Stillbirth and early neonatal mortality in rural Central Africa

Objective

To develop a prospective perinatal registry that characterizes all deliveries, differentiates between stillbirths and early neonatal deaths (ENDs), and determines the ratio of fresh to macerated stillbirths in the northwest Democratic Republic of Congo.

Method

Birth outcomes were obtained from 4 rural health districts.

Results

A total of 8230 women consented, END rate was 32 deaths per 1000 live births, and stillbirth rate was 33 deaths per 1000 deliveries. The majority (75%) of ENDs and stillbirths occurred in neonates weighing 1500 g or more. Odds of stillbirth and END increased in mothers who were single or who did not receive prenatal care, and among premature, low birth weight, or male infants. The ratio of fresh to macerated stillbirths was 4:1.

Conclusion

Neonates weighing 1500 g or more at birth represent a group with a high likelihood of survival in remote areas, making them potentially amenable to targeted intervention packages. The ratio of fresh to macerated stillbirths was approximately 10-fold higher than expected, suggesting a more prominent role for improved intrapartum obstetric interventions.     

The project to understand and research preterm pregnancy outcomes and stillbirths in South Asia (PURPOSe): a protocol of a prospective,cohort study of causes of mortality among preterm births and stillbirths

Background

In South Asia, where most stillbirths and neonatal deaths occur, much remains unknown about the causes of these deaths. About one-third of neonatal deaths are attributed to prematurity, yet the specific conditions which cause these deaths are often unclear as is the etiology of stillbirths. In low-resource settings, most women are not routinely tested for infections and autopsy is rare.

Methods

This prospective, cohort study will be conducted in hospitals in Davengere, India and Karachi, Pakistan. All women who deliver either a stillbirth or a preterm birth at one of the hospitals will be eligible for enrollment. With consent, the participant and, when applicable, her offspring, will be followed to 28-days post-delivery. A series of research tests will be conducted to determine infection and presence of other conditions which may contribute to the death. In addition, all routine clinical investigations will be documented. For both stillbirths and preterm neonates who die ≤ 28 days, with consent, a standard autopsy as well as minimally invasive tissue sampling will be conducted. Finally, an expert panel will review all available data for stillbirths and neonatal deaths to determine the primary and contributing causes of death using pre-specified guidance.

Conclusion

This will be among the first studies to prospectively obtain detailed information on causes of stillbirth and preterm neonatal death in low-resource settings in Asia. Determining the primary causes of death will be important to inform strategies most likely to reduce the high mortality rates in South Asia.

Trial registration

Clinicaltrials.gov (NCT03438110) Clinical Trial Registry of India (CTRI/2018/03/012281).

     

Socio-economic and ethnic factors in stillbirth and neonatal mortality in the NE Thames Regional Health Authority (NETRHA) 1983

Summary. All stillbirths and neonatal deaths occurring in the North East Thames region were studied in 1983. This report describes the socio-economic and ethnic differences in that cohort. The stillbirth and neonatal mortality rates of babies born to fathers of social class V (16–8 per 1000 total births) was almost double that of social class I fathers (8–6 per 1000 total births). The most marked social class gradient was seen in the macerated stillbirth groups. Of particular concern was the extremely high stillbirth and neonatal mortality rate for women born in the Indian subcontinent. This was most evident in Pakistani women who had a stillbirth plus neonatal mortality rate of 17.3 per 1000 total births, almost twice that of the women born in the UK (9.0 per 1000 total births). Again, as with social class, macerated stillbirths appeared to contribute disproportionately to the excess mortality. Mortality rates were aggre gated into four birthweight specific groups. Asian women had higher mortality rates in the higher birthweight groups, whereas in the lower birthweight group their babies did slightly better. This study indicated that the special needs for working class and ethnic minority mothers within NE Thames were not being met, and the Regional Health Authority was strongly recommended to review services to these groups.     

The effects of maternal obesity on perinatal outcomes among those born small for gestational age*

Background: Maternal obesity has been associated with higher birth weight. Small for gestational age (SGA) neonates born to obese women may be associated with pathological growth with increased neonatal complications.

