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CME Credit Offered
CME Credit Offered
Abstract Award
Abstract Award
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Poster Session 3

(857) Association Between Prenatal Exposure to Environmental Phthalates and Phenols with Adverse Pregnancy Outcomes

Friday, January 31, 2025
10:30 AM – 12:30 PM  

    Submitting Author and Presenting Author(s)

  • Misa Hayasaka, MD (she/her/hers)

    Department of Obstetrics and Gynecology, Macon and Joan Brock Virginia Health Sciences at ODU
    Norfolk, Virginia, United States

    • Coauthor(s)

  • George R. Saade, MD (he/him/his)

    Professor and Chair, Associate Dean for Women's Health Obstetrics and Gynecology
    Macon & Joan Brock Virginia Health Sciences Eastern Virginia Medical School at Old Dominion University
    Norfolk, Virginia, United States

  • Tetsuya Kawakita, MD, MS

    Associate Professor
    Macon & Joan Brock Virginia Health Sciences Eastern Virginia Medical School at Old Dominion University
    Norfolk, VA, United States

Objective: To evaluate the association between prenatal exposure to phthalates and phenols with adverse pregnancy outcomes.

Study Design: This prospective cohort study used data from the Environmental Influences on Child Health Outcomes (ECHO) consortium, which includes longitudinal data on over 30,000 pregnancies from 69 cohorts across the US. Participants were singleton pregnant individuals with data on urinary chemical concentrations at least one time during pregnancy and pregnancy outcomes. Urinary chemical measurements were performed separately by cohort. Individuals were classified into quartiles of various urinary chemical levels. Outcomes examined included preterm birth (PTB), small for gestational age (SGA), and gestational diabetes mellitus (GDM). Generalized estimating equations models with Poisson distribution and robust variance were used to estimate relative risks (RR) with 95% confidence intervals (95%CI) using the lowest quartile as the reference. All models were adjusted for maternal age, education, race and ethnicity, prepregnancy body mass index, marital status, and study cohorts.

Results: Among the 5,749 participants, 543 (9.4%) had PTB, 335 (5.8%) had SGA, and 401 (7.0%) had GDM. Table 1 presents the urinary levels of the chemicals assayed and the number of samples. Models showed that higher quartiles of phthalates and phenols were associated with an increased risk of PTB and SGA, whereas no significant associations were found for GDM (Table 2). The highest risk of PTB was noted with the 4th quartile of phthalic acid (RR 1.67; 95% CI 1.22-2.28) compared to the 1st quartile. The highest risk for SGA was observed with the 4th quartile of mono-isononyl phthalate (RR 2.37; 95%CI 1.57-3.58).

Conclusion: Pregnancy exposure to phthalates and phenols, ubiquitous environmental chemicals, could be preventable risk factors for PTB and SGA. Further study is needed to confirm these observations and identify the exposure sources.