How accurate is male recall of reproductive information?

Is the mortality-fertility nexus gendered? A research note on sex differences in the impact of sibling mortality on fertility preferences

Research guided by demographic transition theory has shown that exposure to mortality influences women's fertility preferences and behaviours. Despite the myriad contexts, methodological approaches, and linkages featured in past studies, they have shared a focus on women, leaving questions on the gendered salience of mortality exposures for adults' fertility-related outcomes unanswered. In this research note, we analyse data from three African countries with distinct fertility profiles (Nigeria, Zambia, and Zimbabwe) to examine associations between sibling mortality exposure and ideal family size among women, men, and couples. We also investigate the stability of these associations over time. The associations between adults' sibling mortality exposure and their own and their spouses' ideal family sizes vary across countries. However, the gendered nature of the results in every country and evidence of cross-spousal effects uniformly demonstrate the need to incorporate sex differences into the study of the mortality-fertility link.

The prevalence of couple infertility in the United States from a male perspective: evidence from a nationally representative sample

Infertility is a couple-based fecundity impairment, although population level research is largely based upon information reported by female partners. Of the few studies focusing on male partners, most focus on the utilization of infertility services rather than efforts to estimate the prevalence and determinants of infertility as reported by male partners. Data from a nationally representative sample of men aged 15-44 years who participated in the 2002 National Survey of Family Growth (NSFG) were used to estimate the prevalence of infertility and determinants of longer time-to-pregnancy (TTP) using the novel current duration (CD) approach. Using backward recurrence time parametric survival methods, we estimated infertility prevalence (TTP > 12 months) and time ratios (TR) associated with TTP as derived from males' reported CD of their pregnancy attempt. The estimated prevalence of infertility was 12.0% (95% CI: 7.0, 23.2). Longer TTP was associated with older male age (35-45 vs. 17-24 years) (TR: 2.49; 95% CI: 1.03, 6.03), biological childlessness (TR: 1.53; 95% CI: 1.07, 2.19) and lack of health insurance (TR: 1.73; 95% CI: 1.02, 2.94) after controlling for the differences in couples' age and other socioeconomic factors. The prevalence of infertility based on male reporting is consistent with estimates of infertility in the US found in prospective cohort studies and CD studies based on female reporting. Our findings suggest that male partners can reliably inform about couple infertility. Interventions and services aimed at reducing couple infertility should include attention to male factors associated with longer TTP identified in this study.

Reproductive outcomes in men with prenatal exposure to diethylstilbestrol

OBJECTIVE

To examine prenatal diethylstilbestrol (DES) exposure in relation to male reproductive outcomes.

DESIGN

Prospective observational study.

SETTING

Participants were identified through record review, clinical trial participation, or an obstetrics clinic.

PATIENT(S)

A total of 1,085 DES-exposed and 1,047 unexposed men.

INTERVENTION(S)

Participants were exposed prenatally to DES through the mother's obstetrics care or clinical trial participation.

MAIN OUTCOME MEASURE(S)

Infertility; never fathering a pregnancy or live birth; number of pregnancies or live births fathered.

RESULT(S)

We found little evidence that prenatal DES exposure affects the likelihood of never fathering a pregnancy or live birth, or influences the mean number of fathered pregnancies or live births. Our data suggest that DES-exposed men are slightly more likely to experience infertility (relative risk [RR] = 1.3, 95% confidence interval [CI] = 1.0-1.6). The DES dose and gestational timing did not influence infertility or the number of pregnancies or live births fathered, but results were inconsistent for dose effects on the likelihood of never fathering a pregnancy or a live birth.

CONCLUSION(S)

Prenatal DES exposure may be associated with a slightly increased risk of having an infertility experience, but does not increase the likelihood of never fathering a pregnancy or a live birth, or the number of pregnancies or live births fathered.

Accuracy of men's recall of their partner's time to pregnancy

BACKGROUND

Occupational studies of fertility often rely on men's report of time to pregnancy (TTP). We assessed accuracy of men's report of TTP compared with TTP derived from data from their female partners.

METHODS

Men from the Dieckmann diethylstilbestrol cohort were interviewed to assess fertility. Men were asked TTP for their most recent pregnancies. Their female partner was subsequently interviewed separately; TTP derived from her data was used as the gold standard. Our analysis was based on 202 couples.

