Pregnancy scares and change in contraceptive use

Menstrual Cycle Length Changes Following Vaccination Against Influenza Alone or With COVID-19

Importance

Multiple studies have identified an association between COVID-19 vaccination and menstrual disturbances. Data on whether menstrual health is impacted by other vaccines are needed to counsel individuals about what to expect and to address vaccine hesitancy.

Objective

To assess the association of changes in length of the menstrual cycle with influenza vaccination, with or without concurrent receipt of a COVID-19 vaccine.

Design, Setting, and Participants

This global retrospective cohort study prospectively collected menstrual cycle data from April 25, 2023, to February 27, 2024 (4-5 cycles per individual), among international English-speaking users of a digital birth control application. Participants included individuals aged 18 to 45 years, not using hormonal contraception, and with average cycle lengths of 24 to 38 days in 3 consecutive cycles before receipt of vaccines.

Exposure

Seasonal influenza vaccination with or without concurrent receipt of COVID-19 vaccine.

Main Outcome and Measure

The primary outcome consisted of adjusted mean within-individual changes of menstrual cycle length assessed by vaccination group. Secondary analysis evaluated the phase of menstrual cycle at time of vaccination.

Results

A total of 1501 individuals met the inclusion criteria, of whom 791 were vaccinated for influenza only and 710 were concurrently vaccinated for influenza and COVID-19. By race and ethnicity, 1 participant (0.1%) was American Indian or Alaska Native; 10 (0.7%), Asian; 3 (0.2%), Black; 15 (1.0%), Hispanic or Latina; 1 (0.1%), Middle Eastern or North African; 368 (24.5%), White; and 19 (1.3%), other; and 1084 (72.2%), missing. Most of the cohort was younger than 35 years (1230 [82.0%]), had at least a college degree (1122 [74.8%]), and was located in the US or Canada (938 [62.5%]). Individuals vaccinated for influenza alone experienced an adjusted mean increase of 0.40 (95% CI, 0.08-0.72) days, while those vaccinated concurrently for influenza and COVID-19 experienced a mean increase of 0.49 (95% CI, 0.16-0.83) days (P = .69 for difference between vaccine groups). A total of 37 individuals (4.7%) experienced a change in cycle length of at least 8 days with influenza vaccine only and 42 (5.9%) with concurrent receipt of both vaccines (P = .28). In the postvaccination cycle, both vaccination groups returned to their prevaccination cycle lengths. Menstrual cycle changes occurred with vaccination in the follicular phase but not the luteal phase.

Conclusions and Relevance

In this cohort study of individuals with regular menstrual cycles, influenza vaccine given alone or in combination with a COVID-19 vaccine was associated with a small but temporary change in menstrual cycle length. These findings may help clinicians confirm the utility of vaccination for patients with concerns about menstrual adverse effects of vaccination.

Drivers of contraceptive non-use among women and men who are not trying to get pregnant

This study examines an inconsistency between an attitude and a behaviour: non-use of contraception among people who are not trying to get pregnant. More than one in four people in that situation report not using contraception 'sometimes' or 'always' and consequently face the risk of pregnancy. We test three potential explanations: acceptability of having (further) children; perceived low pregnancy risk; and perceived social pressure. Using 10 waves of the German pairfam panel, we estimate sex-specific between-within models, where each explanation is tested by several indicators. We find evidence for the explanation of a(nother) child being considered acceptable: a positive fertility desire increases contraceptive non-use among women and men, and relationship duration increases it among women. Supporting the explanation of low perceived pregnancy risk, analyses show that perceived infertility, breastfeeding, and age increase the probability of non-use of contraception for women and men. However, there is no strong evidence for perceived social pressure affecting contraceptive non-use.

Make It or Break It? Pregnancy Scares and Romantic Relationship Dissolution

Young adult romantic relationships have undergone significant changes in recent decades, resulting in such distinct demographic trends as rising rates of relationship dissolution. Union dissolution during young adulthood can influence future relationship stability, financial well-being, and health. Reproductive experiences are an important factor that can shape relationship stability. Much of past research, however, has focused on the impact of childbearing on relationship stability while less attention has been paid to other reproductive experiences that could also shape relationship stability, such as pregnancy scares. A pregnancy scare is when a woman suspects she has an undesired pregnancy but later discovers she is not pregnant. This experience might increase or decrease relationship stability. Drawing on data collected from young women in the Relationship Dynamics and Social Life study, this analysis examines the association between pregnancy scares and union dissolution. Results suggest that pregnancy scares are negatively associated with union dissolution, and this relationship persists over time; however, this association varies by relationship type, with serious dating relationships experiencing the most protective benefits.

