Birth outcomes of planned home births in Missouri: a population-based study

We evaluated the birth outcomes of planned home births. We conducted a retrospective cohort study using Missouri vital records from 1989 to 2005 to compare the risk of newborn seizure and intrapartum fetal death in planned home births attended by physicians/certified nurse midwives (CNMs) or non-CNMs with hospitals/birthing center births. The study sample included singleton pregnancies between 36 and 44 weeks of gestation without major congenital anomalies or breech presentation ( N?=?859,873). The adjusted odds ratio (aOR) of newborn seizures in planned home births attended by non-CNMs was 5.11 (95% confidence interval [CI]: 2.52, 10.37) compared with deliveries by physicians/CNMs in hospitals/birthing centers. For intrapartum fetal death, aORs were 11.24 (95% CI: 1.43, 88.29), and 20.33 (95% CI: 4.98, 83.07) in planned home births attended by non-CNMs and by physicians/CNMs, respectively, compared with births in hospitals/birthing centers. Planned home births are associated with increased likelihood of adverse birth outcomes.     

Neonatal Mortality for Primary Cesarean and Vaginal Births to Low‐Risk Women: Application of an “Intention‐to‐Treat” Model

ABSTRACT: Background: The percentage of United States births delivered by cesarean section continues to increase, even for women considered to be at low risk for the procedure. The purpose of this study was to use an “intention‐to‐treat” methodology, as recommended by a National Institutes of Health conference, to examine neonatal mortality risk by method of delivery for low‐risk women. Methods: Low‐risk births were singleton, term (37–41 weeks’ gestation), vertex births, with no reported medical risk factors or placenta previa and with no prior cesarean section. All U.S. live births and infant deaths for the 1999 to 2002 birth cohorts (8,026,415 births and 17,412 infant deaths) were examined. Using the intention‐to‐treat methodology, a “planned vaginal delivery” category was formed by combining vaginal births and cesareans with labor complications or procedures since the original intention in both cases was presumably a vaginal delivery. This group was compared with cesareans with no labor complications or procedures, which is the closest approximation to a “planned cesarean delivery” category possible, given data limitations. Multivariable logistic regression was used to model neonatal mortality as a function of delivery method, adjusting for sociodemographic and medical risk factors. Results: The unadjusted neonatal mortality rate for cesarean deliveries with no labor complications or procedures was 2.4 times that for planned vaginal deliveries. In the most conservative model, the adjusted odds ratio for neonatal mortality was 1.69 (95% CI 1.35–2.11) for cesareans with no labor complications or procedures, compared with planned vaginal deliveries. Conclusions: The finding that cesarean deliveries with no labor complications or procedures remained at a 69 percent higher risk of neonatal mortality than planned vaginal deliveries is important, given the rapid increase in the number of primary cesarean deliveries without a reported medical indication. (BIRTH 35:1 March 2008)     

Incidence of stillbirth and perinatal mortality and their associated factors among women delivering at Harare Maternity Hospital, Zimbabwe: a cross-sectional retrospective analysis

