than 37 completed weeks of gestation. RESULTS: For 14,071,757 births analyzed, 1,348,643 (9.6%) resulted in preterm birth. Preterm birth rates were higher for African American women than white women in the presence (15.1% vs 8.3%) and absence (34.9% vs 21.9%) of prenatal care. The absence of prenatal care increased the relative risk for preterm birth 2.8-fold in both African American and white women. There was an inverse dose-response relationship between the number of prenatal visits and the gestational age at delivery both among African American and white women. Lack of prenatal care was associated with increased preterm birth rates to a similar degree in the presence of pregnancy complications for both African American and white women, ranging from 1.6-fold to 5.5-fold for the various antenatal high-risk conditions. CONCLUSION: In the United States, prenatal care is associated with fewer preterm births in the presence, as well as absence of high-risk conditions for both African American and white women. Strategies to increase prenatal care participation may decrease preterm birth rates.

The impact of prenatal care on postneonatal deaths in the presence and absence of antenatal high-risk conditions.

OBJECTIVE: This study was undertaken to determine the association, if any, between prenatal care and postneonatal death in the presence and absence of high-risk pregnancy conditions. STUDY DESIGN: Data were derived from the national linked birth/infant death data set for the years 1995 to 1997 provided by the National Center for Health Statistics. Analyses were restricted to singleton live births that occurred after 23 completed weeks of gestation. Multiple births, congenital malformations, chromosomal abnormalities, missing data on gestational age, and birth weight less than 500 g were excluded. Multivariable logistic regression analyses were used to adjust for various antenatal high-risk conditions, maternal age, gravidity, gestational age at delivery, birth weight, maternal education, marital status, smoking, and alcohol use. Postneonatal death rate was defined as the number of deaths between 28 and 365 days of life per 1,000 neonatal survivors. RESULTS: For 10,512,269 singleton live births analyzed, 21,962 (2.1 per 1,000) resulted in postneonatal death. Postneonatal death rates were higher for African American women than white women in the presence (3.8 vs 1.7 per 1,000) and absence (11.2 vs 5.3 per 1,000) of prenatal care. Lack of prenatal care was associated with increased relative risk (RR) for postneonatal death, 1.8-fold in African American women and 1.6-fold in white women. Lack of prenatal care was associated with increased postneonatal death rates to a similar degree for the individual high-risk pregnancy conditions for both African American and white women. Lack of prenatal care was associated with increased postneonatal death rates, especially in the presence of postterm pregnancy (RR 2.3, 95% CI 1.6, 3.1), pregnancy-induced hypertension (RR 2.2, 95% CI 1.5, 3.4), intrapartum fever (RR 2.1, 95% CI 1.2, 3.5), and small-for-gestational-age infant (RR 1.6, 95% CI 1.3, 2.0). CONCLUSION: Lack of prenatal care should be considered as a high-risk factor for postneonatal death for both African American and white women, especially if the pregnancy has been complicated by postdates, pregnancy-induced hypertension, intrapartum fever or small-for-gestational-age infant.

Second-trimester genetic sonography in patients with advanced maternal age and normal triple screen.

OBJECTIVE: To estimate the value of second-trimester genetic sonography in detecting fetal Down syndrome in patients with advanced maternal age (at least 35 years) and normal triple screen. METHODS: Since July 1999, a prospective collection and recording of all individual triple screen risks for fetal Down syndrome was initiated for all patients with advanced maternal age presenting in our ultrasound unit for second-trimester genetic sonography. Genetic sonography evaluated the presence or absence of multiple aneuploidy markers. Outcome information included the results of genetic amniocentesis, if performed, and the results of pediatric assessment and follow-up after birth. RESULTS: By June 2001, 959 patients with advanced maternal age and normal triple screen were identified. Outcome information was obtained in 768 patients. The median risk for fetal Down syndrome based on maternal age was 1:213 (range 1:37-1:274). The median risk for fetal Down syndrome based on triple screen results was 1:1069 (range 1:275-1:40,000). A total of 673 patients had normal genetic sonography, and none (0%) had Down syndrome; 95 had one or more aneuploidy markers present, and four (4.2%) had fetuses with Down syndrome. The triple screen risks for these four fetuses ranged from 1:319 to 1:833. CONCLUSION: This study suggests that patients with advanced maternal age and normal genetic sonography carried very little risk for Down syndrome. The use of genetic sonography may increase the detection rate of fetal Down syndrome in this group of pregnant women.

The impact of prenatal care on neonatal deaths in the presence and absence of antenatal high-risk conditions.

OBJECTIVE: The purpose of this study was to determine the association between prenatal care in the United States and the neonatal death rate in the presence and absence of antenatal high-risk conditions. STUDY DESIGN: Data were derived from the national perinatal mortality data sets for the years 1995 through 1997, which were provided by the National Center for Health Statistics. Analyses were restricted to singleton live births that occurred after 23 completed weeks of gestation. Multivariable logistic regression analyses were used to adjust for the presence or absence of various antenatal high-risk conditions, maternal age, gestational age at delivery, and birth weight. RESULTS: Of 10,530,608 singleton live births, 18,339 (1.7/1000 births) resulted in neonatal death. Neonatal death rates (per 1000 live births) were higher for African American infants compared with white infants in the presence (2.7 vs 1.5, respectively) and absence (10.7 vs 7.9, respectively) of prenatal care. Lack of prenatal care was associated with an increase in neonatal deaths, which was greater for infants born at > or =36 weeks of gestation (relative risk, 2.1; 95% CI, 1.8, 2.4). Lack of prenatal care was also associated with increased neonatal death rates in the presence of preterm premature rupture of the membranes (relative risk, 1.3; 95% CI, 1.1, 1.5), placenta previa (relative risk, 1.9; 95% CI, 1.2, 2.9), fetal growth restriction (relative risk, 1.7; 95% CI, 1.2, 1.6), and postterm pregnancy (relative risk, 1.4; 95% CI, 1.0, 2.9). CONCLUSION: In the United States, prenatal care is associated with fewer neonatal deaths in black and white infants. This beneficial effect was more pronounced for births that occurred at > or =36 weeks of gestation and in the presence of preterm premature rupture of the membranes, placenta previa, fetal growth restriction, and postterm pregnancy.

Prenatal care and black-white fetal death disparity in the United States: heterogeneity by high-risk conditions.

OBJECTIVE: To determine the impact of prenatal care in the United States on the fetal death rate in the presence and absence of obstetric and medical high-risk conditions, and to explore the role of these high risk conditions in contributing to the black-white disparity. METHODS: This is a population-based, retrospective cohort study using the national perinatal mortality data for 1995-1997 assembled by the National Center for Health Statistics. Fetal death rate (per 1000 births) and adjusted relative risks were derived from multivariable logistic regression models. RESULTS: Of 10,560,077 singleton births, 29,469 (2.8 per 1000) resulted in fetal death. Fetal death rates were higher for blacks than whites in the presence (4.2 versus 2.4 per 1000) and absence (17.2 versus 2.5 per 1000) of prenatal care. Lack of prenatal care increased the (adjusted) relative risk for fetal death 2.9-fold in blacks and 3.4-fold in whites. Blacks were 3.3 times more likely to have no prenatal care compared with whites. Over 20% of all fetal deaths were associated with growth restriction and placental abruption, both in the presence and absence of prenatal care. Lack of prenatal care was associated with increased fetal death rates for both blacks and whites in the presence and absence of high-risk conditions. CONCLUSION: In the Unites States, strategies to increase prenatal care participation, especially among blacks, are expected to decrease fetal death rates.