Association of Maternal Medical Conditions and Unfavorable Birth Outcomes: Findings from the 1996–2003 Mississippi Linked Birth and Death Data

Placental abruption after amnioreduction for polyhydramnios caused by chorioangioma

Placental chorioangioma is the most common type of a benign placental tumour that occurs in 1% of pregnancies. A large chorioangioma is associated with adverse pregnancy outcomes. We present a case of placental abruption necessitating preterm delivery after multiple amnioreductions for polyhydramnios caused by a large chorioangioma. If antenatal diagnosis of a significant chorioangioma is made as the cause of polyhydramnios, caution should be taken when performing rapid amnioreductions.

A comparative analysis of prenatal care and fetal growth in eight South American countries

There has been little work that comprehensively compared the relationship between prenatal care and infant health across multiple countries using similar data sources and analytical models. Such comparative analyses are useful for understanding the background of differences in infant health between populations. We evaluated the association between prenatal care visits and fetal growth measured by birth weight (BW) in grams or low birth weight (<2500 grams; LBW) adjusted for gestational age in eight South American countries using similarly collected data across countries and the same analytical models. OLS and logistic regressions were estimated adjusting for a large set of relevant infant, maternal, and household characteristics and birth year and hospital fixed effects. Birth data were acquired from 140 hospitals that are part of the Latin American Collaborative Study of Congenital Malformations (ECLAMC) network. The analytical sample included 56,014 live-born infants (∼69% of total sample) with complete data born without congenital anomalies in the years 1996–2011 in Brazil, Argentina, Chile, Venezuela, Ecuador, Colombia, Bolivia, and Uruguay. Prenatal care visits were significantly (at p<.05) and positively associated with BW and negatively associated with LBW for all countries. The OLS coefficients ranged from 9 grams per visit in Bolivia to 36 grams in Uruguay. The association with LBW was strongest for Chile (OR = 0.87 per visit) and lowest for Argentina and Venezuela (OR = 0.95). The association decreased in the recent decade compared to earlier years. Our findings suggest that estimates of association between prenatal care and fetal growth are population-specific and may not be generalizable to other populations. Furthermore, as one of the indicators for a country’s healthcare system for maternal and child health, prenatal care is a highly variable indicator between countries in South America.

Preconception health of reproductive aged women of the Mississippi River delta

Optimal preconception health (PCH) may improve maternal and infant outcomes, priority issues in Mississippi (MS). Our study objective was to compare the PCH of women in the MS Delta to other regions. We analyzed Behavioral Risk Factor Surveillance System data from 2005, 2007, and 2009, and limited analyses to 171,612 non-pregnant black and white women 18-44 years of age. Region was defined as 14 MS Delta counties (MS Delta), remainder of MS (MS non-Delta), Delta states (LA, AR, TN), and non-Delta US states. We calculated adjusted prevalence ratios (aPR) to assess associations between region and 16 indicators of optimal PCH, controlling for demographic characteristics. Healthy PCH factors such as consuming ≥5 fruits and vegetables daily and normal body mass index (18.5 kg/m(2) to <25 kg/m(2)), respectively, were more prevalent in the MS non-Delta (aPR = 1.3; 95 % CI: 1.0,1.7 and aPR = 1.2; 95 % CI: 1.0,1.4), non-MS Delta (aPR = 1.5; 95 % CI: 1.2,2.0 and aPR = 1.3; 95 % CI: 1.1,1.5) and non-Delta states (aPR = 1.7; 95 % CI: 1.3,2.2 and aPR = 1.4; 95 % CI: 1.2,1.6) compared to the MS Delta. Physical activity levels were higher among non-Delta US states compared to the MS Delta (aPR = 1.3; 95 % CI: 1.1,1.4). Household income and race confounded the associations between region and PCH. Reproductive aged women in the MS Delta had poorer PCH, particularly for physical activity and nutrition, than women in other regions. MS Delta service providers and public health practitioners should consider implementing or enhancing lifestyle, nutrition, and physical activity interventions, with a special focus on reducing income-based and racial disparities.

Maternal racial origin and adverse pregnancy outcome: a cohort study

OBJECTIVE

To examine the association between maternal racial origin and a wide range of adverse pregnancy outcomes after adjustment for confounding factors in obstetric history and maternal characteristics.