DYnamics of Contraception in Eswatini (DYCE): protocol for a high-frequency, longitudinal cell phone survey

INTRODUCTION

By 2030, an estimated 42% of the world's adolescent girls and young women (AGYW) will live in sub-Saharan Africa (SSA), where a quarter of AGYW pregnancies are undesired and AGYW represent 75% of new HIV infections. Most AGYW in SSA use short-acting contraceptive methods, including many who rely solely on condoms, which results in variable patterns of protection against undesired pregnancies and HIV. Dynamics of contraceptive use and HIV prevention efforts are poorly understood but the DYnamics of Contraception in Eswatini study will contribute to the understanding of the complex relationship between sexual behaviours, risk perception and HIV and pregnancy prevention.

METHODS AND ANALYSIS

All AGYW 18-24 years who participated in a 2021 nationally representative, population-based (face-to-face) HIV survey, consented to future research and provided a mobile phone number will be contacted for enrolment. Consenting AGYW will complete a baseline questionnaire and be surveyed biweekly for 2 years. The three objectives of the study are to (1) investigate how changing individual context (schooling, income, residential mobility) impact contraceptive use; (2) examine the relationship between pregnancy desires and contraceptive use and (3) test whether changes in a woman's perception of her HIV risk changes her probability of contraceptive use and HIV protective behaviours. Data collection will take place from March 2024 to March 2026 via computer-assisted telephone interviews. During recruitment (March-April 2024), two interviewers called 794 AGYW, of whom 326 completed the baseline questionnaire (41%) and 321 consented to biweekly follow-up (40% American Association for Public Opinion Research response rate #1). Analyses will mainly use hybrid within-between logistic regression models.

ETHICS AND DISSEMINATION

This protocol was reviewed and approved by the Eswatini National Health Research Review Board in 2024 and Columbia University Medical Center Institutional Review Board in 2023. Findings from the study will inform the Eswatini Ministry of Health approaches to mitigating undesired pregnancies and HIV among AGYW. Second, few examples exist of high-frequency longitudinal data collection in SSA, and this study will contribute to the survey method knowledge. Finally, the rich dataset will available for secondary data analysis.

COVID-19 vaccination and menstrual cycle characteristics: A prospective cohort study

We prospectively examined the association between COVID-19 vaccination and menstrual cycle characteristics in an internet-based prospective cohort study. We included a sample of 1,137 participants who enrolled in Pregnancy Study Online (PRESTO), a preconception cohort study of couples trying to conceive, during January 2021-August 2022. Eligible participants were aged 21-45 years, United States or Canadian residents, and trying to conceive without fertility treatment. At baseline and every 8 weeks for up to 12 months, participants completed questionnaires on which they provided information on COVID-19 vaccination and menstrual cycle characteristics, including cycle regularity, cycle length, bleed length, heaviness of bleed, and menstrual pain. We fit generalized estimating equation (GEE) models with a log link function and Poisson distribution to estimate the adjusted risk ratio (RR) for irregular cycles associated with COVID-19 vaccination. We used linear regression with GEE to estimate adjusted mean differences in menstrual cycle length associated with COVID-19 vaccination. We adjusted for sociodemographic, lifestyle, medical and reproductive factors. Participants had 1.1 day longer menstrual cycles after receiving the first dose of COVID-19 vaccine (95 % CI: 0.4, 1.9) and 1.3 day longer cycles after receiving the second dose (95 % CI: 0.2, 2.5). Associations were attenuated at the second cycle post-vaccination. We did not observe strong associations between COVID-19 vaccination and cycle regularity, bleed length, heaviness of bleed, or menstrual pain. In conclusion, COVID-19 vaccination was associated with a ∼1 day temporary increase in menstrual cycle length, but was not appreciably associated with other menstrual cycle characteristics.

Pregnancy scares, pregnancy uncertainty, and abortion attitude change

Women's attitudes towards abortion are often assessed infrequently in their lives. This measurement may not capture how lifetime events, such as reproductive experiences, potentially influence attitudes towards abortion. Although reproductive attitudes can fluctuate with life's circumstances, there is little research on how abortion attitudes may change when a woman suspects she might be pregnant. Using an intensive longitudinal dataset collected in Michigan, the Relationship Dynamics and Social Life (RDSL) study (2008-2012), we test the relationship between the timing of pregnancy scares and uncertainty and abortion attitudes using hybrid effects models. We find that women become less supportive of abortion while experiencing a pregnancy scare or uncertainty; however, this association exists only during a scare or uncertainty. These findings highlight that abortion attitudes may change when a woman suspects she might be pregnant. However, attitudinal change may not last past this period.

