Prenatal exposures to persistent organic pollutants and menstrual characteristics in girls at age 12 in the French PELAGIE cohort

Few studies have evaluated the impact of prenatal exposure to persistent organic pollutants (POPs) on menstruation characteristics. Therefore, the aim of our study was to investigate the associations between cord blood concentrations of POPs and menstruation characteristics including menarche status, menstrual regularity, pain and duration in girls at age 12. We used data from the French PELAGIE mother-child cohort follow-up at 12 years old which included a questionnaire on menstruation characteristics. POP concentrations of 14 organochlorine pesticides (OCPs), 17 polychlorinated biphenyls (PCBs), 5 polybrominated diphenyl ethers (PBDEs), and 9 per-polyfluoroalkyl substances (PFAS) were measured on cord blood sampled at birth. We used multivariate logistic regression and Poisson regression to study the relation between prenatal POPs and menarche status, regularity of menstruations, menstruation duration, and severe pain in the lower abdomen or cramps (N = 296). The effect of mixtures of POPs on these outcomes were assessed using quantile g-computation. The majority of POPs were associated with a non-statistically significant increased risk of menarche at 12 years old, especially for the PCB mixture (OR = 1.29, 95 % CI [0.99; 1.68]). We also observed a statistically significant association between the second tercile of dieldrin (OR = 2.91, 95 % CI [1.13; 7.82]) and PFNA (OR = 3.13, 95 % CI [1.01; 10.43]) and severe pain in the lower abdomen or cramps, and a statistically significant association between the second tercile of hexachlorobenzene and menstruation duration (% change = 25.6 %, 95 % CI [1.2; 56.6]). For others POPs and other menstrual characteristics we did not observe any associations. Further longitudinal studies are needed to confirm these results, possibly through combined analyses of several mother-child cohorts to increase study power.