RESULTS

Men's report was identical to the women's-derived TTP in 32% of couples; 74% differed by no more than 2 cycles. Men tended to underestimate TTP (mean difference = -1.2 cycles). Weighted kappa was 0.5 overall and varied by the man's education, the number of pregnancies he had fathered, his stated confidence in reporting, his exposure to diethylstilbestrol, pregnancy planning, and whether he was still married to the index partner.

CONCLUSIONS

Overall accuracy of men's report of TTP was reasonably good, particularly for men who had fathered only one pregnancy.

Fertility patterns prior to testicular cancer diagnosis

Although prenatal factors are associated with testicular cancer etiology, few studies have examined the reproductive profiles of men prior to diagnosis. This case--control study investigated fertility patterns prior to testicular cancer diagnosis by comparing pregnancies fathered by 201 men with testicular cancer and those fathered by 204 age- and neighborhood-matched controls. Regardless of histology, men with testicular cancer were less likely to have ever fathered a live-born infant (OR 0.67, 95% CI 0.42--1.06) and had fewer offspring than control men (means 1.8 and 2.1, respectively). Cases were more likely than controls to report having an infertility diagnosis (OR 9.47, 95% CI 1.19--75.2) or a low sperm count (OR 5.85, 95% CI 1.28--26.7) prior to cancer diagnosis. No differences were observed for pregnancy loss. These results indicate that men with testicular cancer may have impaired fecundity and fertility as evidenced by an infertility diagnosis or low sperm count and fewer live births. Further research is needed to determine the extent to which reproductive factors are involved in the etiology of testicular cancer.

Reporting of fertility events by men and women in rural Gambia

We conducted a survey of male and female fertility in rural villages in The Gambia and compared men and women's reports of recent pregnancy events in the aggregate and of children ever born for matched couples. Despite widespread polygyny and sex differences in fertility, men's and women's reports were similar. Small sex differences in reports of recent stillbirths and neonatal deaths were found. For matched couples, husbands reported 0.23 more children ever born than their wives on average, but discordant reporting had little effect on recent marital fertility rates. Modeling of discordant reports indicates that fertility reports are more likely to be underestimated by both men and women for their earliest marriages. Reliable fertility data can be collected from men in this population.

Male infertility risk factors in a French military population

We investigated infertility risk factors by conducting a population-based case-control study in the military population of the French town of Brest. Sixty couples who had sought medical advice for infertility of more than 12 months duration (cases) were compared with 165 couples who had had a child (controls). All the men in these couples had been employed by the military. The infertility risk factors studied were male and female medical factors, occupational and environmental exposures. We obtained age-adjusted odds ratios of 7.4 [95% confidence interval (CI): 1.4--39.5] for testis surgery, and 13.0 for varicocele (95% CI: 1.4--120.3) in men. In logistic regression, the age-adjusted odds ratio for men who had worked in a nuclear submarine was found to be 2.0 (95% CI: 1.0--3.7), and that for heat exposure was 4.5 (95% CI: 1.9--10.6). One limitation of this study is the lack of exposure measurements, especially for potential exposure to nuclear radiation (type of reactor used in nuclear-powered submarines, inability to obtain personal dosimeters worn by military personnel working in nuclear submarines). In conclusion, this study suggests that in this military population, having worked as a submariner in a nuclear-powered submarine, and having worked in very hot conditions, should be considered as risk factors for infertility.

Temporal trends in spontaneous abortion associated with Type 1 diabetes

The objective of this study was to investigate temporal changes in the reported rates of spontaneous abortion associated with Type 1 diabetes. Individuals from the Children's Hospital of Pittsburgh Type 1 Diabetes Registry for 1950-1964 (n=495) completed a self-report reproductive history questionnaire in 1981 that was updated in 1990. Data from both surveys, which proved to be valid and reliable, were utilized for this report. More spontaneous abortions (26.8 vs. 7.7%, P<0.001), stillbirths (4.7 vs. 1.2%, P<0.001) and induced abortions (7.0 vs. 0.9%, P<0.001) were reported for Type 1 diabetic women than for the non-diabetic partners of Type 1 diabetic men. A significant temporal decline in the rates of spontaneous abortion for Type 1 diabetic women was observed (< or = 1969: 26.4%; 1970-1979: 31.0%; 1980-1989: 15.7%; P<0.05). No differences were apparent for the non-diabetic partners of Type 1 diabetic men (< or = 1969: 4.2%; 1970-1979: 9.5%; 1980-1989: 5.7%; P>0.05). Temporal changes in medical care for women with diabetes (i.e. self-monitoring of glycemic control) may have contributed to a recent reduction in spontaneous abortions associated with maternal Type 1 diabetes.