Does environmental crude oil pollution affect pregnancy outcomes? A comparison of two communities in Rivers State Nigeria

Background: Pregnant women interact with the environment and may be physiologically vulnerable in event of any chemical-related environmental catastrophe. This study examined the effect of environmental crude oil pollution on pregnancy outcomes in selected midwife-led Primary Health Care Centres in Rivers State, Nigeria. Methods: A retrospective-cohort design was applied using facility-based records. Pregnant residents of K-Dere (an oil polluted community) served as the exposed group, while pregnant residents of Iriebe served as the non-exposed group. A sample size of 338 systematically selected perinatal records was examined (169 records for each group). A data extraction sheet was used for data collection. Data were analyzed using Statistical Package for Social Sciences (SPSS) version 21. The level of significance was set at < 5%. Results: At 32 weeks of pregnancy, participants in the exposed group weighted significantly less than those in the non-exposed group (χ 2 = 22.34, df = 2, p = <0.001) and had a 60% higher risk of anaemia (64.5% vs. 40.2%, RR 1.6, 95%CI=1.29-1.99, p = 0.001). The exposed group had 108% higher risk of having preterm birth when compared to the non-exposed group (16% vs. 7.7%, RR 2.08, 95%CI=1.11-3.89; p=0.018). Conclusions: Pregnant women resident in crude oil polluted environments have increased risk of preterm birth, maternal anaemia and lower maternal body weight. The immediate clean-up of oil spills might improve pregnancy outcomes in crude oil polluted communities.