METHODS

This was a retrospective study in women with singleton pregnancies attending their first routine hospital visit at 11 + 0 to 13 + 6 weeks of gestation. Data on maternal characteristics, and medical and obstetric history were collected and pregnancy outcomes ascertained. Regression analysis was performed to examine the association between racial origin and adverse pregnancy outcomes including pre-eclampsia (PE), gestational hypertension (GH), gestational diabetes mellitus (GDM), preterm delivery (PTD), small-for-gestational age (SGA), large-for-gestational age (LGA), miscarriage, stillbirth and elective and emergency Cesarean section (CS).

RESULTS

The study population included 76 158 singleton pregnancies with a live fetus at 11 + 0 to 13 + 6 weeks. In addition to maternal characteristics and obstetric history, Afro-Caribbean racial origin was associated with increased risk for miscarriage, stillbirth, PE, GH, spontaneous PTD, GDM, SGA and CS. In women of South Asian racial origin there was increased risk for PE, GDM, SGA and CS, and East Asian race contributed to the prediction of GDM and SGA.

CONCLUSION

Maternal racial origin should be combined with other maternal characteristics and obstetric history when calculating an individualized adjusted risk for adverse pregnancy outcome.

Maternal risk factors for low birth weight for term births in a developed region in China: a hospital-based study of 55,633 pregnancies

Low birth weight (LBW) is an important risk factor for neonatal and infant mortality and morbidity in adults.. However, no large scale study on the prevalence of LBW and related maternal risk factors in China has been published. To explore the effects of maternal factors on LBW for term birth in China, we conducted a hospital-based retrospective study of 55, 633 Chinese pregnancy cases between 2001 and 2008. Maternal sociodemographic data, history of infertility and contraceptive use were obtained. Their medical status and diseases during pre-pregnancy were examined by physical examination at the first antenatal care visit. Maternal medical status before childbirth and pregnancy outcomes, including body weight, infant gender, multiple pregnancy and congenital anomalies, were recorded. Univariate and multivariate logistic regression, and linear regression were used to investigate the relationship between maternal factors and term LBW. The general incidence of term LBW was 1.70% in the developed area of China. After preliminary analysis using the univariate model, low primary education, anemia, hypertensive disorders, placental previa, oligohydramnios and premature rupture of membrane were predicted as independent factors of term LBW in the multivariate model. Furthermore, the decrease in annual frquencies of these risk factors were major causes of gradual decline in the incidence of LBW (from 2.43% in 2001 to 1.21% in 2008). The study demonstrated that among maternal factors, primary education, anemia and hypertensive disorders could contribute to LBW for term birth even in the most developed area of China.

Maternal vitamin D receptor genetic variation contributes to infant birthweight among black mothers

Racial disparity in pregnancy outcomes is one of the most striking and poorly understood inequalities in American health. Genetic variability may be an important host factor influencing disparate birth outcomes between non-Hispanic black (NHB) and non-Hispanic white (NHW) women. Race-specific allelic frequencies in the vitamin D receptor (VDR) gene suggest its potential as a gene involved in health disparities. The Healthy Pregnancy, Healthy Baby Study is a prospective cohort of pregnant women aimed at identifying genetic, social, and environmental contributors to disparities in pregnancy outcomes in Durham, NC. VDR haplotype tagging single nucleotide polymorphisms (SNPs) were genotyped via Taqman assays for 615 women. Analysis of variance was used to examine the association between maternal genotype and infant birthweight. Eight of 38 SNPs examined showed nominal significance among NHB women, with one VDR SNP (rs7975232) surpassing the multiple testing significance threshold. rs7975232, an anonymous polymorphism, is part of a VDR gene haplotype associated with variation in mRNA stability. mRNA stability can affect the amount of protein produced, thus directly affecting vitamin D levels and calcium homeostasis. In contrast to NHBs, there was no association between any VDR SNP and birthweight for NHWs. Genetic factors contributing to disparities in birth outcomes are not expected to be explained entirely by variation in a single gene. Nevertheless, our results suggest that maternal VDR gene polymorphisms do influence birthweight with differential effects accruing across racial groups. Further research identifying the functionality of VDR gene polymorphisms in pregnant women will improve our understanding of the underlying mechanisms influencing birthweight.