Impact of the menstrual cycle and ethinyl estradiol/etonogestrel contraceptive vaginal ring on granulysin and other mucosal immune mediators

We conducted a prospective, open-label study to determine the effect of the NuvaRing on gene expression in the endocervix and immune-related protein expression in cervicovaginal secretions. Women provided endocervical cytobrush samples during the luteal and follicular phases of the menstrual cycle (as determined by progesterone levels) as well as during NuvaRing use. Gene expression was measured using Illumina Human HT12 v4 BeadChip microarrays. We compared the NuvaRing visit to each phase of the menstrual cycle separately, as well as follicular and luteal phase samples to each other, adjusting for technical batch, presence of blood in vaginal discharge, and BV status by Nugent score, and blocking on participant. We found that gene expression in the endocervical canal changed across the menstrual cycle and in response to NuvaRing use. In particular, we observed a continuum of expression of immune-related genes and gene sets in the endocervical canal: highest during NuvaRing use, intermediate in the follicular phase, and lowest in the luteal phase. We compared endocervical gene expression at three time points: the follicular phase, the luteal phase, and during use of the ethinyl estradiol and etonogestrel contraceptive vaginal ring (NuvaRing, Merck). Repeated samples were obtained from most participants. Menstrual cycle phase was determined based on serum progesterone levels. In a few cases, samples that were expected to follicular or luteal based on the date of the participant’s last menstrual period had discordant progesterone levels. In those cases, menstrual phase was switched and assigned based on progesterone level. Samples were run in two batches. Women were also tested for HSV-2-seropositivity and bacterial vaginosis by Nugent score.