Methods: This was a retrospective cohort study of all non-anomalous singleton neonates born in Texas from 2006–2011. Analyses were limited to births between 34 and 42 weeks gestation with birth weight?≤10th percentile. Results were stratified by maternal pre-pregnancy BMI class. The risk for stillbirth, neonatal death, neonatal intensive care unit (NICU) admission and five?minute Apgar scores?<7 were estimated for each obesity class and compared to the normal weight group. Multivariable logistic regression analyses were performed to control for potential confounding variables.

Results: The rate of stillbirth was 1.4/1000 births for normal weight women, and 2.9/1000 among obese women (p?0.001, aOR: 1.83 [1.43, 2.34]). The rate of neonatal deaths among normal weight women was 4.3/1000 births, whereas among obese women it was 4.7/1000 (p?=?0.94, aOR: 1.10 [0.92, 1.30]). A dose-dependent relationship between maternal obesity and stillbirths was seen, but not for other neonatal outcomes.

Conclusion: Among SGA neonates, maternal pre-pregnancy obesity was associated with increased risks for stillbirth, NICU admission and low Apgar scores but not neonatal death.     

Birth weight discordancy and adverse perinatal outcomes among twin gestations in the United States: the effect of placental abruption

OBJECTIVE: We evaluated whether the relationship between birth weight discordancy of twins and stillbirth, neonatal deaths, and preterm births was modified by the presence of abruption. STUDY DESIGN: We used the 1995 to 1997 matched multiple birth file for United States twin births (n = 269287). Birth weight discordancy was defined as the ratio of the difference in birth weight of the heavier from the lighter twin to that of the heavier twin and was categorized as <5%, 5% to 9%, 10% to 14%, 15% to 19%, 20% to 29%, 30% to 39%, and >or=40%. We evaluated the risks of stillbirth (>or=20 weeks of gestation), neonatal deaths (within 28 days after birth), and preterm birth (< 32 weeks) in the presence and absence of abruption. Associations between birth weight discordancy and these perinatal outcomes were expressed as adjusted relative risks and were derived from multivariable logistic regression models, based on the method of generalized estimating equations. Risk of these outcomes were derived for each stratum of birth weight discordancy and abruption status, with the <5% birth weight discordancy, nonabruption status labeled as the reference group. All analyses were performed separately for same and different sex twins. RESULTS: A birth weight discordancy of >or=20% among same sex (adjusted relative risk, 1.2; 95% CI, 1.1, 1.4), and >or=40% among different sex twins (relative risk, 2.2; 95% CI, 1.7, 2.8) conferred increased risk for abruption. Among nonabruption births, a birth weight discordancy of >or=15% among same sex and >or=30% among different sex twins increased the risk of stillbirths, neonatal deaths, and preterm births. Among abruption births, however, the risks were increased even in the lowest birth weight discordancy category (<5%). The relative risks of stillbirths and neonatal deaths among abruption births were significantly higher for each birth weight discordancy group, both for same and different sex twins, compared with the reference group. The association between birth weight discordancy and preterm birth was not modified by either the presence or absence of abruption. CONCLUSION: Birth weight discordancy of >or=15% for same sex and >or=30% for different sex confer greatest risk of adverse perinatal outcomes in the absence of abruption. In the presence of placental abruption, these risks are further compounded. The results underscore the need for careful monitoring of twin pregnancies.     

Socio-economic and ethnic factors in stillbirth and neonatal mortality in the NE Thames Regional Health Authority (NETRHA) 1983

All stillbirths and neonatal deaths occurring in the North East Thames region were studied in 1983. This report describes the socio-economic and ethnic differences in that cohort. The stillbirth and neonatal mortality rates of babies born to fathers of social class V (16.8 per 1000 total births) was almost double that of social class I fathers (8.6 per 1000 total births). The most marked social class gradient was seen in the macerated stillbirth groups. Of particular concern was the extremely high stillbirth and neonatal mortality rate for women born in the Indian subcontinent. This was most evident in Pakistani women who had a stillbirth plus neonatal mortality rate of 17.3 per 1000 total births, almost twice that of the women born in the UK (9.0 per 1000 total births). Again, as with social class, macerated stillbirths appeared to contribute disproportionately to the excess mortality. Mortality rates were aggregated into four birthweight specific groups. Asian women had higher mortality rates in the higher birthweight groups, whereas in the lower birthweight group their babies did slightly better. This study indicated that the special needs for working class and ethnic minority mothers within NE Thames were not being met, and the Regional Health Authority was strongly recommended to review services to these groups.     

