India sits down with her husband Mark to talk about the cycle and their relationship. They also meet a couple - Bill and Amy - who tailor their life based around Amy’s cycle. India and Mark try to decide if this sort of lifestyle is for them.

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 Charlie Brandon-King.

Special thanks to all contributors and audio diarists.

A Listen production for BBC Radio 4 and BBC Sounds.