Abstract
Background: Nonylphenols (NP) has been proven as an environmental hormone with estrogenic effects. The influence of human NP exposure is still unclear. The aim of this study is to explore the NP exposure effect on pregnancy outcomes. Methods: Urine samples of pregnant women in the first, second, and third trimester of gestation were collected respectively. They were asked to complete a structured questionnaire to collect the demographic and disease history information. Maternal urinary NP concentration was determined by high-performance liquid chromatography coupled with fluorescent detection. Birth outcomes were measured immediately by pediatrician after delivery. Results: The total number of participants was 201. Creatinine-adjusted urinary NP concentration were 7.27 ±10.08 ug/g, 6.43±8.78 ug/g, and 6.10±5.79 ug/g for the first, second, and third trimester, respectively (p >0.05). For 163 out of 201 pregnant women who were completely followed-up until delivery, above- median levels of urinary NP concentration in the second trimester had significantly decreased maternal weight gain (β=-1.39 kg, p=0.04) as well as neonatal birth length (β=-0.55 cm, p=0.02). The odds ratio of small gestational age on pregnant women with below-median levels of urinary NP concentration was 7.28 fold (95% CI=1.03-51.74). Conclusion: Maternal NP exposure levels in the second trimester are associated with a risk of decreased maternal weight gain and neonatal birth outcomes. This study indicates the 2nd trimester of pregnancy may be the most critical stage of protection from endocrine disruptors’ exposure.