Determinants of perinatal mortality in Nigeria

Objective

To determine risk factors for perinatal mortality among hospital-based deliveries in Nigeria.

Methods

The WHO Global Maternal and Perinatal Health Survey was implemented in Nigeria as a first step in establishing a global system for monitoring maternal and perinatal health. Twenty-one health facilities with more than 1000 deliveries annually were selected by a stratified multistage cluster sampling strategy. Information was recorded on all women who delivered and their neonates within a 3-month period.

Results

Overall, there were 9208 deliveries, comprising 8526 live births, 369 fresh stillbirths, 282 macerated stillbirths, 70 early neonatal deaths, and 721 perinatal deaths. The stillbirth and perinatal mortality rates were, respectively, 71 and 78 per 1000 deliveries; the early neonatal death rate was 8 per 1000 live births. Approximately 10% of all newborns weighed less than 2500 g, and 12.3% were born at less than 37 weeks of gestation. Predictors of perinatal mortality were mother's age, lack of prenatal care, unbooked status, prematurity, and birth asphyxia.

Conclusion

The perinatal mortality rate remains unacceptably high in Nigeria. Fresh stillbirth accounted for most perinatal deaths. Interventions to improve the utilization and quality of prenatal care, in addition to the quality of intrapartum care, would considerably reduce perinatal death.     

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.     

Trends and determinants of stillbirth in developing countries: results from the Global Network’s Population-Based Birth Registry

Background

Stillbirth rates remain high, especially in low and middle-income countries, where rates are 25 per 1000, ten-fold higher than in high-income countries. The United Nations’ Every Newborn Action Plan has set a goal of 12 stillbirths per 1000 births by 2030 for all countries.

Methods

From a population-based pregnancy outcome registry, including data from 2010 to 2016 from two sites each in Africa (Zambia and Kenya) and India (Nagpur and Belagavi), as well as sites in Pakistan and Guatemala, we evaluated the stillbirth rates and rates of annual decline as well as risk factors for 427,111 births of which 12,181 were stillbirths.

Results

The mean stillbirth rates for the sites were 21.3 per 1000 births for Africa, 25.3 per 1000 births for India, 56.9 per 1000 births for Pakistan and 19.9 per 1000 births for Guatemala. From 2010 to 2016, across all sites, the mean stillbirth rate declined from 31.7 per 1000 births to 26.4 per 1000 births for an average annual decline of 3.0%. Risk factors for stillbirth were similar across the sites and included maternal age < 20 years and age > 35 years. Compared to parity 1–2, zero parity and parity > 3 were both associated with increased stillbirth risk and compared to women with any prenatal care, women with no prenatal care had significantly increased risk of stillbirth in all sites.

Conclusions

At the current rates of decline, stillbirth rates in these sites will not reach the Every Newborn Action Plan goal of 12 per 1000 births by 2030. More attention to the risk factors and treating the causes of stillbirths will be required to reach the Every Newborn Action Plan goal of stillbirth reduction.

Trial registration

NCT01073475.

     

Estimation of birth population-based perinatal-neonatal mortality and preterm rate in China from a regional survey in 2010

Abstract

Objective: To estimate birth population-based perinatal-neonatal mortality and preterm rate in China from a regional survey in 2010.

Study design: Data of total births in 2010 obtained from 151 level I–III hospitals in Huai’an, Jiangsu, were prospectively collected and analyzed.

Results: From 61?227 birth registries (including 60?986 live births and 241 stillbirths), we derive a birth rate of 11.3‰ (of 5.4 million regional population), a male-to-female ratio of 116:100 and valid data from 60?615 newborns. Mean birth weight (BW) was 3441?±?491?g with 13.6% macrosomia. Low BW was 2.8% (1691/60?372) with 8.83% mortality. Preterm rate was 3.72% (2239/60?264) with 7.61% mortality. Cesarean section rate was 52.9% (31?964/60?445), multiple pregnancy 1.8% (1088/60?567) and birth defects 6.7‰ (411/61?227). There were 97.4% healthy newborns and 2.2% (1298) requiring hospitalized after birth. The perinatal mortality was 7.7‰ (471/61?227, including 241 stillbirths, 230 early neonatal deaths). The neonatal mortality was 4.4‰ (269/60?986). The main causes of neonatal death were birth asphyxia (24.5%), respiratory diseases (21.5%), prematurity related organ dysfunction (18.5%) and congenital anomalies (7.7%), whereas incidence of congenital heart disease and respiratory distress syndrome was 8.6‰ and 6.1‰, respectively.

