Effect of age-difference between heterosexual partners on risk of cervical cancer and human papillomavirus infection

Gravidity modifies the associations of age and spousal age difference with couple's fecundability: a large cohort study from China

STUDY QUESTION

Do couple's age ranges for optimal fecundability, and the associations with fecundability of couple's age combinations and age differences differ with gravidity?

SUMMARY ANSWER

The couple's age range of optimal fecundability and age combinations differed with gravidity, and gravidity might modify the associations of age and spousal age difference with couple's fecundability.

WHAT IS KNOWN ALREADY

Age is one of the strongest determinants of fecundability, but the existing studies have certain limitations in study population, couple's extreme age combinations and age differences, and have not explored whether the association between age and fecundability differs with gravidity.

STUDY DESIGN, SIZE, DURATION

Retrospective cohort study. 5 407 499 general reproductive-aged couples (not diagnosed with infertility) participated in the National Free Pre-conception Check-up Projects during 2015-2017. They were followed up for pregnancy outcomes through telephone interviews every 3 months until they became pregnant or were followed up for 1 year.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The main outcome was time to pregnancy, and the fecundability odds ratios and 95% CIs were estimated using the Cox models for discrete survival time. The associations of age and spousal age difference with fecundability were evaluated by restricted cubic splines.

MAIN RESULTS AND THE ROLE OF CHANCE

In this large cohort of general reproductive-aged population, the age of optimal fecundability of multigravida couples was older than that of nulligravida couples, but their subsequent fecundability declined more sharply with age. The decline in female fecundability was more pronounced with age, with fecundability dropping by ∼30% in both nulligravida and multigravida couples whose female partners aged ≥35 years. In the nulligravida group, the fecundability of couples who were both ≤24 years with the same age was the highest, which decreased steadily with the increase of spousal age difference, and younger male partners did not seem to contribute to improving couple's fecundability. In the multigravida group, couples with female partners aged 25-34 years and a spousal age difference of -5 to 5 years showed higher fecundability, and the effect of spousal age difference on couple's fecundability became suddenly apparent when female partners aged around 40 years. Young male partners were unable to change the decisive effect of female partner's age over 40 years on couple's reduced fecundability, regardless of gravidity.

LIMITATIONS, REASONS FOR CAUTION

Lacking the time for couples to attempt pregnancy before enrollment, and some couples might suspend pregnancy plans during follow-up because of certain emergencies, which would misestimate the fecundability. Due to the lack of information on sperm quality and sexual frequency of couples, we could not adjust for these factors. Moreover, due to population characteristics, the extrapolation of our results required caution.

WIDER IMPLICATIONS OF THE FINDINGS

The couple's age range of optimal fecundability, age combinations, and spousal age difference on fecundability varied with gravidity. Female age-related decline in fecundability was more dominant in couple's fecundability. Targeted fertility guidance should be provided to couples with different age combinations and gravidities.

STUDY FUNDING/COMPETING INTEREST(S)

This research received funding from the Project of National Research Institute for Family Planning (Grant No. 2018NRIFPJ03), the National Key Research and Development Program of China (Grant No. 2016YFC1000307), and the National Human Genetic Resources Sharing Service Platform (Grant No. 2005DKA21300), People's Republic of China. The funders had no role in study design, analysis, decision to publish, or preparation of the manuscript. The authors report no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Religious Affiliation, Daily Spirituals, and Private Religious Factors Promote Marital Commitment Among Married Couples: Does Religiosity Help People Amid the COVID-19 Crisis?

Religious studies are a vital branch of social science that seeks to explain the beliefs of human society and deals with the practices and beliefs of individuals. This distinctive study focuses on such influential aspects of a healthy life, which could play a vital role in the marital quality and matrimonial commitment of individuals. The study principally focused on inspecting the role of religiosity in healthy marital commitment among individuals. It is a distinctive and central value in regulating a healthy social life. This research designed a conceptual model for assessing marital commitment, and the study model comprised two primary variables. The study received datasets through a survey questionnaire based on participants from five private and public sectors. The research study conducted an empirical analysis to test the proposed conceptual framework. The findings exhibited that the value of the R 2 model was 0.484, meaning the level of religiosity had a substantial impression on healthy and lasting marital commitment. According to the final outline of the model factors associated with building religious support factors (β = 0.491), the marital commitment had a better and healthier impact. The goodness-of-fit of the measurement of the conceptual model showed a value of 0.51, which indicated that the theoretical model had sufficient consistency and rationality, and accurately fitted the data. Such an advanced statistical model is missing from the previous literature. The study results provide helpful insight to elucidate the social dynamics of marital commitment. The findings designate that religious practices strengthen and promote nuptial commitment. The study is novel in the context of religiosity impact on martial commitment with a cultural background of Pakistan. The generalizability of the study does not apply to the entire population or other regions. Future studies can investigate other religious variables to explore further research findings. The findings are helpful for decision-makers and policymakers to concentrate on marital issues and challenges confronted by couples worldwide.