BACKGROUND: Death of an infant in utero or at birth has always been a devastating experience for the mother and of concern in clinical practice. Infant mortality remains a challenge in the care of pregnant women worldwide, but particularly for developing countries and the need to understand contributory factors is crucial for addressing appropriate perinatal health. METHODS: Using information available in obstetric records for all deliveries (17,072 births) at Harare Maternity Hospital, Zimbabwe, we conducted a cross-sectional retrospective analysis of a one-year data, (1997-1998) to assess demographic and obstetric risk factors for stillbirth and early neonatal death. We estimated risk of stillbirth and early neonatal death for each potential risk factor. RESULTS: The annual frequency of stillbirth was 56 per 1,000 total births. Women delivering stillbirths and early neonatal deaths were less likely to receive prenatal care (adjusted relative risk [RR] = 2.54; 95% confidence intervals [CI] 2.19-2.94 and RR = 2.52; 95% CI 1.63-3.91), which for combined stillbirths and early neonatal deaths increased with increasing gestational age (Hazard Ratio [HR] = 3.98, HR = 7.49 at 28 and 40 weeks of gestation, respectively). Rural residence was associated with risk of infant dying in utero, (RR = 1.33; 95% CI 1.12-1.59), and the risk of death increased with increasing gestational age (HR = 1.04, HR = 1.69, at 28 and 40 weeks of gestation, respectively). Older maternal age was associated with risk of death (HR = 1.50; 95% CI 1.21-1.84). Stillbirths were less likely to be delivered by Cesarean section (RR = 0.64; 95% CI 0.51-0.79), but more likely to be delivered as breech (RR = 4.65; 95% CI 3.88-5.57, as were early neonatal deaths (RR = 3.38; 95% CI 1.64-6.96). CONCLUSION: The frequency of stillbirth, especially macerated, is high, 27 per 1000 total births. Early prenatal care could help reduce perinatal death linking the woman to the health care system, increasing the probability that she would seek timely emergency care that would reduce the likelihood of death of her infant in utero. Improved quality of obstetric care during labor and delivery may help reduce the number of fresh stillbirths and early neonatal deaths.     

Short-term maternal and neonatal outcomes by mode of delivery. A case-controlled study

OBJECTIVE: Side-by-side comparisons of short-term maternal and neonatal outcomes for spontaneous vaginal delivery, instrumental vaginal delivery, planned caesarean section and caesarean section during labor in patients matched for clinical condition, age, and week of gestation are lacking. This case-controlled study was undertaken to evaluate short-term maternal and neonatal complications in a healthy population at term by mode of delivery. STUDY DESIGN: Four groups of healthy women, with antenatally normal singleton pregnancies at term, who underwent instrumental vaginal delivery (no. 201), spontaneous delivery (no. 402), planned caesarean section without labor (no. 402) and caesarean section in labor (no. 402) have been retrospectively selected. Outcome measures were maternal and neonatal short-term complications. Odds ratios (OR) and 95% confidence intervals (CI) were calculated. RESULTS: Maternal complications were mostly associated with forceps-assisted and vacuum-assisted instrumental deliveries (OR: 6.9; 95% CI: 2.9-16.4 and OR 3.0; 95% CI 1.1-8.8, respectively, versus spontaneous deliveries). No significant differences in overall complications were observed between spontaneous vaginal deliveries and caesarean sections, whether planned or in labor. By comparison with caesarean sections in labor, instrumental deliveries significantly increased the risk of complications (OR: 3.2; 95% CI: 1.6-6.5). Neonatal complications were also mostly correlated with forceps-assisted and vacuum-assisted instrumental deliveries (OR: 3.5; 95% CI: 1.9-6.7 and OR 3.8; 95% CI 2.0-7.4, respectively, versus spontaneous deliveries). By comparison with caesarean sections in labor, instrumental vaginal deliveries significantly increased the risk of complications (OR: 4.2; 95% CI: 2.4-7.4). CONCLUSIONS: In healthy women with antenatally normal singleton pregnancies at term, instrumental deliveries are associated with the highest rate of short-term maternal and neonatal complications.     

The effect of sequential use of vacuum and forceps for assisted vaginal delivery on neonatal and maternal outcomes

OBJECTIVE: To determine the risk of neonatal and maternal disease associated with the sequential use of vacuum and forceps compared with spontaneous vaginal delivery. STUDY DESIGN: Using Washington state birth certificate data linked to hospital discharge records, we compared 3741 vaginal deliveries by both vacuum and forceps, 3741 vacuum deliveries, and 3741 forceps deliveries to 11,223 spontaneous vaginal deliveries. RESULTS: Compared with spontaneous vaginal deliveries, deliveries by sequential use of vacuum and forceps had significantly higher rates of intracranial hemorrhage (relative risk [RR], 3.9; 95% confidence interval [CI], 1.5 to 10.1), brachial plexus (RR, 3.2; 95% CI, 1.6 to 6.4), facial nerve injury (RR, 13.3; 95% CI, 4.7 to 37.7), seizure (RR, 13.7; 95% CI, 2.1 to 88.0), depressed 5-minute Apgar score (RR, 3.0; 95% CI, 2.2 to 4.0), assisted ventilation (RR, 4.8; 95% CI, 2.1 to 11.0), fourth-degree (RR, 11.4; 95% CI, 6.4 to 20.1 among multiparous women) and other lacerations, hematoma (RR, 6.2; 95% CI, 2.1 to 18.1 among multiparous women), and postpartum hemorrhage (RR, 1.6; 95% CI, 1.3 to 2.0). The relative risk of sequential vacuum and forceps use was greater than the sum of the individual relative risks of each instrument for intracranial hemorrhage, facial nerve injury, seizure, hematoma, and perineal and vaginal lacerations. CONCLUSION: Sequential use of vacuum and forceps is associated with increased risk of both neonatal and maternal injury.     

