A CONTROVERSIAL study has found that women can ovulate more than once per cycle, which implies the textbook explanation of female reproduction will have to be rewritten. The study also suggests a possible explanation for why some women reach the menopause early, and why non-identical twins are so common.
Roger Pierson and his team at the University of Saskatchewan in Canada carried out daily ultrasound scans on 63 women for six weeks. The women all had normal menstrual cycles and were aged between 18 and 40. The team analysed the ultrasound images to measure the diameter of every follicle, or…