Conclusions: This regional birth population-based data file contains low perinatal-neonatal mortality rates, associated with low proportion of LBW and preterm births, and incidences of major neonatal disease, by which we estimate, in a nationwide perspective, in 16 million annual births, preterm births should be around 800?000, perinatal and neonatal mortality may be 128?000–144?000 and 80?000–96?000, respectively, along with 100?000 respiratory distress syndrome.     

Global report on preterm birth and stillbirth (1 of 7): definitions,description of the burden and opportunities to improve data

Introduction

This is the first of seven articles from a preterm birth and stillbirth report. Presented here is an overview of the burden, an assessment of the quality of current estimates, review of trends, and recommendations to improve data.

Preterm birth

Few countries have reliable national preterm birth prevalence data. Globally, an estimated 13 million babies are born before 37 completed weeks of gestation annually. Rates are generally highest in low- and middle-income countries, and increasing in some middle- and high-income countries, particularly the Americas. Preterm birth is the leading direct cause of neonatal death (27%); more than one million preterm newborns die annually. Preterm birth is also the dominant risk factor for neonatal mortality, particularly for deaths due to infections. Long-term impairment is an increasing issue.

Stillbirth

Stillbirths are currently not included in Millennium Development Goal tracking and remain invisible in global policies. For international comparisons, stillbirths include late fetal deaths weighing more than 1000g or occurring after 28 weeks gestation. Only about 2% of all stillbirths are counted through vital registration and global estimates are based on household surveys or modelling. Two global estimation exercises reached a similar estimate of around three million annually; 99% occur in low- and middle-income countries. One million stillbirths occur during birth. Global stillbirth cause-of-death estimates are impeded by multiple, complex classification systems.

Recommendations to improve data

(1) increase the capture and quality of pregnancy outcome data through household surveys, the main data source for countries with 75% of the global burden; (2) increase compliance with standard definitions of gestational age and stillbirth in routine data collection systems; (3) strengthen existing data collection mechanisms—especially vital registration and facility data—by instituting a standard death certificate for stillbirth and neonatal death linked to revised International Classification of Diseases coding; (4) validate a simple, standardized classification system for stillbirth cause-of-death; and (5) improve systems and tools to capture acute morbidity and long-term impairment outcomes following preterm birth.

Conclusion

Lack of adequate data hampers visibility, effective policies, and research. Immediate opportunities exist to improve data tracking and reduce the burden of preterm birth and stillbirth.

     

Qualitätssicherung und Senkung der antepartualen Mortalität

Quality control using birth surveys has been applied in Germany for 2 decades. Perinatal mortality fell in this period below 0.5% due to a dramatic reduction of sub partus and neonatal deaths. The stillbirth rate of 0.3–0.4% was not influenced up to 1995 in spite of the introduction of ultrasound screening and CTG monitoring during routine surveillance. Ultrasound is utilized with a frequency of >3 scans in some 50% of pregnancies, while more than 90% of pregnancies are monitored with antenatal CTG. Evaluation with multivariant analysis of 288,604 women during 1995–2000 in Hesse indicated a 30% reduction in the rate of stillbirth deliveries in high-risk pregnancies evaluated by ultrasound. CTG monitoring during prenatal care seemed to additionally reduce the number of stillbirths in low-risk pregnancies. Intensified antenatal surveillance implementing ultrasound and CTG screening achieved a reduction of stillbirths to 0.22 according to the Hessian data of 1998 and 1999, if calculated with a cut-off limit of 1000 g birth weight.     

Prevalence and outcome of higher order multiple pregnancies in Lagos,Nigeria

Abstract

Objective: To determine the prevalence and outcome of higher order multiple (HOM) pregnancies in Lagos, Nigeria.