Effect of labor on infant morbidity and mortality with preterm premature rupture of membranes: United States population-based study

OBJECTIVE: To evaluate whether labor, in the setting of premature rupture of membranes (PROM), affects infant morbidity and mortality rates. METHODS: We derived data for this population-based cohort study from the United States national linked birth infant death data sets, comprised of singleton live births delivered between 1995 and 1997. We included women (n = 34,594) who had preterm PROM more than 12 hours and delivered between 23 and 32 weeks' gestation. Birth records were used to determine whether delivery occurred with or without labor. Infants with birth weights below the tenth percentile for gestational age were classified as small for gestational age (SGA) on the basis of a nomogram of all singleton births in the United States between 1995 and 1997. Primary outcomes were early neonatal (0-6 days), late neonatal (7-27 days), postneonatal (28-365 days), and infant death (0-365 days). Secondary outcomes included respiratory distress syndrome (RDS), assisted ventilation, and neonatal seizures. Risks of infant mortality and morbidity from labor were examined separately for SGA and non-SGA infants. RESULTS: Overall rates were infant death 11.6%, RDS 15.1%, assisted ventilation 25.9%, and neonatal seizure 0.2%. Labor was associated with higher incidence of early neonatal death in SGA infants (adjusted relative risk [RR] 1.24, 95% confidence interval [CI] 1.11, 1.38) but had no effect on other outcomes. Among non-SGA infants, labor had no effect on infant death but was associated with higher rates of RDS (RR 1.15, 95% CI 1.08, 1.22) and assisted ventilation (RR 1.16, 95% CI 1.08, 1.24). CONCLUSION: Although labor was associated with a slightly higher mortality rate in SGA infants and slightly more respiratory morbidity in non-SGA infants, recommendations regarding clinical treatment should await future clinical trials.     

The impact of route of delivery and presentation on twin neonatal and infant mortality: a population-based study in the USA, 1995-97.

OBJECTIVE: We examined whether the route of delivery for near-term (> or = 34 weeks' gestation) twins, as candidates for vaginal delivery, affected neonatal and infant mortality rates. We further evaluated whether these mortality rates were modified by fetal presentation. METHODS: A population-based retrospective cohort study based on the matched multiple births data in the USA (1995-97) was performed. Analyses were restricted to non-malformed liveborn twins delivered at (> or = 34 weeks' gestation. Twins with breech-breech and breech-vertex presentations were excluded, since they are not candidates for vaginal delivery. Neonatal mortality rates (death within the first 27 days) and post-neonatal mortality rates (death between 28 and 365 days) per 1000 twin live births, by route of delivery and fetal presentation, were derived. The associations between neonatal mortality, post-neonatal mortality and the route of delivery for vertex-breech versus vertex-vertex presentations were expressed based on relative risks (RR) and 95% confidence intervals (CI) derived from logistic regression models based on the method of generalized estimating equations. RESULTS: Of the 177,622 twins analyzed, 87% (n = 154,531) presented as vertex-vertex. Fifty-five per cent (n = 97,692) of twins were both delivered vaginally, 41% (n = 72,825) were both delivered by Cesarean section and, of the remaining 4% (n = 7,105), the first twin was delivered vaginally and the second by Cesarean section. Twins with vertex-breech presentations delivered by Cesarean-cesarean sections, as well as those with vertex-vertex presentations delivered vaginally, had the lowest neonatal mortality rate (1.6 per 1000 live births). The highest neonatal mortality rate in the vertex-breech pairs occurred with vaginal-Cesarean deliveries (2.7 per 1000 live births). Among twins with vertex-vertex presentations, twins delivered via the vaginal-Cesarean route experienced the highest neonatal mortality (3.8 per 1000 live births). The RR for neonatal mortality in this group was 2.24 (95% CI 1.35, 3.72) compared with twins both delivered vaginally. CONCLUSION: Route of delivery and fetal presentation both confer an impact on twin infant mortality rates. Strategies to reduce discordant routes in complicated vaginal deliveries may lead to improved neonatal survival.     

