For both my babies, my period returned about 4-6 weeks postpartum despite the fact that I breastfeed. It worried me because I had read that when you breastfeed, your period is likely to return only when you wean baby. I thought something was wrong with me. I thought that I was having excessive lochia bleeding. I thought that I was having complications from my caesarean birth. I went to see my doctor and was told that it was probably my period which did nothing to ease my worries because of the word "probably".
I search the internet and was comforted when I read this:
When it comes to menstruation and breastfeeding, just about anything can be considered normal. Some moms get their periods when the baby is two or three months old, even if they are exclusively breastfeeding. Other moms may be partially breastfeeding and not get their cycle back until they wean. It just depends on the mother and how sensitive she is to the hormonal influences of breastfeeding. Read more here.
It worried me, but it does happen, ie the early return of period or menstruation even when breastfeeding exclusively. Read this Q&A: Menstruation: Early return of period with exclusive nursing And no, the return of my period does not affect my milk supply. I'm still breastfeeding my 2 year old and my period still comes regularly.
I hope that this short post helps to ease the worries of some other mums with the same experience.