The Billings ovulation method: data and evaluations from the World Health Organisation multicentre study

Two articles have recently been published reporting the results of a study conducted by the World Health Organisation on the Ovulation Method, which is a natural method of family regulation based on a woman's self-observation of her cervical mucus and its changes during the menstrual cycle, and which allows her to recognise the infertile, potentially fertile, and maximally fertile phases of the cycle.