Timing, number, and type of sexual partners associated with risk of oropharyngeal cancer

BACKGROUND

Case-control studies from the early 2000s demonstrated that human papillomavirus-related oropharyngeal cancer (HPV-OPC) is a distinct entity associated with number of oral sex partners. Using contemporary data, we investigated novel risk factors (sexual debut behaviors, exposure intensity, and relationship dynamics) and serological markers on odds of HPV-OPC.

METHODS

HPV-OPC patients and frequency-matched controls were enrolled in a multicenter study from 2013 to 2018. Participants completed a behavioral survey. Characteristics were compared using a chi-square test for categorical variables and a t test for continuous variables. Adjusted odds ratios (aOR) were calculated using logistic regression.

RESULTS

A total of 163 HPV-OPC patients and 345 controls were included. Lifetime number of oral sex partners was associated with significantly increased odds of HPV-OPC (>10 partners: odds ratio [OR], 4.3 [95% CI, 2.8-6.7]). After adjustment for number of oral sex partners and smoking, younger age at first oral sex (<18 vs >20 years: aOR, 1.8 [95% CI, 1.1-3.2]) and oral sex intensity (>5 sex-years: aOR, 2.8 [95% CI, 1.1-7.5]) remained associated with significantly increased odds of HPV-OPC. Type of sexual partner such as older partners when a case was younger (OR, 1.7 [95% CI, 1.1-2.6]) or having a partner who had extramarital sex (OR, 1.6 [95% CI, 1.1-2.4]) was associated with HPV-OPC. Seropositivity for antibodies to HPV16 E6 (OR, 286 [95% CI, 122-670]) and any HPV16 E protein (E1, E2, E6, E7; OR, 163 [95% CI, 70-378]) was associated with increased odds of HPV-OPC.

CONCLUSION

Number of oral sex partners remains a strong risk factor for HPV-OPC; however, timing and intensity of oral sex are novel independent risk factors. These behaviors suggest additional nuances of how and why some individuals develop HPV-OPC.

Impacts of human papillomavirus vaccination for different populations: A modeling study

International variations in the prevalence of HPV infection derive from differences in sexual behaviors, which are also a key factor of the basic reproductive number (R0 ) of HPV infection in different populations. R0 affects the strength of herd protection and hence the impact of a vaccination program. Similar vaccination programs may therefore generate different levels of impact depending upon the population's pre-vaccination HPV prevalence. We used IARC's transmission model to estimate (i) the overall effectiveness of vaccination versus no vaccination in women aged 15-34 years measured as percent prevalence reduction (%PR) of HPV16 and (ii) the corresponding herd protection in populations with gender-equal or traditional sexual behavior and with different levels of sexual activity, corresponding to pre-vaccination HPV16 prevalence from 1 to 8% as observed worldwide. Between populations with different levels of gender-equal sexual activity, the highest difference in %PR under girls-only vaccination is observed at 40% coverage (91%PR vs. 48%PR for 1% and 8% pre-vaccination prevalence, respectively). HPV16 elimination is obtained with 55 and 97% coverage, respectively. To achieve desirable levels of HPV16 prevalence after vaccination, different levels of coverage are required in populations with different levels of pre-vaccination HPV16 prevalence, for example, in populations with gender-equal sexual behavior a decrease to 1/1000 HPV16 from pre-vaccination prevalence of 1 and 8% would require coverages of 37 and 96%, respectively. In traditional populations, corresponding coverages would need to be 28 and 93%, respectively. In conclusion, pre-vaccination HPV prevalence strongly influences herd immunity and helps predict the overall effectiveness of HPV vaccination.