I breastfed my daughter for the last time almost a week ago after 7 months. Has anyone had significant back pain after stopping breastfeeding? My lower back is aching like mad! Alternatively, I started to think I might be pregnant again although haven't had a period yet. I've read that in early days of pregnancy, the hormone relaxin can cause backache which is produced in large amounts. I don't remember having this pain with my first pregnancy however. Anyone else had the same experience after stopping breastfeeding?