Maternal occupational exposure to organic solvents and intrauterine growth in the ELFE cohort.

BACKGROUND: In developed countries, about 15% of women are occupationally exposed to solvents. Associations between this maternal occupational exposure and intrauterine fetal growth are inconsistent, but almost no existing study has investigated this relation by solvent family (oxygenated, petroleum, and chlorinated), although they may affect fetal growth differently. OBJECTIVES: To investigate the relations between maternal occupational solvent exposure, by solvent family, and the risk of neonates born small for gestational age (SGA), or with low birthweight, or with small head circumference (HC). METHODS: Among the 18,040 women enrolled in the Elfe rather than included in the Elfe birth cohort, we included 13,026 women who worked during pregnancy (72% of the cohort). Information about maternal occupations and industrial activities during pregnancy was collected by questionnaire at the maternity ward, and completed at 2-month when necessary. Using Matgéné job-exposure matrices, we assessed maternal occupational exposure to solvents. Logistic and multiple linear regressions were used to assess the association between maternal occupational solvent exposure and SGA status, birth weight, and HC. Analyses were conducted for exposure during pregnancy and also stratified by the trimester that pregnancy leave began. RESULTS: We observed a higher risk of SGA newborns among mothers occupationally exposed during pregnancy to petroleum solvents (ORadjusted = 1.26; 95%CI: 1.01 to 1.57). Among women working until the third trimester of pregnancy, we observed a higher risk of SGA newborns to those occupationally exposed to oxygenated solvents (ORadjusted = 1.75; 95%CI: 1.11 to 2.75), a significantly lower birthweight for infants of mothers exposed to petroleum solvents (ßadjusted = -47.37 g; -89.33 to -5.42), and a lower HC among newborns of those occupationally exposed to oxygenated solvents (ßadjusted = -0.28; -0.49 to -0.07) and to chlorinated solvents (ßadjusted = -0.29; -0.53 to -0.05). DISCUSSION: Our results suggest that maternal occupational solvent exposure may influence fetal growth, especially exposure into the third trimester of pregnancy.

Predictive value of head-perineum distance measured at the initiation of the active second stage of labor on the mode of delivery: A prospective cohort study.

OBJECTIVE: The objective was to assess the predictive value of head-perineum distance measured at the initiation of the active second stage of labor on the mode of delivery. MATERIAL AND METHODS: It was a prospective cohort study in an academic Hospital of Rennes, France, from July 1, 2020 to April 4, 2021 including 286 full-term parturients who gave birth to a newborn in cephalic presentation. A double-blind ultrasound measurement of the head-perineum distance was performed during the second phase of labor within five minutes after the onset of pushing efforts. The primary outcome was the mode of delivery (spontaneous vaginal delivery versus instrumental vaginal delivery or cesarean section). We performed a multivariate analysis to determine the predictive value of the head-perineum distance by adjusting on potential confounders. RESULTS: Overall, 199 patients delivered by spontaneous vaginal delivery, 80 by instrumental vaginal delivery, and seven by cesarean section. The head-perineum distance measured at the beginning of pushing efforts was predictive of the mode of delivery with a threshold at 44 mm (crude: sensitivity = 56.8 % and specificity = 79.3 %; adjusted: sensitivity = 79.4 % and specificity = 87.4 %). The risk of medical intervention was higher when the head-perineum distance is>44 mm with an adjusted OR of 2.78 [1.38; 5.76]. CONCLUSION: The head-perineum distance measured at the initiation of the active second stage of labor is predictive of the mode of delivery. Head-perineum distance below 44 mm predicts a vaginal delivery with the best diagnostic performance, and optimizes the time to start pushing efforts.