Maternal Serum Concentrations of Per- and Polyfluoroalkyl Substances and Gestational Weight Gain: A Systematic Review and Meta-analysis

Abstract

Background: Humans are exposed everywhere to per-  and polyfluoroalkyl substances (PFASs) through water, food, and air. PFASs can alter cellular signals involved in weight homeostasis, particularly those related to peroxisome proliferator-activated receptors involved in abiogenesis. Some studies have shown a positive correlation between PFASs and gestational weight gain (GWG), but others have found no correlation. Therefore, the association between PFASs and weight gain in pregnancy was reviewed and meta-analyzed. Methods: This meta-analysis was approved by the PROSPERO team (CRD42023466602) and presented with a prospective protocol in accordance with the PRISMA guidelines. Google Scholar and databases such as the Cochrane Library, Web of Science, Scopus, Medline, Science Direct, and ProQuest were searched for English language findings from October 2023 to March 2024. Results: According to pooled regression coefficients, no significant relationship was observed between GWG values and the levels of all four PFASs, including perfluorooctanoic acid (PFOA) (β =0.01 [95% CI =  -0.38,  -0.36] I2 = 71.75%, P  =  0.03), perfluorooctane sulfonic acid (PFOS) (β =  -0.18 [95% CI =  -0.55,  -0.19] I2 = 36.65%, P  =  0.21), perfluorononanoic acid (PFNA) (β =0.07 [95% CI =  -0.27,  -0.41] I2 = 0.0%, P  =  0.74), and perfluorohexane-1-sulphonic acid (PFHxS), (β = -0.10 [95% CI = -0.34, -14] I2=18.54%, P = 0.293). The results of subgroup analysis based on pre-pregnancy body mass index (BMI) ≤25 showed only a significant relationship between PFNA plasma level and GWG (β =0.03 [95% CI =0.00,  -0.05] I2 = 64.96%, P  =  0.04). The findings from the subgroup analysis, which was conducted based on a pre-pregnancy body BMI of ≤25, revealed a significant correlation solely between PFNA plasma levels and GWG (β =0.03 [95% CI =0.00, -0.05] I2 = 64.96%, P = 0.04). Conclusions: Consequently, according to the estimated general regression coefficient, a doubling of the blood PFNA level is associated with an increase in the average GWG by 30 grams. In women with pre-pregnancy BMI >25 kg, no significant relationship between different levels of exposure and GWG was observed. No significant association was observed between major PFASs and weight gain during pregnancy, which may be because the exposure period (gestational length) was not sufficient. Especially as most of the influencing factors were adjusted in majority of the studies included in the meta-analysis. However, further cohort studies with larger sample sizes are needed.