Effects of Multiple Sexual Partners on Health Outcomes

Multiple sexual partners (MSPs) are common in sub-Saharan Africa, especially among young adults.

Forty-eight systematic peer-reviewed studies (2010–2024) reported that MSPs increase the odds of bacterial STIs (OR 1.8–3.5) and viral STIs (OR 1.9–2.5), raise depressive and anxiety symptom prevalence (PR 1.4–2.1), and are linked to higher risks of unintended pregnancy, infertility and adverse birth outcomes (RR 1.3–2.8).

A mixed-methods study in Accra and Kumasi, Ghana, involving 1,200 adults aged 16–55, found that 28 per cent reported two or more partners in the past year (34 per cent of men, 22 per cent of women).

Adjusted logistic regression linked MSPs to a 2.1-fold rise in chlamydia infection, a 1.8-fold rise in depressive symptoms and a 2.4-fold rise in unintended pregnancy. Qualitative data identified stigma and limited youth-friendly services as barriers to testing and care.

The evidence calls for integrated sexual-health programmes and further longitudinal research.

MSPs are a normal part of sexual exploration, but data from sub-Saharan Africa show they markedly increase the burden of STIs, mental health disorders and reproductive complications.

Cultural norms, urban migration and digital dating platforms drive high MSP rates, yet few syntheses have examined the three health domains together.

This article reviews how MSPs affect STI acquisition, mental health status and reproductive outcomes, and outlines policy and research implications.

Methodology
A systematic search was performed in PubMed, Embase and Web of Science using MeSH and free-text terms for “multiple sexual partners,” “sexually transmitted infections,” “mental health,” “reproductive health” and “sub-Saharan Africa.”

Studies published from January 2010 to December 2024 were included if they reported original data on MSPs and at least one of the following: laboratory-confirmed STIs, validated mental health assessments (PHQ-9, GSS-10) or reproductive health indicators (unintended pregnancy, infertility).

Quality was assessed with the Newcastle-Ottawa Scale (scores ≥ 7 considered high) and the Cochrane Risk of Bias tool. Synthesis was primarily narrative, with meta-analysis of homogeneous effect measures (pooled odds ratios for STI outcomes) [Mabiala et al., 2023; Garnett & Anderson, 2020].

A complementary mixed-methods investigation was carried out in Accra and Kumasi, Ghana. Multistage cluster sampling yielded 1,200 adults aged 16–55 (600 per city, balanced by gender and age).

Participants completed a translated questionnaire covering sociodemographics, sexual behaviour, STI testing, mental health screening and reproductive outcomes. Eight focus-group discussions explored cultural norms and barriers to care.

Quantitative data were analysed with Stata 17 using multivariable logistic regression adjusted for age, education and wealth [Appiah et al., 2022]. Qualitative data were examined thematically [Miller & Patel, 2021].

The systematic review of 48 studies consistently showed that MSPs are associated with higher odds of bacterial STIs (OR 1.8–3.5) [Mabiala et al., 2023] and viral STIs (OR 1.9–2.5) [Garnett & Anderson, 2020].

Pooled odds for chlamydia were 2.3 (95 % CI 1.9–2.8) [Mabiala et al., 2023]. Meta-analyses also indicated increased prevalence ratios for depressive and anxiety symptoms (1.4–2.1) [Belay et al., 2023] and higher risk ratios for unintended pregnancy, infertility and adverse birth outcomes (1.3–2.8) [Adeyemi et al., 2021].

In the Ghanaian study, 28  per cent of participants reported two or more sexual partners in the past year, with higher rates among men (34 %) than women (22 %) [Appiah et al., 2022].

After adjusting for sociodemographic factors, MSPs were linked to a 2.1-fold increase in laboratory-confirmed chlamydia infection (OR = 2.1, 95 % CI 1.6–2.7) [Appiah et al., 2022], a 1.8-fold increase in depressive symptoms (OR = 1.8, 95 % CI 1.4–2.3) [Appiah et al., 2022] and a 2.4-fold increase in unintended pregnancy (OR = 2.4, 95 % CI 1.9–3.0) [Appiah et al., 2022].

Focus-group participants highlighted stigma and limited youth-friendly services as major barriers to STI testing and mental health care [Miller & Patel, 2021].

Discussion
The combined evidence confirms that MSPs are a robust risk factor for bacterial and viral STIs [Mabiala et al., 2023; Garnett & Anderson, 2020], depressive and anxiety symptoms [Belay et al., 2023], and adverse reproductive outcomes, particularly unintended pregnancy among women [Adeyemi et al., 2021].

Gender disparity in MSP prevalence mirrors broader sub-Saharan patterns [UNAIDS, 2023] and underscores the need for targeted interventions for men.

Qualitative insights suggest that stigma and inadequate youth-friendly services impede care seeking, indicating that biomedical solutions alone are insufficient [Miller & Patel, 2021].

Integrated programmes that combine behavioural counselling, pre-exposure prophylaxis, HPV vaccination, and structural interventions such as comprehensive sex education and stigma reduction are warranted [Belay et al., 2023; Owusu et al., 2021]. Limitations include the cross-sectional nature of the primary study, reliance on self-reported behaviours, and the exclusion of male reproductive health outcomes [Huang et al., 2020].

Future research should employ longitudinal designs, standardised biological testing and implementation-science methods to address causality and scalability [Michele et al., 2022].

Conclusion
The systematic review and Ghanaian primary study demonstrate that having multiple sexual partners significantly increases the risk of STIs, mental health disorders and adverse reproductive outcomes.

Integrated, multilayered interventions are essential to reduce this public-health burden, especially in high-prevalence settings like Ghana.

Further longitudinal and implementation research is needed to translate these findings into effective, scalable programmes and achieve sexual-health equity across sub-Saharan Africa.

By Dr (ND) Francis Appiah
The writer is a naturopathic doctor