India introduces the series to oestrogen, the hormone of sass, sex and energy. Dr Jackie Maybin explains the role of oestrogen in preparing the body for ovulation and Dr. Sarah Hill explains her research on the effect of oestrogen on the brain. Maisie Hill also pops in with some tips for Spring.Credits:Presented by: India Rakusen.Producer: Ellie Sans.Assistant Producer:Jorja McAndrew.Executive producer: Suzy Grant.Original music composed and performed by Rebekah Reid.Sound design by Olga Reed.Special thanks to all contributors and audio diarists.A Listen Production for Radio 4 and BBC Sounds.