Maternal Smoking, GSTM1 and GSTT1 Polymorphism and Susceptibility to Adverse Pregnancy Outcomes

The objective of the study was to investigate the association between maternal smoking, GSTM1, GSTT1 polymorphism, low birth weight (LBW, < 2,500 g) and intra-uterine growth restriction (IUGR, < 2,500 g and gestation ≥ 37 weeks) risk. Within a prospective cohort study in Kaunas (Lithuania), a nested case-control study on LBW and IUGR occurrence among 646 women with genotyping of GSTT1 and GSTM1 polymorphisms who delivered live singletons was conducted. Multivariate logistic regression analysis was used to study the association of maternal smoking and polymorphism in two genes metabolizing xenobiotics. Without consideration of genotype, light-smoking (mean 4.8 cigarettes/day) during pregnancy was associated with a small increase in LBW risk, adjusted OR 1.21; 95% CI 0.44 – 3.31. The corresponding odds for IUGR risk was 1.57; 95% CI 0.45 – 5.55. The findings suggested the greater LBW risk among light-smoking mothers with the GSTM1-null genotype (OR 1.91; 95% CI 0.43 – 8.47) compared to those with GSTM1-present genotype (OR 1.11; 95% CI 0.26 – 4.47). When both GSTM1 and GSTT1 genotypes were considered, the synergistic effect was found among smoking mothers: GSTT1-present and GSTM1-null genotype OR for LBW was 3.31; 95% CI 0.60–18.4 and that for IUGR was 2.47; 95% CI 0.31 – 13.1. However there was no statistically significant interaction between maternal smoking, GSTT1- present and GSTM1-null genotypes for LBW (OR 1.45; 95% CI 0.22 – 10.1, p = 0.66) and for IUGR (OR 1.10; 95% CI 0.10 – 12.6, p = 0.93). The results of this study suggested that smoking, even at a low-level, ought to be considered a potential risk factor for adverse birth outcomes and that genetic polymorphism may contribute to individual variation in tobacco smoke response

Maternal Race, Demography, and Health Care Disparities Impact Risk for Intraventricular Hemorrhage in Preterm Neonates

OBJECTIVE: To determine whether risk factors associated with Grade (Gr) 2–4 intraventricular hemorrhage (IVH) differs between African ancestry and white subjects. STUDY DESIGN: Inborn, appropriate for gestational age (GA) infants with birth weights (BW) 500–1250 grams and exposed to >1 dose of antenatal steroids were enrolled in 24 neonatal intensive care units. Cases had Gr 2–4 IVH and controls matched for site, race and BW range had 2 normal ultrasounds read centrally. Multivariate logistic regression modeling identified factors associated with IVH across African ancestry and white race. RESULTS: Subjects included 579 African ancestry or white race infants with Gr 2–4 IVH and 532 controls. Mothers of African ancestry children were less educated, and white case mothers were more likely to have > 1 prenatal visit and have a multiple gestation (P ≤.01 for all). Increasing GA (P =.01), preeclampsia (P < .001), complete antenatal steroid exposure (P = .02), cesarean delivery (P < .001) and white race (P = .01) were associated with decreased risk for IVH. Chorioamnionitis (P = .01), Apgar< 3 at 5 min (P < .004), surfactant (P < .001) and high frequency ventilation (P < .001) were associated with increased risk for IVH. Among African ancestry infants, having >1 prenatal visit was associated with decreased risk (P = .02). Among white infants, multiple gestation was associated with increased risk (P < .001) and higher maternal education with decreased IVH risk (P < .05). CONCLUSION: Risk for IVH differs between African ancestry and white infants and may be attributable to both race and health care disparities