is it normal not to menstruate when breastfeeding? Dr suggested it wasn't

[arolf]

had GP check up this week and was asked if my periods have returned. they haven't. DS is nearly 11 vweeks old and bf. Dr expressed surprise and asked me to go back in 4 weeks time for another check up. my friend had a similar response from her (different) GP - her baby is 1 week younger than mine and also bf.

I thought this was totally normal when bfeeding? am I totally misled? should I worry?

Want to add -- LAM can work, but if avoiding pregnancy is a very high priority, back it up with some other form of contraception every time while you're not TTC.