Each month there is a narrow window for successful conception due to the limited lifespan of the sperm and egg, which begins from around five days before ovulation (egg release) and lasts until several hours afterwards.
The period of a woman’s cycle can be identified by different methods, including urine ovulation tests (dipstick devices that can detect changes in hormones released into the urine, signifying when ovulation will occur), fertility awareness-based methods (FABM) (including calendar tracking, monitoring changes in cervix fluid and body temperature) or identifying when the egg is released on ultrasound. This review aimed to assess the benefits and risks of timed intercourse on pregnancy, live birth, negative effects and quality of life in couples trying to conceive.
Tatjana Gibbons, a DPhil researcher at Oxford’s Nuffield Department of Women's & Reproductive Health and lead author on the study, said: ‘‘Many couples find it difficult to achieve a pregnancy, which can lead to concerns about their fertility.'
Professor Christian M Becker of the Nuffield Department of Women's & Reproductive Health said: ‘The high threshold of evidence required in a Cochrane review makes even this moderate quality evidence for the effectiveness of urine ovulation tests quite impressive, as well as surprising considering how long they have been available for.’