Timing of Coronavirus Disease 2019 (COVID-19) Vaccination and Effects on Menstrual Cycle Changes.

OBJECTIVE: To assess whether menstrual cycle timing (follicular or luteal phase) of coronavirus disease 2019 (COVID-19) vaccine administration is associated with cycle length changes. METHODS: We used prospectively collected (2021-2022) menstrual cycle tracking data from 19,497 reproductive-aged users of the application "Natural Cycles." We identified whether vaccine was delivered in the follicular or luteal phase and also included an unvaccinated control group. Our primary outcome was the adjusted within-individual change in cycle length (in days) from the average of the three menstrual cycles before the first vaccination cycle (individuals in the unvaccinated control group were assigned a notional vaccine date). We also assessed cycle length changes in the second vaccination cycle and whether a clinically significant change in cycle length (8 days or more) occurred in either cycle. RESULTS: Most individuals were younger than age 35 years (80.1%) and from North America (28.6%), continental Europe (33.5%), or the United Kingdom (31.7%). In the vaccinated group, the majority received an mRNA vaccine (63.8% of the full sample). Individuals vaccinated in the follicular phase experienced an average 1-day longer adjusted cycle length with a first or second dose of COVID-19 vaccine compared with their prevaccination average (first dose: 1.00 day [98.75% CI, 0.88-1.13], second dose: 1.11 days [98.75% CI, 0.93-1.29]); those vaccinated in the luteal phase and those in the unvaccinated control group experienced no change in cycle length (respectively, first dose: -0.09 days [98.75% CI, -0.26 to 0.07], second dose: 0.06 days [98.75% CI, -0.16 to 0.29], unvaccinated notional first dose: 0.08 days [98.75% CI, -0.10 to 0.27], second dose: 0.17 days [98.75% CI, -0.04 to 0.38]). Those vaccinated during the follicular phase were also more likely to experience a clinically significant change in cycle length (8 days or more; first dose: 6.8%) than those vaccinated in the luteal phase or unvaccinated (3.3% and 5.0%, respectively; P <.001). CONCLUSION: COVID-19 vaccine-related cycle length increases are associated with receipt of vaccination in the first half of the menstrual cycle (follicular phase).

Public perceptions of abortion complications.

BACKGROUND: Misinformation contributes to the perception that abortion has substantial health risks, despite the known safety of medication and aspiration abortion. We lack detailed information about which health risks the public believes are most likely. OBJECTIVE: This study aimed to describe public perception of short- and long-term risks of abortion. STUDY DESIGN: We conducted a cross-sectional survey of US residents aged ≥18 years using Amazon Mechanical Turk (MTurk). We collected information regarding participant demographics, reproductive history, political views, and position on abortion restrictions. We provided participants with a list of 9 short-term and 15 long-term possible complications and asked them to indicate whether they occurred never (0%), very rarely (<1%), rarely (1%-5%), occasionally (5%-20%), or frequently (>20%) following abortion. We used descriptive statistics to understand our population demographics and to capture the perceived incidence of all complications. We created a binary indicator of answering all risk estimates incorrectly vs at least 1 estimate correctly, separately for all long-term possible complications, and the 2 short-term risks of infection and bleeding. We determined the proportion of individuals who responded incorrectly to all questions in each category and used multivariable logistic regression to identify factors associated with incorrect perceptions about the risks of abortion. RESULTS: For all listed complications, participant (N=1057) estimates of risk were higher than the known incidence. For both short-term risks of bleeding and infection, over 40% of participants reported that these outcomes occur occasionally or frequently. Similarly, for both long-term risks of depression and anxiety, over 60% of respondents reported that these outcomes occur occasionally or frequently after abortion. Participants reported that possible complications known to not be associated with abortion, including hair loss, future pregnancy complications, breast cancer, and cosmetic disfigurement, occurred at least rarely. Nearly one-quarter of participants responded that death occurs occasionally or frequently (in over 5% of abortions), and 79% of participants responded that breast cancer can result from abortion. One-quarter (24.9%) of participants incorrectly overestimated both short-term outcomes of infection and bleeding, whereas 19.5% answered all long-term complication questions incorrectly, including outcomes that never occur. On multivariable analyses, we identified that the participants most likely to incorrectly identify risks of abortion identified as Asian or Black race/ethnicity, were from rural communities, or believed that abortion should have more legal restrictions. CONCLUSION: The public perceives abortion to be much riskier than it actually is. This information can be used to develop targeted clinical and public health efforts to disseminate the true risks of abortion.

Hormonal regulation of non-cystic fibrosis transmembrane conductance regulator ion channels in the endocervix.

