Inflammation and Ovarian Function in Reproductive-Aged Women.

Introduction: Inflammation is a marker of immune activation. Inflammation may have an effect on both ovarian function and luteal function, both essential to pregnancy. High inflammation may also signal dysregulated processes within the ovary, which could be in part measured through Anti-Müllerian hormone, follicle-stimulating hormone, and inhibin B levels.

Objective: To determine the relationship between inflammation, measured by C-reactive protein, and three biomarkers of ovarian function during the early follicular phase: Anti-Müllerian hormone, follicle-stimulating hormone, and inhibin B.

Methods: Secondary cross-sectional analysis of data and serum obtained in Time to Conceive, a prospective cohort study sample of 843 women attempting pregnancy in central North Carolina from 2008 to 2016. Participants were aged 30 and 44 years, had no history of infertility, endometriosis, or polycystic ovarian syndrome, and were not currently breastfeeding. Serum samples were obtained on days 2, 3, or 4 of the menstrual cycle. C-reactive protein (natural-log transformed), Anti-Müllerian hormone (natural-log transformed), follicle-stimulating hormone (natural-log transformed), and inhibin B (untransformed) were measured in serum. Diminished ovarian reserve was examined dichotomously and defined as an Anti-Müllerian hormone level below 0.7 ng/mL.

Results: The analysis included 703 participants with C-reactive protein measured. In an adjusted linear regression model, a 20% increase in C-reactive protein was associated with a 0.57 pg/mL decrease in inhibin B (95% CI: -0.84 to -0.29 pg/mL) and a 0.535% decrease in follicle-stimulating hormone (95% CI: -1.01 to -0.06). Although there was not a significant relationship between Anti-Müllerian hormone and C-reactive protein, a 20% increase in C-reactive protein was associated with a 0.87% increase in Anti-Müllerian hormone (95% CI: -0.27 to 2.01). C-reactive protein was not associated with the odds of diminished ovarian reserve in an adjusted logistic regression model (OR: 0.97, 95% CI: 0.77-1.20).

Conclusions: Inflammation, as measured by C-reactive protein, is associated with early follicular phase follicle-stimulating hormone and inhibin B, although this is not true of AMH. Inflammation may exert an effect on ovarian function.