Background

Living near petrochemical industries has been reported to increase the risks of adverse birth outcomes, such as low birth weight and preterm delivery. However, evidence regarding the role of petrochemical exposure in pregnancy complications remains limited. This study evaluated the association between maternal proximity to petrochemical industrial parks (PIPs) during pregnancy and the occurrence of premature rupture of membranes (PROM).

Methods

We performed a population-based 1:3 case–control study by using the 2004–2014 Taiwanese Birth Certificate Database. Birth records reported as stillbirth or bearing congenital anomalies were excluded. Cases were newborns reported to have PROM, whereas controls were randomly sampled from those without any pregnancy complications by matching birth year and urbanization index of the residential township. The proximity to PIPs was evaluated by calculating the distance to the nearest PIP of the maternal residential township during pregnancy. Furthermore, petrochemical exposure opportunity, accounting for monthly prevailing wind direction, was quantified during the entire gestational period. We applied conditional logistic regression models to evaluate the associations.

Results

In total, 29371 PROM cases were reported during the study period, with a corresponding 88113 healthy controls sampled. The results revealed that living within a 3-km radius of PIPs during pregnancy would increase the risk of PROM (odds ratio [OR] = 1.76, 95% CI: 1.66–1.87). Furthermore, compared with the lowest exposed group, those with high petrochemical exposure opportunity had a significantly increased risk of PROM occurrence (OR = 1.69–1.75). The adverse effects remained robust in the subgroup analysis for both term- and preterm-PROM.

Conclusions

The results of the present work provide evidence that living near PIPs during pregnancy would increase the risk of PROM, and additional studies are warranted to confirm our findings.