US EPA

3859034 

Journal Article 

Early prenatal phthalate exposure, sex steroid hormones, and birth outcomes 

Sathyanarayana, S; Butts, S; Wang, C; Barrett, E; Nguyen, R; Schwartz, SM; Haaland, W; Swan, SH; TIDES Team 

2017 

Yes 

Journal of Clinical Endocrinology and Metabolism
ISSN: 0021-972X
EISSN: 1945-7197 

102 

6 

1870-1878 

English 

28324030 

10.1210/jc.2016-3837 

WOS:000403139100011 

Context: Adequate sex steroid hormone concentrations are essential for normal fetal genital development in early pregnancy. Our previous study demonstrated an inverse relationship between third-trimester di-2-ethyl hexyl phthalate exposure and total testosterone (TT) concentrations. Here, we examine early-pregnancy phthalates, sex steroid hormone concentrations, and newborn reproductive outcomes.

Design: We examined associations between urinary phthalate metabolite concentrations in early pregnancy and serum free testosterone (FT), TT, estrone (E1), and estradiol (E2) in 591 woman/infant dyads in The Infant Development and Environment Study; we also examined relationships between hormones and newborn genital outcomes using multiple regression models with covariate adjustment.

Results: E1 and E2 concentrations were 15% to 30% higher in relation to 1-unit increases in log monoisobutyl phthalate (MiBP), mono-2-ethyl hexyl phthalate, and mono-2-ethyl-5-oxy-hexyl phthalate concentrations, and E2 was 15% higher in relation to increased log monobenzyl phthalate (MBzP). FT concentrations were 12% lower in relation to 1-unit increases in log mono(carboxynonyl) phthalate (MCNP) and mono-2-ethyl-5-carboxypentyl phthalate concentrations. Higher maternal FT was associated with a 25% lower prevalence of having a male genital abnormality at birth.

Conclusions: The positive relationships between MiBP, MBzP, and DEHP metabolites and E1/E2 are unique and suggest a positive estrogenic effect in early pregnancy. The inverse relationship between MCNP and DEHP metabolites and serum FT supports previous work examining phthalate/testosterone relationships later in pregnancy. Higher FT in relation to a 25% lower prevalence of male genital abnormalities confirms the importance of testosterone in early fetal development.