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Background: Phthalates are endocrine-disrupting chemicals linked to adverse pregnancy outcomes. Despite the sensitivity of female reproductive processes to oxidation-reduction reaction stress and endocrine disruption, evidence for the impact of women's phthalate exposure on the ability to establish and maintain pregnancy has been inconclusive. Objectives: We aimed to determine the relationship of preconception phthalate metabolite exposure with a) fecundability and pregnancy loss and b) markers of potential biological mechanisms, including reproductive hormones, inflammation, and oxidative stress. Methods: Data were collected from the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial, a preconception study following 1,228 women who were attempting pregnancy, for up to six menstrual cycles and throughout pregnancy if they became pregnant. Twenty phthalate metabolites were measured in a consecutive 3-d pooled urine sample at enrollment. Pregnancy was determined through urinary human chorionic gonadotropin (hCG) at the expected date of menses during each cycle and pregnancy loss as an observed loss following positive hCG. Highly sensitive C-reactive protein (hsCRP) and isoprostanes were measured at enrollment, and reproductive hormones were measured during the follicular phase, ovulation, and luteal phase. Discrete-time Cox proportional hazards models evaluated the relationship of phthalate metabolites with fecundability and weighted Poisson models with robust variance evaluated the risk of pregnancy loss. Results: An interquartile range (IQR) higher mono-(2-ethylhexyl) phthalate [fecundability odds ratio (FOR) =0.88; 95% confidence interval (CI): 0.78, 1.00], mono-butyl phthalate (FOR = 0.82; 95% CI: 0.70, 0.96), and mono-benzyl phthalate (FOR = 0.85; 95% CI: 0.74, 0.98) was associated with lower fecundability. No consistent associations were observed with pregnancy loss. Preconception phthalates were consistently associated with higher hsCRP and isoprostanes, as well as lower estradiol and higher follicle-stimulating hormone across the menstrual cycle. Discussion: Women's preconception exposure to phthalates was associated with lower fecundability, changes in reproductive hormones, and increased inflammation and oxidative stress. The pre- and periconception periods may represent sensitive windows for intervening to limit the reproductive toxicity of phthalate exposure. https://doi.org/10.1289/EHP12287, Introduction Phthalates are esters of 1,2-benzene dicarboxylic acid commonly used as plasticizers in polyvinyl chloride and as stabilizers in many personal care products. Common sources of phthalate exposure include inhalation [...]

Context: Diets high in plant-based protein have gained popularity due to increasing health concerns regarding consumption of animal products. Though links between intakes of certain protein-rich foods and reproductive disorders have been suggested, the relationship of overall animal and vegetable proteins with reproductive hormones among reproductive-aged women is unknown.Objective: To evaluate the associations between the intake of dietary protein with reproductive hormones and sporadic anovulation among reproductive-aged women.Design: A prospective cohort study, 2005-2007.Setting: University at Buffalo, western New York, United States.Participants: A total of 259 premenopausal women (18-44 years) without dietary restrictions.Main Outcome Measure(s): Serum reproductive hormones were determined up to 8 times per cycle for 2 cycles. Protein intake was assessed the day prior to hormone assessment at 4 visits/cycle using 24-hour recalls.Results: Overall, 84% of participants met the recommended dietary allowance for total protein set for reproductive-aged women. Neither total nor animal protein intake were associated with reproductive hormones or anovulation. However, vegetable protein intake in the lowest tertile was associated with lower luteal phase progesterone (-18.0%, 95% confidence interval [CI] -30.2, -3.6), higher follicle-stimulating hormone (3.8%, 95% CI 0.2, 7.6), and a higher risk of anovulation (risk ratio [RR] 2.53, 95% CI 1.21, 5.26), compared with the middle tertile. Nuts and seeds were the only protein-rich foods associated with an elevated risk of anovulation (RR 2.12, 95% CI 1.17, 3.85).Conclusions: Findings suggest that among women who meet the recommended dietary allowance for total protein, low intake of vegetable, but not animal, protein may disturb normal ovulatory function. [ABSTRACT FROM AUTHOR]