Associations among maternal soy intake, isoflavone levels in urine and blood samples, and maternal and umbilical hormone concentrations (Japan)

Abstract

AbsractObjectives In utero exposure to high levels of endogenous estrogens has been hypothesized to increase breast cancer risk in later life. A high intake of soy has been suggested to protect against breast cancer. We examined the hypothesis that maternal soy intake may be inversely associated with pregnancy hormone levels. Methods The concentrations of hormones (estradiol, estriol, and testosterone) and isoflavones (genistein, deidzein, and equol) were measured in the maternal urine and serum, and umbilical cord blood of 194 women during pregnancy and at delivery. Soy intake during pregnancy was assessed by 5-day diet records at approximately the 29th week of pregnancy. Results High correlations were observed for isoflavone levels between maternal samples and umbilical cord blood, indicating that isoflavone can be transferred from the maternal to the fetal compartment. None of the hormones measured in umbilical cord blood was significantly associated with any of the isoflavones measured. There were a few significant associations between maternal hormone levels and isoflavone measures during pregnancy, but their patterns of asso-

Genistein reduces the noxious effects of in utero bisphenol A exposure on the rat prostate gland at weaning and in adulthood

“…Plasma concentrations of 50e800 ng/ml have been found for GEN in adults who consume modest amounts of soy foods Setchell and Cole, 2003). Thus, fetus can be actively exposed to GEN by mothers who consume soy products during pregnancy since a high correlation has been observed for isoflavone serum levels between maternal and umbilical cord blood samples, indicating that GEN can be easily transferred to the fetus by placenta (Nagata et al, 2006). This isoflavone is often categorized as a phytoestrogen because of its ability to bind to estrogen receptors (ERs) but display weak estrogenic activity when compared to the estrogen (Vitale et al, 2013).…”

The Association between Nonylphenols and Sexual Hormones Levels among Pregnant Women: A Cohort Study in Taiwan

“…Multiple maternal factors including age, BMI, psychological status, dietary and nutriment intake, and medication use are all associated with hormone levels during gestation [53], [68], [69], [70]. Several epidemiological studies that focused on the effects of endocrine disrupting substances have shown that toxicants exposure such as polybromodiphenyl ethers and phthalates may affect hormone levels of pregnant women and neonates [71], [72], [73].…”

Relationship Between the Consumption of Soy and Its Derivatives During Critical Periods of Development and in Adulthood and Endocrine-Metabolic Disorders

“…The detection rates of phytoestrogens, genistein, daidzein and equol in the umbilical cord of the newborns were 100%, 80% and 35%, respectively [46]. Within this perspective, Nagata et al [47] also showed high correlations to isoflavone levels between samples of maternal and umbilical cord blood of 194 accompanied women during pregnancy [47].…”

“…In the context of this discussion, it is important to emphasize the ability of placental transfer of phytoestrogens from mother to fetus [46,47]. In this sense, 51 Japanese mothers were accompanied by the time of cesarean section, where we collected serum sample of the mother and the umbilical cord.…”