Labor induction versus expectant management for postterm pregnancies: a systematic review with meta-analysis

OBJECTIVE: To compare routine labor induction with expectant management for patients who reach or exceed 41 weeks' gestation. DATA SOURCES: Computerized databases, references in published studies, and textbook chapters in all languages were used to identify randomized controlled trials (RCTs) evaluating induction and expectant management of labor for postterm pregnancies. METHODS OF STUDY SELECTION: We identified RCTs that compared induction and expectant management for uncomplicated, singleton, live pregnancies of at least 41 weeks' gestation and evaluated at least one of the following: perinatal mortality, mode of delivery, meconium-stained fluid, meconium aspiration syndrome, meconium below the cords, fetal heart rate (FHR) abnormalities during labor, cesarean deliveries for FHR abnormalities, abnormal Apgar scores, and neonatal intensive care unit (NICU) admissions. The primary outcomes assessed were cesarean delivery rate and perinatal mortality. TABULATION, INTEGRATION, AND RESULTS: Sixteen studies met inclusion criteria for this review. For each study with binary outcomes, an odds ratio (OR) with 95% confidence intervals (CIs) was calculated for selected outcomes. Estimates of ORs for dichotomous outcomes were calculated using fixed and random-effects models. Homogeneity was tested across the studies. Compared with women allocated to expectant management, those who underwent labor induction had lower cesarean delivery rates (20.1% versus 22.0%) (OR 0.88; 95% CI 0.78, 0.99). Although subjects whose labor was induced experienced a lower perinatal mortality rate (0.09% versus 0.33%) (OR 0.41; 95% CI 0.14, 1.18), this difference was not statistically significant. Similarly, no significant differences were noted for NICU admission rates, meconium aspiration, meconium below the cords, or abnormal Apgar scores. CONCLUSION: A policy of labor induction at 41 weeks' gestation for otherwise uncomplicated singleton pregnancies reduces cesarean delivery rates without compromising perinatal outcomes.     

The influence of obstetric intervention on trends in twin stillbirths: United States, 1989-99.

OBJECTIVE: Although twin stillbirth rates have declined substantially over the past two decades, the contribution of changes in obstetric interventions to reducing twin stillbirths has not been quantified. METHODS: We carried out a retrospective cohort study of twin live births and stillbirths in the United States between 1989 and 1999 (n=1,102,212). Changes in the rate of stillbirth (> or =22 weeks) before and after adjustment for changes in labor induction, Cesarean delivery and sociodemographic factors were estimated through ecological logistic regression analysis. This analysis was based on aggregating data by each state within the United States. RESULTS: Between 1989 and 1999, rates of labor induction and Cesarean delivery among twin live births increased by 138% (from 5.8% to 13.8%) and 15% (from 48.3% to 55.6%), respectively. These changes were accompanied by a 43% decline in the stillbirth rate between 1989 and 1999 (from 24.4 to 13.9 per 1000 fetuses at risk). After excluding births weighing < 500 g, rates of labor induction among twins at 22-27 weeks', 28-33 weeks' and > or =34 weeks' gestation increased by 95%, 131% and 127%, respectively, between 1989 and 1999. Cesarean delivery rates also increased by 55%, 29% and 2% in these same gestational age categories. The 48% (relative risk (RR) 0.52, 95% confidence interval (CI) 0.49-0.55) decline in stillbirth rate between 1989-91 and 1997-99 was reduced to a 25% (RR 0.75, 95% CI 0.72-0.79) decline after adjustment for changes in labor induction and Cesarean delivery. The decline in the rate of twin stillbirths was larger at later gestational ages (at > or =32 and > or =34 weeks) where the largest absolute increases in labor induction rates were observed. CONCLUSIONS: The use of Cesarean delivery and especially labor induction for twin pregnancies has increased substantially in the United States over the last decade and these changes have been associated with a large decline in the rate of stillbirth among twins.     