OBJECTIVE: To characterize ion channel expression and localization in the endocervix under different hormonal conditions using a nonhuman primate primary endocervical epithelial cell model. DESIGN: Experimental. SETTING: University-based, translational science laboratory. INTERVENTIONS: We cultured and treated conditionally reprogrammed primary rhesus macaque endocervix cells with estradiol and progesterone and measured gene expression changes for several known ion channel and ion channel regulators of mucus secreting epithelia. Using both rhesus macaque endocervical samples and human samples, we localized channels in the endocervix using immunohistochemistry. MAIN OUTCOME MEASURES: The relative abundance of transcripts was evaluated using real-time polymerase chain reaction. Immunostaining results were evaluated qualitatively. RESULTS: Compared with controls, we found that estradiol increased gene expression for ANO6, NKCC1, CLCA1, and PDE4D. Progesterone down-regulated gene expression for ANO6, SCNN1A, SCNN1B, NKCC1, and PDE4D (P≤.05). Immunohistochemistry confirmed endocervical cell membrane localization of ANO1, ANO6, KCNN4, LRR8CA, and NKCC1. CONCLUSIONS: We found several ion channels and ion channel regulators that are hormonally sensitive in the endocervix. These channels, therefore, may play a role in the cyclic fertility changes in the endocervix and could be further investigated as targets for future fertility and contraceptive studies.

The effect of deliberate non-adherence to a norgestrel progestin-only pill: A randomized, crossover study.

OBJECTIVES: To estimate the effects on cervical mucus, ovarian activity and theoretical contraceptive protection of a 6-hour delay and of missing one norgestrel 0.075 mg progestogen-only pill. STUDY DESIGN: In a prospective, two-site, randomized, crossover study, healthy women aged 18 to 35 with BMI <32.0 kg/m² and regular ovulatory cycles completed a baseline 28-day cycle with correct daily pill use followed by two intervention cycles in which, around mid-cycle, one pill was taken 6 hours late or missed completely. We undertook ovarian ultrasonography, estradiol and progesterone measurement, and cervical mucus assessments every 3 to 4 days (daily around the time of the incorrect use) and based the theoretical contraceptive protection score on ovarian activity status, cervical mucus and their temporal relationship. RESULTS: Of 91 potential participants screened, 52 started the study and 46 provided complete data for each intervention cycle. Fourteen participants (30%) ovulated in each of the two intervention cycles, with four during the delayed pill cycle and two during the missed pill cycle having an abnormal luteal phase. Seven participants in the delayed pill cycle, and six with a missed pill had elevated cervical mucus scores temporally associated with the intervention. However only two women, one in the delayed pill cycle and one in the missed pill cycle, had cervical mucus scores in the range considered favorable for fertility. CONCLUSIONS: Delayed or missed intake of a single norgestrel 0.075 mg progestogen-only pill appears to have little effect on theoretical contraceptive efficacy. IMPLICATIONS: This biomedical study suggests that taking a norgestrel 0.075mg progestogen-only pill 6 hours late or missing one pill have little effect on ovarian activity or cervical mucus and may not jeopardize contraceptive efficacy. Correlation with typical use outcomes is necessary to confirm pregnancy risk with delayed or missed norgestrel intake.

Association between menstrual cycle length and covid-19 vaccination: global, retrospective cohort study of prospectively collected data.

OBJECTIVES: To identify whether covid-19 vaccines are associated with menstrual changes in order to address concerns about menstrual cycle disruptions after covid-19 vaccination. DESIGN: Global, retrospective cohort study of prospectively collected data. SETTING: International users of the menstrual cycle tracking application, Natural Cycles. PARTICIPANTS: 19 622 individuals aged 18-45 years with cycle lengths of 24-38 days and consecutive data for at least three cycles before and one cycle after covid (vaccinated group; n=14 936), and those with at least four consecutive cycles over a similar time period (unvaccinated group; n=4686). MAIN OUTCOME MEASURES: The mean change within individuals was assessed by vaccination group for cycle and menses length (mean of three cycles before vaccination to the cycles after first and second dose of vaccine and the subsequent cycle). Mixed effects models were used to estimate the adjusted difference in change in cycle and menses length between the vaccinated and unvaccinated. RESULTS: Most people (n=15 713; 80.08%) were younger than 35 years, from the UK (n=6222; 31.71%), US and Canada (28.59%), or Europe (33.55%). Two thirds (9929 (66.48%) of 14 936) of the vaccinated cohort received the Pfizer-BioNTech (BNT162b2) covid-19 vaccine, 17.46% (n=2608) received Moderna (mRNA-1273), 9.06% (n=1353) received Oxford-AstraZeneca (ChAdOx1 nCoV-19), and 1.89% (n=283) received Johnson & Johnson (Ad26.COV2.S). Individuals who were vaccinated had a less than one day adjusted increase in the length of their first and second vaccine cycles, compared with individuals who were not vaccinated (0.71 day increase (99.3% confidence interval 0.47 to 0.96) for first dose; 0.56 day increase (0.28 to 0.84) for second dose). The adjusted difference was larger in people who received two doses in a cycle (3.70 days increase (2.98 to 4.42)). One cycle after vaccination, cycle length was similar to before the vaccine in individuals who received one dose per cycle (0.02 day change (99.3% confidence interval -0.10 to 0.14), but not yet for individuals who received two doses per cycle (0.85 day change (99.3% confidence interval 0.24 to 1.46)) compared with unvaccinated individuals. Changes in cycle length did not differ by the vaccine's mechanism of action (mRNA, adenovirus vector, or inactivated virus). Menses length was unaffected by vaccination. CONCLUSIONS: Covid-19 vaccination is associated with a small and likely to be temporary change in menstrual cycle length but no change in menses length.

