Background: Unintended pregnancy has a huge adverse impact on maternal, child and family
health and wealth. There is an unmet need for contraception globally, with an estimated 40% of
pregnancies unintended worldwide.
Methods: We systematically searched PubMed and specialist databases for systematic reviews
addressing contraceptive choice, uptake or use, published in English between 2000 and 2019. Two
reviewers independently selected and appraised reports and synthesised quantitative and qualitative review findings. We mapped emergent themes to a social determinants of health framework
to develop our understanding of the complexities of contraceptive choice and use.
Findings: We found 24 systematic reviews of mostly moderate or high quality. Factors affecting
contraception use are remarkably similar among women in very different cultures and settings globally. Use of contraception is influenced by the perceived likelihood and appeal of pregnancy, and
relationship status. It is influenced by women’s knowledge, beliefs, and perceptions of side effects
and health risks. Male partners have a strong influence, as do peers’ views and experiences, and
families’ expectations. Lack of education and poverty is linked with low contraception use, and
social and cultural norms influence contraception and expectations of family size and timing.
Contraception use also depends upon their availability, the accessibility, confidentiality and costs
of health services, and attitudes, behaviour and skills of health practitioners.
Interpretation: Contraception has remarkably far-reaching benefits and is highly cost-effective.
However, women worldwide lack sufficient knowledge, capability and opportunity to make reproductive choices, and health care systems often fail to provide access and informed choice