Optimal gestational age for twin delivery.

OBJECTIVE: We evaluated the timing of twin delivery associated with perinatal outcome in gestations of at least 36 completed weeks. STUDY DESIGN: This was a retrospective analysis of infant and maternal hospital records for a consecutive series of twin deliveries at New York Hospital-Cornell Medical Center. The inclusion criteria were delivery after 36 weeks' gestation during a 7-year period (1987 to 1993), without congenital anomalies or early fetal demise. Adverse perinatal outcomes were compared between deliveries before 38 weeks' gestational age and those at or after 38 weeks' gestation. RESULTS: Of 776 twin deliveries during the study period, 329 met the inclusion criteria. Adverse perinatal outcome was significantly higher among the twin pregnancies that delivered before 38 weeks' gestation compared with those that delivered at or after 38 weeks' gestation. Twin pregnancies that delivered between 36 and 37 weeks' gestation were 13 times more likely to require neonatal intensive care compared with those who delivered at or after 38 weeks' gestation (95% confidence interval 1.8 to 95.9; p < 0.001). CONCLUSION: In uncomplicated twin gestations, delivery at between 36 and 37 weeks' gestation was not associated with a reduction in neonatal complications compared with deliveries at or after 38 weeks' gestation.     

Cesarean delivery for twins: a systematic review and meta-analysis

OBJECTIVE: We undertook a systematic review and meta-analysis to determine whether a policy of planned cesarean section or vaginal delivery is better for twins. STUDY DESIGN: We searched MEDLINE and EMBASE from 1980 through May 2001 using combinations of the following terms: twin, delivery, cesarean section, vaginal birth, birth weight, and gestational age. Studies that compared planned cesarean section to planned vaginal birth for babies weighing at least 1500 g or reaching at least 32 weeks' gestation were included. We computed pooled odds ratios for perinatal or neonatal mortality, low 5-minute Apgar score, neonatal morbidity, and maternal morbidity. The infant was the unit of statistical analysis. Results were considered statistically significant if the 95% CI did not encompass 1.0. RESULTS: We retrieved 67 articles, 63 of which were excluded. Four studies with a total of 1932 infants were included in the analysis. A low 5-minute Apgar score occurred less frequently in twins delivered by planned cesarean section (odds ratio, 0.47; 95% CI, 0.26-0.88) principally because of a reduction among twins if twin A was in breech position (odds ratio, 0.33; 95% CI, 0.17-0.65). Twins delivered by planned cesarean section spent significantly longer in the hospital (mean difference, 4.01 days; 95% CI, 0.73-7.28 days). There were no significant differences in perinatal or neonatal mortality, neonatal morbidity, or maternal morbidity. CONCLUSION: Planned cesarean section may decrease the risk of a low 5-minute Apgar score, particularly if twin A is breech. Otherwise, there is no evidence to support planned cesarean section for twins.     