Methods: The mode of delivery, gestational age, pregnancy and neonatal outcome of babies delivered from HOM pregnancies were reviewed retrospectively from the labor ward and theater registers, neonatal unit admission records and medical notes in a tertiary referral centre from April 2009 to March 2012.

Results: Twenty-two (15, 6 and 1 set of triplets, quadruplets and quintuplet, respectively) of 6521 pregnancies delivered during the period were HOM pregnancies giving a prevalence of 3.37/1000. All the 74 babies except 12 were delivered by cesarean section. There were 18 perinatal deaths giving a perinatal mortality rate of 243 per 1000. Overall mortality was significantly associated with no antenatal booking (21 versus 5, OR: 21.0, 95% CI: 2.1–72.3, p?=?0.000), gestational age ≤30 weeks (21 versus 5, OR: 46.2, 95% CI: 11.2–189.9, p?=?0.000) and birth weight <1000?g for live births (p?=?0.000). Mode of delivery and number of fetuses >3 were however not significantly associated with mortality.

Conclusion: Reduction of early preterm births by proper antenatal care and close feto-maternal monitoring of HOM pregnancies will significantly reduce the resultant immediate poor outcomes for these pregnancies and their newborns.     

The Maternal and Newborn Health Registry Study of the Global Network for Women's and Children's Health Research

ObjectiveTo implement a vital statistics registry system to register pregnant women and document birth outcomes in the Global Network for Women's and Children's Health Research sites in Asia, Africa, and Latin America.MethodsThe Global Network sites began a prospective population-based pregnancy registry to identify all pregnant women and record pregnancy outcomes up to 42 days post-delivery in more than 100 defined low-resource geographic areas (clusters). Pregnant women were registered during pregnancy, with 42-day maternal and neonatal follow-up recorded—including care received during the pregnancy and postpartum periods. Recorded outcomes included stillbirth, neonatal mortality, and maternal mortality rates.ResultsIn 2010, 72 848 pregnant women were enrolled and 6-week follow-up was obtained for 97.8%. Across sites, 40.7%, 24.8%, and 34.5% of births occurred in a hospital, health center, and home setting, respectively. The mean neonatal mortality rate was 23 per 1000 live births, ranging from 8.2 to 48.5 per 1000 live births. The mean stillbirth rate ranged from 13.7 to 54.4 per 1000 births.ConclusionThe registry is an ongoing study to assess the impact of interventions and trends regarding pregnancy outcomes and measures of care to inform public health.ClinicalTrial.gov Trial Registration: NCT01073475     

Cytogenetic Studies in Perinatal Death

Following tissue culture cytogenetic studies were performed on tissue obtained from 136 fetuses who died in the perinatal period (98 stillbirths and 38 neonatal deaths). The gestational age of the stillbirths was evenly distributed between 20 and 40 weeks (1 was 42 weeks) while 74% of the neonatal deaths were term babies. Analyzable metaphases were obtained in 45 stillbirth specimens (46%) and 32 neonatal specimens (84%). Abnormal karyotypes were identified in 7 of the stillbirths (15.5%) and 8 of the neonatal deaths (25%) and all these were from babies with congenital anomalies identified at autopsy. Time delays were crucial to the success of culture from stillbirths, but specimens obtained from neonatal deaths could be grown successfully up to 3 days after death. Generally the placenta was more viable than other tissues, including skin, cartilage and muscle. Whereas growth was obtained in 69% of fresh unexplained stillbirths, no tissue from the macerated stillbirths grew. This is a group which may have a high abnormality rate. We recommend that if fetal assessment during pregnancy suggests a compromised fetus and there are no maternal factors to account for this, an amniocentesis be performed.     

