Coital Frequency and the Probability of Pregnancy in Couples Trying to Conceive Their First Child: A Prospective Cohort Study in Japan.

Background: Low fertility persists but remains unexplained in Japan. We examined whether the probability of pregnancy was influenced by coital frequency, age, reproductive age (assessed by antimüllerian hormone, AMH), and BMI. Methods: We established a two-year prospective study with a sample of hormonally monitored Japanese women aged 23-34 years wanting to conceive their first child. For a maximum of 24 weeks participants recorded menstrual bleeding, sexual intercourse, ovulation, and pregnancy. Additional information on pregnancy and infertility treatment was collected one and two years after intake. Results: The natural conception rate and coital frequency were both low in this sample. Among 80 participants, 44% (35) naturally conceived in 24 weeks. After two years, 74% (59) of women had delivered or were currently pregnant, 50% (40) due to natural and 24% (19) due to assisted conception, and 5% (4) were lost to follow-up. By two years, 56% (45) of women had sought fertility treatment. In 18% (58/319) of the observed ovarian cycles across 24 weeks there was no intercourse in a fertile period. Higher coital frequency at intake was associated with increased probability of conception by 24 weeks of follow-up (OR 1.23, 95%CI 1.02, 1.47). Chronological age, reproductive age, and BMI were not associated with the probability of pregnancy at 24 weeks. Conclusions: Our results suggest that first, natural conception rates could potentially increase with more frequent and well timed intercourse, and second that further work is needed to understand why even in a motivated sample of women monitoring their fertile periods, both the conception and coitus rates were low.

Sexual Dysfunction and Satisfaction in Japanese Couples During Pregnancy and Postpartum.

INTRODUCTION: Sexual function and frequency can change between couples during pregnancy and postpartum, with a decline in sexual function in women. AIM: To investigate sexual function in couples during pregnancy and postpartum. METHODS: This questionnaire-based cross-sectional descriptive study solicited data from 551 couples, 127 (23%) of whom responded: 15 during the first trimester; 26 during the second trimester; and 21, 22, 21, and 22 at 1, 3, 6, and 12 months postpartum, respectively. The Female Sexual Function Index (FSFI) and International Index for Erectile Function (IIEF) questionnaires were used for female and male participants, respectively, and included questions about delivery, breastfeeding, partner's contribution to housework, and desire to have more children for women, and about aspects of their partner's pregnancy and postpartum life for men. Data about maternal/paternal age, parity, body mass index, and mode of delivery were also collected. MAIN OUTCOME MEASURE: FSFI and IIEF total and subcategory scores with attributable factors. RESULTS: The total and subcategory scores related to female and male sexual functions were lowest at 1 and 3 months postpartum, with 79 women reporting female sexual dysfunction (score <26.55). The FSFI subcategory scores (except desire and satisfaction) differed between 1 and 12 months postpartum. The IIEF scores showed no significant differences. The total mean IIEF scores were 17.9 ± 9.6 and 54.9 ± 12.0 in men with and without erectile dysfunction (ED), respectively. The FSFI scores were 8.6 ± 7.2 and 18.2 ± 8.6 in women whose partner had and did not have ED, respectively. No significant differences (P = .76) were observed between the male satisfaction subcategories. CONCLUSION: Sexual function decreased around the time of delivery for men and women, but did not correlate with the sexual satisfaction of men. Type of delivery, breastfeeding, intimacy, and partner's contribution to housework did not affect sexual dysfunction. Saotome TT, Yonezawa K, Suganuma N. Sexual dysfunction and satisfaction in Japanese couples during pregnancy and postpartum. Sex Med 2018;6:348-355.