The Pregnancy Discrimination Act is a law in place to protect pregnant women. This law protects pregnant women from being discriminated against based on their pregnancy, childbirth, or any medical issues related to pregnancy and childbirth.
Although there is a law in place, discrimination does still happen. Keep in mind that the burden of proof still rests with the person filing the complaint. If you feel you've been discriminated against, you'll need to keep careful records and documentation to prove it.