Risk factors and outcomes associated with a short umbilical cord

OBJECTIVE: To identify risk factors and outcomes associated with a short umbilical cord. METHODS: We conducted a population-based case-control study using linked Washington State birth certificate-hospital discharge data for singleton live births from 1987 to 1998 to assess the association between maternal, pregnancy, delivery, and infant characteristics and short umbilical cord. Cases (n = 3565) were infants diagnosed with a short umbilical cord. Controls (n = 14260) were randomly selected from among births without a diagnosis of short umbilical cord. RESULTS: Case mothers were less likely to be overweight (body mass index 25 or more, odds ratio [OR] 0.7; 95% confidence interval [CI] 0.6, 0.8) and more likely to be primiparous (OR 1.4; 95% CI 1.3, 1.6). Case infants were more likely to be female (OR 1.3; 95% CI 1.2, 1.4), have a congenital malformation (OR 1.6; 95% CI 1.4, 1.8), and be small for their gestational age (risk ratio [RR] 1.6; 95% CI 1.4, 1.9). A short cord was associated with increased risk for maternal labor and delivery complications, including retained placenta (RR 1.6; 95% CI 1.2, 2.3) and operative vaginal delivery (RR 1.4; 95% CI 1.3, 1.5). Adverse fetal and infant outcomes in cases included fetal distress (RR 1.8; 95% CI 1.6, 2.1) and death within the first year of life among term infants (RR 2.4; 95% CI 1.2, 4.6). CONCLUSION: Modifiable risk factors associated with the development of a short cord were not identified. Case mothers and infants are more likely to experience labor and delivery complications. Term case infants had a 2-fold increased risk of death, which suggests closer postpartum monitoring of these infants.     

Hospitalization and infant outcomes among women exposed and unexposed to tocolysis.

OBJECTIVE: To examine whether infants exposed to tocolytics are at increased risk for selected adverse clinical and hospitalization outcomes. STUDY DESIGN: We conducted a population-based cohort study of women with preterm labor, in Washington State from 1989 to 2001 (N=79,679), using linked hospitalization records. Relative risks for infant outcomes were estimated using multivariate logistic regression. RESULTS: Adjusted risk estimates for infants exposed to tocolysis were greater for respiratory distress (RR=1.5, 95% CI 1.4 to 1.6), intubation (RR=1.4, 95% CI 1.2 to 1.5), and bacterial infection (RR=1.6, 95% CI 1.4 to 1.8). Exposed infants were also more likely to have birth hospitalizations >2 days (RR=1.4, 95% CI 1.3 to 1.4), require transfer (RR=1.5, 95% CI 1.3 to 1.8), have increased hospital costs (RR=2.3, 95% CI 2.2 to 2.4), and require readmisssion within the first year of life (RR=1.2, 95% CI 1.1 to 1.3). CONCLUSION: Infants exposed to tocolytics appeared to have relatively poorer hospitalization and clinical outcomes; significant benefits were not observed.     

Extremely preterm vaginal breech delivery en caul

OBJECTIVE: To describe an alternative method of vaginal birth to the conventional assisted delivery for extremely preterm breech infants within intact amnions, and to compare the immediate neonatal outcomes with those delivered by cesarean. METHODS: Retrospective review of singleton breech deliveries under 26 weeks' gestation after spontaneous labor with intact membranes. Nine "en caul" vaginal births after tocolysis and six cesarean deliveries performed for the sole indication of preterm labor were identified between 1996 and 2001. RESULTS: The vaginal group's mean gestation and cervical dilatation on admission were 23(+6) weeks and 3.2 cm, respectively, and 24(+6) weeks and 2.8 cm in the cesarean group. Vaginal delivery occurred an average of 4 days after admission and 1 day for cesarean delivery. Mean time interval between the first corticosteroid injection and delivery was greater in the vaginal group (90 versus 22 hours). Failure to start or complete a steroid course was more likely in the operative group (67% versus 11%). Mean birth weights were comparable. Five-minute Apgar scores and cord pHs were 6 and 7.41, respectively, for vaginal births, and 5.5 and 7.32 after cesarean deliveries. Fifty-five percent of vaginally delivered infants had a 5-minute Apgar score less than 7, with 22% of the whole group dying during the first week of life. This compared with 66% and 50%, respectively, for cesarean infants. Of the survivors, average age at discharge was 121 days for both groups. CONCLUSION: Vaginal birth can be effected in extremely preterm breech pregnancies with intact membranes by adopting the "en caul" delivery method.     

