Fetal exposure to polybrominated diphenyl ethers and the risk of hypospadias: focus on the congeners involved.

BACKGROUND: Polybrominated diphenyl ethers (PBDEs) are widely used flame retardants, and their endocrine-disrupting properties have focused growing attention regarding their teratogenic potential. We have recently documented that mothers of children born with hypospadias had been exposed to statistically higher levels of PBDE during pregnancy than mothers of healthy controls. However, it is not known which congeners of PBDE are associated with this putative teratogenic effect. OBJECTIVES: To identify PBDE congeners associated with increased risk for hypospadias. STUDY METHODS: Hair samples from mothers were analyzed and compared between hypospadias cases and healthy controls for eight PBDE congeners using gas chromatography mass spectrometry (GC/MS). Polybrominated diphenyl ether levels were measured in the 0- to 3-cm segment closest to the skull of maternal hair as a proxy for in utero exposure of mothers who lived in the same environment for the duration of their pregnancy. RESULTS: Median maternal hair levels of five PBDE congeners (28, 47, 99, 153, and 154) and of total PBDE (∑PBDE) were significantly higher among mothers of infants with hypospadias (n = 152) than among controls (n = 64). Apparent greater differences in the lower brominated congeners, especially in BDE-47 and BDE-99, may be due to the fact that they had been used in larger amounts, and their persistence properties confer longer exposure. CONCLUSIONS: The majority of the lower brominated PBDE congeners measured in maternal hair exhibited higher PBDE body burden during pregnancy in mothers of infants who were born with hypospadias.

Pregnancy outcomes following first-trimester exposure to topical retinoids: a systematic review and meta-analysis.

Evaluation of human data regarding the outcomes of topical-retinoid-exposed pregnancies is important in terms of counselling pregnant women with inadvertent exposure. The objective of this study was thus to determine whether exposure to topical retinoids leads to an increase in the risk of adverse pregnancy outcomes. We carried out a search using the Medline, Embase, Web of Science and Cochrane Central Register of Controlled Trials databases from inception to 4 December 2014. The selection, review and quality assessment of the studies were carried out by two independent reviewers according to predetermined inclusion criteria. Odds ratios (ORs) were calculated by the random effects method. This meta-analysis, including a total of 654 pregnant women who were exposed to topical retinoids, and 1375 unexposed control pregnant women, did not detect significant increases in rates of major congenital malformations [OR 1·22, 95% confidence interval (CI) 0·65-2·29], spontaneous abortions (OR 1·02, 95% CI 0·64-1·63), stillbirth (OR 2·06, 95% CI 0·43-9·86), elective termination of pregnancy (OR 1·89, 95% CI 0·52-6·80), low birthweight (OR 1·01, 95% CI, 0·31-3·27) or prematurity (OR 0·69, 95% CI 0·39-1·23). No significant heterogeneity was detected among the studies for the evaluated outcomes. The present meta-analysis ruled out a major increase in the rates of major congenital malformations, spontaneous abortions, low birthweight and prematurity. This result may be used primarily in reassuring women who were inadvertently exposed to topical retinoids during their pregnancy. However, the statistical power is not adequate to justify the use of topical retinoids during pregnancy.