Association of self-reported personal care product use with blood glucose levels measured during pregnancy among women from a fertility clinic

Background: Personal care products (PCPs), known sources of endocrine disrupting chemicals (EDCs) such as phthalates and parabens, are widely used among women of reproductive age. EDCs have been linked to pregnancy complications such as gestational diabetes (GDM), and PCP use could represent a modifiable source of exposure in this sensitive time window. Yet, to our knowledge, no study has directly evaluated the association between pregnancy use of PCP and late pregnancy glucose levels, established risk factors for complications such as GDM. Methods: A total of 233 women from the Environment and Reproductive Health (EARTH) Study had data available on 1st and/or 2nd trimester PCP use, assessed through self-repotted use over the previous 24 h, and blood glucose levels after the glucose loading test (GLT), taken at late 2nd trimester. Associations between each individual PCP and total PCP with glucose levels were evaluated in multivariable adjusted linear regression models. Results: Both positive and negative differences in glucose levels were observed when comparing users vs. non-users of several PCPs including 2nd trimester use of deodorant (adjusted mean difference: 12.2 mg/dL, 95% CI: -0.6, 24.9); bar soap (6.9 mg/dL, 95% CI: -0.9, 14.7 mg/dL); and liquid soap (-13,3, 95% CI: -26.8, 0.1 mg/dL), and 1st trimester use of sunscreen (-14.6 mg/dL, 95% CI: -27.8, -1.5 mg/dL). Total number of PCPs used in the 2nd trimester was also associated with higher glucose levels, with the largest difference of 20 mg/dL when comparing individuals who used eight vs none PCPs (95% CI: 3-37). Conclusions: In a pregnancy cohort of women seelcing care at a fertility clinic, we found the use of several PCPs to be positively or negatively associated with glucose levels in the late second trimester, which may reflect increased risk of GDM and subsequent perinatal outcomes. These results sixengthen the role of product use as a potentially modifiable source of EDCs that may impact glucose levels. (C) 2019 Elsevier B.V. All rights reserved.