Immediate neonatal outcomes after elective induction of labor

OBJECTIVE: To examine immediate neonatal outcomes associated with elective labor induction. STUDY DESIGN: Labor inductions occurring at > or = 38 weeks' gestation were examined during a 6-month period at 2 community hospitals. Medical records were reviewed by trained abstractors to determine the reason for induction (elective vs. medical) and maternal characteristics. The need for newborn resuscitation (1-minute Apgar score < 4) was the primary end point. Multiple logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Of the 364 inductions, 54.9% were elective. The odds of a 1-minute Apgar score being < or = 3 were significantly greater when labor was induced for elective reasons than for medical reasons (OR 5.5, 95% CI 1.1-27.9) or was spontaneous (OR 6.5, 95% CI 2.4-17.8), after controlling for mother's age, race and route of delivery. Elective induction was not associated with feal intolerance to labor, a low 5-minute Apgar score or need for admission to a special care nursery. CONCLUSION: An elective abortion induction is an independent risk factor for delivery of an infant requiring immediate attention.     

Previous cesarean delivery and risks of placenta previa and placental abruption

OBJECTIVE: To examine the association between cesarean delivery and previa and abruption in subsequent pregnancies. METHODS: A retrospective cohort study of first 2 (n = 156,475) and first 3 (n = 31,102) consecutive singleton pregnancies using the 1989-1997 Missouri longitudinally linked data were performed. Relative risk (RR) was used to quantify the associations between cesarean delivery and risks of previa and abruption in subsequent pregnancies, after adjusting for several confounders. RESULTS: Rates of previa and abruption were 4.4 (n = 694) and 7.9 (n = 1,243) per 1,000 births, respectively. The pregnancy after a cesarean delivery was associated with increased risk of previa (0.63%) compared with a vaginal delivery (0.38%, RR 1.5, 95% confidence interval [CI] 1.3-1.8). Cesarean delivery in the first and second births conferred a two-fold increased risk of previa in the third pregnancy (RR 2.0, 95% CI 1.3-3.0) compared with first two vaginal deliveries. Women with a cesarean first birth were more likely to have an abruption in the second pregnancy (0.95%) compared with women who had a vaginal first birth (0.74%, RR 1.3, 95% CI 1.2-1.5). Two consecutive cesarean deliveries were associated with a 30% increased risk of abruption in the third pregnancy (RR 1.3, 95% CI 1.0-1.8). A second pregnancy within a year after a cesarean delivery was associated with increased risks of previa (RR 1.7, 95% CI 0.9-3.1) and abruption (RR 1.5, 95% CI 1.1-2.3). CONCLUSION: A cesarean first birth is associated with increased risks of previa and abruption in the second pregnancy. There is a dose-response pattern in the risk of previa, with increasing number of prior cesarean deliveries. A short interpregnancy interval is associated with increased risks of previa and abruption. LEVEL OF EVIDENCE: II-2.     

Intrapartum transcervical amnioinfusion for meconium-stained amniotic fluid.

OBJECTIVE: To assess the rates of cesarean deliveries and perinatal outcome following intrapartum transcervical amnioinfusion in women with meconium-stained amniotic fluid (MSAF) in a setting with no electronic fetal monitoring or specialized neonatal care. MATERIALS AND METHODS: In this prospective comparative study with 150 women who were in labor and had MSAF, 50 of the women received a transcervical amnioinfusion and the remaining 100 women received standard care. The inclusion criteria were a pregnancy of at least 37 weeks' duration, a single live fetus in cephalic presentation, no major medical or obstetric complications, and no known fetal malformation. The amnioinfusion was performed with 1000 mL of normal saline solution through a red rubber catheter. RESULTS: Amnioinfusion was associated with a significant decrease in the incidence of low Apgar score (<7) at 1 min (12% vs. 47%; relative risk [RR], 0.26; 95% confidence interval [CI], 0.12-0.56); low Apgar score at 5 min (4% vs. 23%; RR, 0.17; 95% CI, 0.04-0.71); and meconium aspiration syndrome (4% vs. 18%; RR, 0.22; 95% CI, 0.05-0.92). There was also a trend towards a lesser incidence of cesarean deliveries (18% vs. 30%; RR, 0.6; 95% CI, 0.31-1.16) and perinatal deaths (4% vs. 13%; RR, 0.31; 95% CI, 0.07-1.31). The incidence of maternal hospital stays longer than 3 days was significantly lower in the amnioinfusion than in the control group (24% vs. 48%; RR, 0.5; 95% CI, 0.29-0.85). There were no major complications related to amnioinfusion. CONCLUSIONS: Intrapartum amnioinfusion for MSAF is a simple, safe, effective, and inexpensive procedure feasible in settings where intrapartum monitoring is limited. It is associated with improved perinatal outcome and could lower cesarean delivery rates in low-resource countries.     

