It is possible to get pregnant while breastfeeding. Although breastfeeding does suppress ovulation, it’s not a very reliable form of birth control. If your period resumes — even if you have an irregular period while breastfeeding — you can get pregnant.
What's more, it's actually possible to get pregnant before your period arrives. So if you're not ready to put another bun in the oven just yet, be sure to take proper birth control precautions.
Source: https://www.whattoexpect.com/
