Association between phthalate metabolites in human amniotic fluid and offspring birth size: a sub-study of the PERSIAN birth cohort.

As phthalate metabolites might cross the placenta, it is possible to find them in the amniotic fluid. This cross-sectional study aims to investigate the levels of phthalate metabolites in the amniotic fluid of a sample of Iranian women and its association with neonatal anthropometric measures. The other objective was to study the potential sources of maternal exposure to phthalates. This study was conducted from June 2019 to June 2021 in Isfahan, Iran. Pregnant women were recruited from their first trimester of pregnancy and followed up until their delivery. Amniotic fluid samples were collected from those who were assigned to have delivery by cesarean section. Overall, 158 samples of amniotic fluid were collected, of which 139 samples had sufficient volume and were free of blood. Data from 142 newborns were included in this study. Four phthalate metabolites were measured using gas chromatography-mass spectrometry (GC-MS). After extraction of phthalate metabolites, 4 phthalate metabolites including mono-butyl phthalate (MBP; normal: 0.08 ± 0.79; overweight: 0.20 ± 1.11; obese: 0.07 ± 1.07; p-value: 0.405), mono-benzyl phthalate (MBzP; normal: 7.54 ± 6.69; overweight: 7.48 ± 7.16; obese: 8.67 ± 12.75; p-value: 0.729), mono(2-ethyl-5-oxohexyl) phthalate (MEOHP; normal: 4.27 ± 6.36; overweight: 3.03 ± 8.44; obese: 3.53 ± 7.04; p-value: 0.245), and mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP; normal: 246.18 ± 189.80; overweight: 238.48 ± 200.23; obese: 287.65 ± 206.70; p-value: 0.723) were simultaneously detected in samples of maternal amniotic fluid. Our findings suggest that maternal exposure to phthalate metabolites is positively associated with in utero exposure of the developing fetus. The geometric means and medians of MBP, MBzP, MEOHP, and MEHHP of detected samples were 10.17 (9.52), 6.24 (3.47), 5.03 (11.72), and 174.79 (229.94) (µg/L), respectively. The median anthropometric measures of newborns were as follows: weight 3171.8 g, height 49.6 cm, head circumferences 34.9 cm, chest 33.3 cm, hip 31.5 cm, and arm circumferences 10.8 cm. There was no statistically significant association between phthalate metabolites concentration and newborn's anthropometric measures (p > 0.05). Future studies should focus on the collection of amniotic fluid at different trimesters and the corresponding maternal samples to better characterize the association and health impacts of these endocrine-disrupting chemicals during fetal development.

Association between parabens concentrations in human amniotic fluid and the offspring birth size: A Sub-study of the PERSIAN birth cohort.

OBJECTIVE: Parabens are extensively used, and cause widespread exposure of the general population including pregnant women and developing fetuses to these pollutants. In this study, we aimed to investigate the association between the maternal exposure of parabens to study their transfer passed through the placental barrier to amniotic fluid; the second objective was to determine the association of paraben concentration in the amniotic fluid with the offspring birth size. METHODS: This cross-sectional study was conducted from June 2019 to March 2021 in Isfahan, Iran. Samples of amniotic fluid were collected as set from 128 pregnant women at Cesarean section. The amniotic fluid concentrations of four parabens including methylparaben (MP), ethylparaben (EP), propylparaben (PP), and butylparaben (BP) were determined using gas chromatography tandem mass spectroscopy (GC-Mass). RESULTS: The pointed parabens were extracted from yielded clear supernatant using a dispersive liquid-liquid microextraction (DLLME) method. Four paraben derivatives including MP (normal: 0.68 ± 0.7; overweight: 1.40 ± 1.76; obese: 0.30 ± 0.26; p-value: 0.275), EP (normal: 0.14 ± 0.09; overweight: 0.72 ± 0.72; obese: 0.38 ± 0.05; p-value: 0.434), PP (normal: 0.05 ± 0.05; overweight: 0.06 ± 0.06; obese: 0.20 ± 0.17; p-value: 0.770), and BP (normal: 2.89 ± 1.80; overweight: 3.89 ± 6.48; obese: 5.80 ± 7.56; p-value: 0.341) were simultaneously detected in samples of maternal amniotic fluid using GC-MS. In 92.2% (n = 118) of pregnant women, the paraben derivatives (MP, EP, PP, BP) were detected. We found that considerable levels of MP, EP, PP, and BP existed in 22.6% (n = 29), 21.9% (n = 28), 29.7% (n = 38), and 85.2% (n = 109) of samples, respectively. In addition, the correlation between paraben concentrations in amniotic fluid and birth size was investigated. The results showed that an inverse significant association between MP and head circumference, chest, hip, and arm circumference. While a positive correlation between MP and height of newborn was observed. Similar correlations were observed for EP and weight, height, head circumference, chest, hip, and arm. CONCLUSION: The current study indicated that parabens have been detected in amniotic fluid samples and a strong/possible correlation between exposure of pregnant women to parabens and the birth size of newborns.