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.

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.

What are We Forgetting? Sexuality, Sex, and Embodiment in Abortion Research

Abortion has been alternately legalized and criminalized, tacitly approved of, and stigmatized, in various settings over time. The contours of its treatment are dependent on social and political contexts, including concern over women's sexuality, but it is not clear that existing conceptual frameworks enable expansive examination of the relationship between abortion and sexuality. We conduct a critical interpretive synthesis review of the literature that jointly engages with sexuality and abortion, focusing on the U.S., to highlight the frameworks that authors use to understand the relationship between the two. We find two conceptual frameworks of abortion and sexuality in operation: one that treats the two as discrete, causal variables that operate at the individual level; and another that focuses on how beliefs about what constitutes (in)appropriate sexuality explain ideological positions on abortion. We identify limitations of both frameworks and propose a new conceptual framework - one that highlights sexual embodiment - to inspire future research in this area and generate opportunities for knowledge extension. Such an approach, we contend, can elucidate broader social forces that shape both abortion and sexuality and bring research on abortion into conversation with recent scholarship on the important role of sexuality in other sexual and reproductive domains.

Changes in pregnancy desire after a pregnancy scare in a random sample of young adult women in a Michigan county

OBJECTIVES

We examined whether and how long young women became more or less likely to desire a pregnancy after experiencing a "pregnancy scare."

STUDY DESIGN

We used data from the Relationship Dynamics and Social Life (RDSL) study, based on a random, population-based sample of 992 young women from a county in Michigan. They were interviewed weekly for 2.5 years. We used fixed-effects logistic regression models to predict pregnancy desire after a pregnancy scare.

RESULTS

Of the 759 sexually experienced women we analyzed, 103 (14%) experienced 128 pregnancy scares. A woman's (adjusted) odds of desiring a pregnancy were 3.70 (95% CI 2.27-6.02) times higher during the week after, 3.04 (95% CI 2.30-4.10) times higher during the month after a pregnancy scare, and 2.31 (95% CI 1.71-3.11) times higher during all weeks after the pregnancy scare, compared to her other weeks during the study period. In a final model directly comparing each period to all weeks before the pregnancy scare, the odds of pregnancy desire were highest (aOR 5.08, 95% CI 3.06-8.42) during the first week, slightly smaller (aOR 3.01, 95% CI 2.11 - 4.30) during the subsequent three weeks, and remained elevated (aOR 1.58, 95% CI 1.19-2.09) throughout the remainder of the study period.

CONCLUSIONS

Our analyses suggest that the experience of a pregnancy "scare" does not scare young women away from wanting pregnancies. On the contrary, the state of possibly being pregnant actually made young women in our study more likely to want to be pregnant, on average.

IMPLICATIONS

Very few young women desire a pregnancy during the transition to adulthood; however, a salient life event like a pregnancy scare can abruptly generate a desire for pregnancy. Our study contributes to efforts to help women implement their pregnancy desires by furthering our understanding of those desires and the contexts in which they are formed.

Pathways to Parenthood in Social and Family Context: Decade in Review, 2020

OBJECTIVE

This article reviews research from the past decade on patterns, trends, and differentials in the pathway to parenthood.

BACKGROUND

Whether, and under what circumstances, people become parents has implications for individual identity, family relationships, the well-being of adults and children, and population growth and age structure. Understanding the factors that influence pathways to parenthood is central to the study of families and can inform policies aimed at changing childbearing behaviors.

METHOD

This review summarizes recent trends in fertility as well as research on the predictors and correlates of childbearing, with a focus on the United States and on research most relevant to family scholars. We document fertility differentials and prevailing explanations for variation across sub-groups and discuss alternative pathways to parenthood, such as adoption. The article suggests avenues for future research, outlines emerging theoretical developments, and concludes with a discussion of fertility policy.

RESULTS

U.S. fertility has declined in recent years; whether fertility rates will increase is unclear. Elements of the broader social context such as the Great Recession and increasing economic inequality have impacted pathways to parenthood, and there is growing divergence in behaviors across social class. Scholars of childbearing have developed theories to better understand how childbearing is shaped by life course processes and social context.

CONCLUSION

Future research on the pathways to parenthood should continue to study group differentials, refine measurement and theories, and better integrate men and couples. Childbearing research is relevant for social policy, but ideological factors impact the application of research to policy.