Unwanted side-effects are the leading cause of dissatisfaction and discontinuation of hormonal contraceptives worldwide. Yet contraceptive side-effects are commonly dismissed as minor and/or misconceptions within global health, in part due to the paucity of quantitative data on side-effects symptoms. This research aimed to (1) compare changes in symptom number and severity among hormonal contraceptive users and a control group over a 3-months period, (2) identify risk factors for such changes, and (3) evaluate their impact on women’s daily lives. We conducted an observational baseline-controlled prospective cohort study among injectable and implant users and a control group of non-users in Central Oromia, Ethiopia. Sociodemographic, diet, activity data and monthly side-effect symptoms were collected from pre-initiation to three months. Multilevel models adjusted for temporal autocorrelation were used to evaluate change in the number and severity of symptoms. Minimally adjusted models were used to identify risk factors for increased negative symptoms among contraceptive users and evaluate the impact of experiencing symptoms on women’s daily activities. A total of 278 participants (106 injectable, 72 implant, 100 non-users) were included for analysis. Compared to pre-initiation, injectable users experienced 28% more symptoms at month 3 (adjusted incident rate ratio (IRR): 1.28, 95% CI: 1.05 – 1.57 p = 0.015), implant users experienced a peak of 41% more symptoms at month 2 (adjusted IRR 1.41, 95% CI: 1.15 – 1.73, p = 0.002), and non-users experienced no changes over a similar time period. Contraceptive users with physically demanding occupations, food insecurity, and a history of recent infection experienced the greatest symptom severity, also associated with negative impacts on women’s activities, including work, chores, and relationships. These findings indicate that reducing the burden of contraceptive side effects requires addressing underlying health stressors and considering the significant impact of side-effects on women’s daily lives, rather than relying solely on dispelling misconceptions.

What is already know on this topic

What this study adds

The design of this study enables us to demonstrate that side-effects are: (1) significant: users report an increase in symptoms after initiating contraception, unlike non-users who do not exhibit such changes; (2) predictable: women experiencing health stressors (nutritional, physical and infectious) prior to initiation report the greatest number and severity of side-effects when using hormonal contraception; (3) disruptive: higher symptom severity is associated with a decreased ability to carry out key daily activities pertaining to work, relationships, and house chores.

How this study might affect research, practice and/or policy

Contraceptive counselling should be sensitive to variation in risk of side-effects and support women with high symptom burdens with management options or method switching, rather than dismissing concerns as misconceptions.

Our findings highlight the need for further research confirming predictive drivers of side-effect experiences to guide counselling and to move towards personalised contraceptive technology development.

The authors have declared no competing interest.

This study was funded by a Wellcome Trust Seed Grant (210211/Z/18/Z) awarded to AA and an Economic and Social Research Council (ESRC) studentship awarded to RS (ES/P000649/1).

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethical approval was obtained from three bodies: the Oxford Tropical Research Ethics Committee (OxTREC) at the University of Oxford (562-18); the College of Health Sciences at Addis Ababa University (069/19/DMIP), and the Oromia Health Bureau (BEFO/HBTF/1-16/239).

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Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

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Anonymised data underlying these analyses will be made available upon reasonable request.