Mustieles V, et al. - Authors evaluated whether maternal and paternal preconception urinary bisphenol A (BPA) or bisphenol S (BPS) concentrations associated with offspring birth size. As per data, a correlation of maternal—but not paternal—preconception urinary BPA concentrations with lower birth size among couples seeking fertility evaluation was noted. For BPA effects on birth outcomes, the unexplored maternal preconception period may be a sensitive window.

Methods

• Experts included an ongoing prospective preconception cohort of women and men seeking fertility evaluation between 2005 and 2016 in a large fertility center in an academic hospital in Boston, MA, USA.
• They evaluated the relationship between maternal and paternal preconception, as well as maternal prenatal urinary BPA and BPS concentrations, and size at birth among 346 singletons from couples recruited in the Environment and Reproductive Health (EARTH) Study using multivariable linear regression.
• They abstratcted the infant birth weight and head circumference from delivery records.
• They estimated the mean preconception and prenatal exposures by averaging urinary ln-BPA and ln-BPS concentrations in multiple maternal and paternal urine samples collected before pregnancy, and maternal pregnancy samples collected in each trimester.

Results

• Findings suggested an inverse association between maternal preconception urinary BPA concentrations and birth weight and head circumference in adjusted models: each ln-unit increase was associated with a decrease in birth weight of 119 g (95% CI: -212, -27), and a head circumference decrease of 0.72 cm (95% CI: -1.3, -0.1).
• As per data, results were modestly attenuated by additional adjustment by gestational age or prenatal BPA exposure.
• Results demonstrated that women with higher prenatal BPA concentrations had infants with lower mean birth weight (-75 g, 95% CI: -153, 2) although this did not achieve statistical significance.
• They did not note an association of paternal preconception urinary BPA concentrations with either birth weight or head circumference.
• Researchers found that no consistent patterns emerged for BPS concentrations measured in either parent.