Functional evaluation of the cystic fibrosis transmembrane conductance regulator in the endocervix†.

The cystic fibrosis transmembrane conductance regulator (CFTR) is an apical membrane chloride/bicarbonate ion channel in epithelial cells. Mutations in CFTR cause cystic fibrosis, a disease characterized by thickened mucus secretions and is associated with subfertility and infertility. CFTR function has been well characterized in vitro and in vivo in airway and other epithelia studies. However, little is known about CFTR function in the cervix in health and its contribution to cyclic regulation of fertility from endocervical mucus changes. Contributing to this research gap is the lack of information on the effect of sex steroid hormones on CFTR expression in cervical epithelial cells across the menstrual cycle. Herein, we demonstrate the hormonal regulation of CFTR expression in endocervical cells both in vitro and in vivo, and that conditionally reprogrammed endocervical epithelial cells can be used to interrogate CFTR ion channel function. CFTR activity was demonstrated in vitro using electrophysiological methods and functionally inhibited by the CFTR-specific inhibitors inh-172 and GlyH-101. We also report that CFTR expression is increased by estradiol in the macaque cervix both in vitro and in vivo in Rhesus macaques treated with artificial menstrual cycles. Estrogen upregulation of CFTR is blocked in vivo by cotreatment with progesterone. Our findings provide the most comprehensive evidence to date that steroid hormones drive changes in CFTR expression. These data are integral to understanding the role of CFTR as a fertility regulator in the endocervix.

Mechanism of action of a 0.075 mg norgestrel progestogen-only pill 2. Effect on cervical mucus and theoretical risk of conception.

OBJECTIVE: To evaluate the cervical mucus effects of a norgestrel 0.075 mg progestin-only contraceptive pill over a 28-day cycle. STUDY DESIGN: We recruited persons ages 18 to 35 with normal cycles at 2 US academic medical centers. Participants took norgestrel 0.075 mg daily for 28 days at the same time (within a 3 hour window) daily, recorded through a text-message based e-diary. We extracted cervical mucus using a standardized aspiration technique on the day of pill initiation and then at least every 3 to 4 days over the cycle. We monitored subjects for follicular activity with transvaginal ultrasound examination and blood sampling for ovarian hormones and gonadotropins at each visit. We assessed cervical mucus scoring using a 4-category/12-point modified Insler scale (score ≥9 [favoring fertility], 5-8 [intermediate], and ≤4 [unfavorable to fertility]). We stratified cervical mucus scores by serum estradiol levels and ovulatory status based on a modified Hoogland score. RESULTS: Excluding enrollment, we collected and evaluated 413 mucus samples from 51 participants. Participants had a median mucus score of 0 (Interquartile Range 0, 2); most had scores ≤4 (samples = 385, 93%) and none had a score ≥9 favoring fertility. Seventeen (33%) participants ovulated, of which 14 (82%) had unfavorable mucus scores (≤4) at the time of ovulation and 3 (18%) had intermediate scores (5-8). CONCLUSIONS: Norgestrel 0.075 mg daily prevents mucus changes that favor fertility, even during ovulatory cycles. IMPLICATIONS: Daily administration of norgestrel 0.075 mg over an initial 28-day cycle did not result in fertile cervical mucus. Although approximately one-third of users ovulated in this first cycle of pill use, contraceptive efficacy may be maintained by mucus effects.

Mechanism of action of norgestrel 0.075 mg a progestogen-only pill. I. Effect on ovarian activity.

