The past three decades have seen considerable change in the understanding of clinical research methods. There has been an acceptance that randomised controlled trials are the best way of establishing treatment effectiveness and a recognition that, while single studies are useful, pooling knowledge from all available randomised trials is likely to provide the best evidence to guide clinical practice. Advances in methodology have accompanied technological innovations in gynaecology and reproductive medicine, such as assisted reproduction, assessment of male fertility, ovulation induction, and laparoscopic surgery. In particular, high-quality systematic reviews have become important tools enabling evidence-based healthcare decisions and identifying gaps in evidence. The Cochrane Gynaecology and Fertility Group has recently celebrated 20 years of preparing and publishing systematic reviews with a symposium at the University of Oxford. With nearly a thousand authors and over 200 reviews, we are well aware of the need for making research more efficient, accessible and influential. This could be achieved by reducing research waste and addressing outcome reporting bias by developing and implementing core outcome sets.