Perinatal mortality in first- and second-born twins in the United States

OBJECTIVE: To evaluate the prevailing mortality paradox that second-born twins are at higher risk of perinatal mortality than first-born twins. METHODS: We used the 1995-1997 United States "matched multiple birth" data files assembled by the National Center for Health Statistics, for analysis of risk of perinatal mortality in first- and second-born twins (293788 fetuses). Perinatal mortality was defined to include stillbirths after 20 weeks of gestation and neonatal deaths (deaths within the first 28 days). Gestational age-specific risk of perinatal mortality (per 1000 total births), stillbirth (per 1000 total births), and neonatal mortality (per 1000 livebirths) by order of twin birth were based on the fetuses-at-risk approach. Associations between order of birth and mortality indices were evaluated by fitting multivariable logistic regression models based on the method of generalized estimating equations. These models were adjusted for several potential confounding factors. RESULTS: Perinatal mortality was 37% higher in second-born (26.1 per 1000 total births) than in first-born (20.3 per 1000 total births) twins (adjusted relative risk [RR] 1.37; 95% confidence interval [CI] 1.32, 1.42). The increased risk of perinatal mortality in second-born twins was chiefly driven by a 2.46-fold (95% CI 2.29, 2.63) increase in the number of stillbirths. However, the risk of neonatal mortality was very similar between first- and second-born twins (RR 0.99, 95% CI 0.95, 1.04). CONCLUSIONS: The increased risk of perinatal death in second-born twins is driven chiefly by increased rates of stillborn second twins. Thus, the increased mortality in second-born over first-born twins probably is an artifact of mortality comparisons.     

Influence of time of delivery on risk of adverse neonatal outcome in different size of delivery units: a retrospective cohort study in Finland

Purpose: To evaluate the impact of time of birth on adverse neonatal outcome in singleton term hospital births.

Materials and methods: Medical Birth Register Data in Finland from 2005 to 2009. Study population was all hospital births (n?=?263,901), excluding multiple pregnancies, preterm births <37 weeks, major congenital anomalies or birth defects, and antepartum stillbirths. Main outcome measures were either 1-minute Apgar score 0–3, 5-minute Apgar score 0–6, or umbilical artery pH <7.00, and intrapartum and early neonatal mortality. We calculated risk ratios (ARRs) adjusted for maternal age and parity, and 95% confidence intervals (CIs) to indicate the probability of adverse neonatal outcome outside of office hours in normal vaginal delivery, in vaginal breech delivery, in instrumental vaginal delivery, and in elective and nonelective cesarean sections. We analyzed different size-categories of maternity hospitals and different on-call arrangements.

Results: Instrumental vaginal delivery had increased risk for mortality (ARR 3.31, 95%CI; 1.01–10.82) outside office hours. Regardless of hospital volume and on-call arrangement, the risk for low Apgar score or low umbilical artery pH was higher outside office hours (ARR 1.23, 95%CI; 1.15–1.30). Intrapartum and early neonatal mortality increased only in large, nonuniversity hospitals outside office hours (ARR 1.51, 95%CI; 1.07–2.14).

Conclusions: Compared to office hours, babies born outside office hours are in higher risk for adverse outcome. Demonstration of more detailed circadian effects on adverse neonatal outcomes in different subgroups requires larger data.     

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 (???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 ??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 ??32 and ??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.     

Pregnancies in young adolescent mothers: a population-based study on 37 million births

ObjectivesPregnancy in young adolescents is often understudied. The objective of our study was to evaluate the effect of young maternal age on adverse obstetrical and neonatal outcomes.MethodsWe conducted a population-based cohort study using the Center for Disease Control and Prevention’s Linked Birth-Infant Death and Fetal Death data on all births in the US between 1995 and 2004. We excluded all births of gestational age under 24 weeks and those with reported congenital malformations or chromosomal abnormalities. Maternal age was obtained from the birth certificate and relative risks estimating its effect on obstetrical and neonatal outcomes were computed using unconditional logistic regression analysis.Results37,504,230 births met study criteria of which 300,627 were in women aged <15 years with decreasing rates from 11/1,000 to 6/1,000 over a 10-year period. As compared to women 15 years and older, women <15 were more likely to be black and Hispanic, less likely to have adequate prenatal care, and more likely to not have had any prenatal care. In adjusted analysis, births to women <15 were more likely to be IUGR, born under 28, 32, and 37 weeks’ gestation and to result in stillbirths and infant deaths. Prenatal care was protective against infant deaths in women < 15 years of age.ConclusionAlthough public health initiatives have been successful in decreasing rates of young adolescent pregnancies, these remain high risk pregnancies that may benefit from centers capable of ensuring adequate prenatal care.