The science of baby making

Professor Joyce Harper (UCL EGA Institute for Women's Health) discusses the science of baby making. She said: “The egg, when it is first ovulated from the woman’s ovary, has actually got a squidgy frame around it, a cytoplasmic shell. Once one sperm has got through, it hardens”.

Listen: BBC Radio 4 ‘Infinite Monkey Cage’ (from 1 min, 11 sec)