Unless you meet all of the (very strict) criteria for lactational amenorrhea, then yes!
Lactational amenorrhea (LAM) is defined as the time when a woman does not have a period because she is nursing a baby. If all these criteria are met, it can be considered a time of natural infertility with a pregnancy rate of only around 2 percent. These criteria are:
- Baby is less than 6 months old
- Baby only receives breast milk, no supplements
- Baby feeds at least every four hours during the day and every six hours at night
- No vaginal bleeding after the 56th day postpartum (bleeding before this can be considered normal postpartum bleeding)
Note that if you are pumping, LAM is less effective and would not be recommended as a reliable source of birth control. If you don’t meet all these criteria and don’t want another one on the way, you should talk to your doctor or midwife about birth control options that are safe to use while breastfeeding.