Increased risk of adverse pregnancy outcome among Somali immigrants in Washington state

OBJECTIVE: The purpose of this study was to compare maternal and neonatal morbidity among Somali immigrants, US-born blacks and whites in Washington state. STUDY DESIGN: Washington state birth certificate data was linked to hospital discharge records comparing singleton deliveries among Somali immigrants with US-born blacks and whites between 1993 and 2001, in a 1:3 ratio. Outcomes were compared using unconditional multiple logistic regression models calculating odds ratios (ORs), and 95% confidence intervals (95% CIs). RESULTS: Five hundred seventy-nine pregnancies from Somali women were compared with 2384 and 2435 pregnancies from black and white women, respectively. Nulliparous Somali women were more likely to have a cesarean delivery than black or white control women, OR 1.6 (95% CI, 1.1-2.3) and 2.0 (95% CI, 1.4-2.8), respectively. Among all women who had cesarean deliveries, Somali women more commonly had cesarean deliveries associated with fetal distress and failed induction of labor. They were 9 times more likely than both control groups to deliver after 42 weeks gestation, and 4 times more likely than black women and 8 times more likely than white women to have oligohydramnios. Somali women were more likely to have gestational diabetes and significant perineal lacerations, and less likely to smoke. Newborns of Somali women were at increased risk for prolonged hospitalization, lower 5-minute Apgar scores, assisted ventilation, and meconium aspiration. CONCLUSION: Pregnancy outcomes should be evaluated within ethnically and culturally unique groups; Somali immigrants are a high-risk subpopulation.     

Cervical dimensions and risk of preterm birth: a prospective cohort study

OBJECTIVE: To examine the relation between cervical dilatation and length and the risk of spontaneous preterm birth, including its subtypes preterm labor and preterm premature rupture of membranes (PROM). METHODS: Cervical dimensions assessed by clinical examination were recorded prospectively at 24-29 weeks' gestation in 871 subjects with singleton pregnancies who were followed to delivery. Relative risks (RRs) of preterm birth, preterm labor, and preterm PROM were calculated for clinically distinguishable categories of cervical dilatation and length and for cervical score (length minus dilatation). Regression analysis was used to adjust for confounding. Time to delivery from baseline examination was summarized using survival analysis. RESULTS: There were 73 spontaneous preterm births (8.3%), 46 preterm labors and 27 cases of preterm PROM. All cervical measurements were associated with increased risks of preterm birth, with increasing abnormality more strongly predictive of risk. The adjusted RR for preterm birth with dilatation of at least 0.5 cm was 2.9 (95% confidence interval [CI] 1.2, 7.3); for length of 1.5 cm or less, the RR was 2.1 (95% CI 1.0, 4.5), and for cervical score less than 2.0, the RR was 2.8 (95% CI 1.4, 5.6). The association with cervical measurements was stronger for preterm PROM than for preterm labor, although precision was limited. These measurements had high specificity (93-99%) and low sensitivity (8-20%) for predicting preterm birth. CONCLUSION: In asymptomatic women at 24-29 weeks' gestation, greater cervical dilatation and shorter length were associated with increased risk of spontaneous preterm delivery, particularly preterm PROM.     

Effect of Maternal and Pregnancy Risk Factors on Early Neonatal Death in Planned Home Births Delivering at Home

Objective

The prevalence of home birth in the United States is increasing, although its safety is undetermined. The objective of this study was to investigate the effects of obstetrical risk factors on early neonatal death in planned home births delivering at home.