Perfluoroalkyl Substances During Pregnancy and Validated Preeclampsia Among Nulliparous Women in the Norwegian Mother and Child Cohort Study

Abstract

Perfluoroalkyl substances (PFAS) are persistent and ubiquitous environmental contaminants, and human exposure to these substances may be related to preeclampsia, a common pregnancy complication. Previous studies have found serum concentrations of PFAS to be positively associated with pregnancy-induced hypertension and preeclampsia in a population with high levels of exposure to perfluorooctanoate. Whether this association exists among pregnant women with background levels of PFAS exposure is unknown. Using data from the Norwegian Mother and Child Cohort Study conducted by the Norwegian Institute of Public Health, we carried out a study of nulliparous pregnant women enrolled in 2003-2007 (466 cases, 510 noncases) to estimate associations between PFAS concentrations and an independently validated diagnosis of preeclampsia. We measured levels of 9 PFAS in maternal plasma extracted midpregnancy; statistical analyses were restricted to 7 PFAS that were quantifiable in more than 50% of samples. In proportional hazards models adjusted for maternal age, prepregnancy body mass index (weight (kg)/height (m)(2)), educational level, and smoking status, we observed no strongly positive associations between PFAS levels and preeclampsia. We found an inverse association between preeclampsia and the highest quartile of perfluoroundecanoic acid concentration relative to the lowest quartile (hazard ratio = 0.55, 95% confidence interval: 0.38, 0.81). Overall, our findings do not support an increased risk of preeclampsia among nulliparous Norwegian women with background levels of PFAS exposure.

Reliability of perfluoroalkyl substances in plasma of 100 women in two consecutive pregnancies

“…Maternal plasma concentrations of PFOS, PFOA and PFHxS were lower than in previous studies with women recruited in the MoBa study and lower than in the NHANES 2003-2004 survey (Starling et al, 2014a; Starling et al, 2014b; Woodruff et al, 2011). On the other hand, maternal PFASs were comparable to another Norwegian study with a similar blood collection period (Berg et al, 2014).…”

“…The laboratory technicians were blinded to their identity, and the QA/QC samples were indistinguishable from the plasma samples of the study participants. The inter-assay coefficient of variation was 11.4 for PFOS, 8.6 for PFOA, 14.6 for PFHxS, 13.3 for PFNA, 22.2 for PFUnDA, and 27.0 for PFDA (Starling et al, 2014a). …”

Maternal Plasma Concentrations of Per- and Polyfluoroalkyl Substances and Breastfeeding Duration in the Norwegian Mother and Child Cohort

“…Participant data were linked with data from the Medical Birth Registry of Norway (MBRN). This dataset was produced by combining two prior studies using MoBa participants; these studies examined the relationship between PFASs plasma concentrations and subfecundity and preeclampsia (20, 21). Information on inclusion criteria can be found in the source studies (20, 21).…”

Per- and polyfluorinated substances (PFASs): Environmental challenges

“…An association of higher maternal PFOA and PFOS plasma levels with longer times to pregnancy (subfecundity) was reported [320], but not confirmed [321], or was found with parous, but not nulliparous women [322]. No increased risk of preeclampsia was found among nulliparous women with background levels of various PFAAs [323]. PFOS has been associated with reduced testosterone [324].…”