OBJECTIVE: To explore the effect on ovarian activity and ovulation of 28 days of correct daily use of a progestogen-only pill containing norgestrel 0.075 mg. STUDY DESIGN: We performed a prospective, randomized, crossover study at 2 US sites, recruiting healthy women of reproductive age to use norgestrel 0.075 mg daily for three 28-day treatment cycles. We monitored ovarian activity every 3 to 4 days with reproductive hormone measurements and ovarian ultrasonography. Participants recorded pill use in daily diaries. An adjudication committee independent of the research sites assessed ovarian activity using a modified Hoogland score combining hormone concentrations and follicle diameter and appearance (quiescence 1-3, ovarian activity without ovulation 4-5, and ovulatory/postovulatory 6-7). RESULTS: We report here the findings of the initial 28-day treatment cycle in which 51 of 52 recruited participants provided data sufficient for analysis. Two thirds of subjects had no evidence of ovulation (34/51, 66.6%); eight of these (15.7%) had quiescent ovaries (follicle <13 mm diameter) and 26 (51%) had follicular development (follicle >13 mm diameter) without ovulation. Seventeen participants ovulated, of whom 12 (23.5%) had a normal, and 5 (9.8%) an abnormal luteal phase. Persistent ovarian follicles were common among women who had ovarian activity without ovulation, 17 of 26 participants (65.4%) had a large follicle which persisted beyond 28 days. CONCLUSION: During 28 days of exposure to a norgestrel 0.075 mg progestogen-only pill, most women had no evidence of ovulation. IMPLICATIONS: Ovulation inhibition and follicle growth disturbance are important in the mechanism of action of a progestogen-only pill containing norgestrel 0.075 mg.

Comparing cervical mucus changes in response to an oral progestin or oestrogen withdrawal in ovarian-suppressed women: a clinical pilot.

Purpose: Prior studies evaluating the effect of administered progestogens on peak cervical mucus have not controlled for the influence of endogenous hormones. To address this, we treated women with a gonadotropin-releasing hormone (GnRH) agonist to suppress the hypothalamus-pituitary-ovarian (HPO) axis and used transdermal oestradiol replacement to stimulate peak cervical mucus and then evaluated the effects of an oral progestin or oestradiol withdrawal. Materials and methods: We used a crossover design to examine cervical mucus changes in women receiving transdermal oestradiol replacement following intramuscular administration of leuprolide acetate. After increasing oestradiol patches to mid-cycle levels, subjects were assigned to either 0.35 mg oral norethindrone with continuation of the patches (NET) or oestradiol withdrawal by patch removal (E2WD). We collected serum and cervical mucus samples at 0, 2, 4, 6, 22 and 24 h following the intervention. Results: We analysed 12 cycles (6 NET, 6 E2WD) from three subjects. Baseline cervical mucus scores were favourable to sperm penetration [NET median 11, interquartile range (9-12), E2WD 13 (12-13)]. Two hours after removal of oestradiol patch or administration of norethindrone, cervical mucus scores declined [NET 8.5 (4-9), E2WD 10.5 (10-12)]. Low cervical mucus scores persisted at 24 h with NET [8.0 (7-8)] but not E2WD [10.5 (8-11)]. Conclusions: We observed a rapid decline in cervical mucus Insler scores following administration of a single dose of oral norethindrone, and scores remained lower and unfavourable through 24 h. Oestradiol withdrawal did not result in similar unfavourable changes.

Appraising cervical mucus: a new approach to evaluating contraceptives.

PURPOSE: Timing of sample collection represents a major source of variability in studies evaluating the effects of administered agents on cervical mucus in naturally-cycling women. We sought to create and validate an artificial model of the cervical mucus cycle using exogenous E2 and P4 replacement in ovarian suppressed women. MATERIALS AND METHODS: We conducted a prospective experiment (clinicaltrials.gov, NCT02969590) examining cervical mucus changes in six women during natural and artificial menstrual cycles [leuprolide acetate, estradiol transdermal patch (0.05-0.3 mg/day) and progesterone 200 mg/day]. We collected serum and mucus samples at each visit corresponding to early, mid and late follicular, ovulation and mid-luteal time points in the natural and artificial cycles. We evaluated mucus according to the modified Insler score described in the WHO laboratory Manual for the Examination and Processing of Human Semen. RESULTS: We enrolled healthy women between 27 and 40 years of age. All of the subjects achieved a mucus score of ≥10 both in the natural cycle and during peak estradiol replacement levels (0.3 mg/day) in the artificial cycle. During the simulated luteal phase, all mucus scores were ≤5 (median 3.5; range 1-5), similar to scores seen in the luteal phase of natural cycles (median 1; range 1-3). CONCLUSIONS: Our artificial cycle model (leuprolide acetate suppression) and dose escalation with estradiol patches produced favourable cervical mucus with mucus scores similar to those in the periovulatory phase of natural menstrual cycles. Additional studies are needed to validate the model for evaluation of mucus effects of contraceptive agents.