Sexual functioning and its determinants in individuals and their partners with unexplained infertility

What is the prevalence of sexual dysfunction, and what are the determinants of sexual (dys)functioning in couples with newly diagnosed unexplained infertility?

At least one in four couples are at risk of sexual dysfunction, and higher age, longer infertility duration, higher sperm quality, and poorer personal and relational well-being were associated with decreased sexual functioning.

Many couples diagnosed with unexplained infertility have the ability to conceive naturally over time, but infertility is linked to reduced sexual functioning, which can hinder conception. Surprisingly, sexual functioning, its risk factors, and partner interdependence are still understudied in unexplained infertility, while knowing the risk factors for reduced sexual functioning would enable fertility specialists to timely diagnose, prevent, or treat sexual dysfunction, and in this way improve natural conception rates.

A cross-sectional survey, which also serves as the baseline assessment of a randomized controlled trial (RCT, 2016-2021). A total of 700 heterosexual couples were addressed.

Dutch heterosexual couples (female age 18-38 years) who were able to have coitus and were recently diagnosed with unexplained infertility in secondary or tertiary clinics were eligible. The main outcome measures were sexual functioning as a continuous variable and female and erectile dysfunction based on cut-off scores of the Female Sexual Function Index and International Index of Erectile Function. Determinants included demographic, lifestyle, and diagnostic factors, as well as personal and relational well-being, which were assessed with the Hospital Anxiety and Depression Scale and the Revised Dyadic Adjustment Scale. Sexual (dys)functioning and determinants were subjected to dyadic analysis followed by linear regression.

A total of 581 (83%) women and 478 (68%) men completed the questionnaires. Complete couple data were available for 451 (68.9%) couples. About 1 in 4 women (24.3%) and 1 in 14 men (7.3%) were at risk for, respectively, female sexual dysfunction and erectile dysfunction after a fertility work-up. Couples had a mean coital frequency of seven times per month (SD: 2.7). Higher female and male sexual desire (β: 0.04, P < 0.01 and β: 0.02, P < 0.02) and satisfaction (β: 0.03, P < 0.01 and β: 0.06, P < 0.01), but not orgasm, were significantly associated with increased coital frequency. Lower female sexual functioning (β) or dysfunction (OR) was associated with own age (β: -0.64, OR: 1.12), anxiety (β: -9.47, OR: 4.22), depression (β: -7.61, OR: 3.23), relationship distress (β: -8.97, OR: 2.04), and total motility sperm count (β: -4.88). Lower male sexual functioning was associated with anxiety (β: -5.03), depression (β: -3.65), relationship distress (β: -5.77), and partner's age (β: -0.46) and couple's duration of infertility (β: -0.24, OR: 1.06).

The study is prone to selection bias given the inclusion of couples seeking medical help and consenting to an RCT. Not all previously identified determinants of sexual functioning were studied due to factors such as missing data, low case numbers, or not being assessed in the Pleasure&Pregnancy (P&P) RCT.

Clinicians advising couples with unexplained infertility to continue natural conception, given their good prognosis, need to be aware that at least one in four couples are at risk for a sexual dysfunction. Clinicians should consider risk factors of reduced sexual functioning, take a sexual anamnesis, and advise face-to-face or digital (e.g. via website or app) sex counselling and treatment, if indicated.

This work was supported by the Netherlands Organization for Health Research and Development (ZonMW reference: 843001605), University of Amsterdam and Flanders Research Foundation. The funders have no role in considering the design of the study, or collection, analysis, and interpretation of the data, or writing of the report. C.B.L. was the Editor-in-Chief of Human Reproduction until 1 January and has received speakers honorarium and travel support from Merck and Organon.

Baseline assessment of the P&P RCT with trial registration number NTR5709.