You can expect swollen fingers, ankles, and feet when you’re expecting. But sudden swelling, especially in the hands and face, can be a sign of preeclampsia. That’s dangerously high blood pressure that can happen in the second half of pregnancy. Rarely, it comes after childbirth and is called postpartum preeclampsia. The problem affects the kidneys, triggering swelling. You may also have a bad headache, belly pain, and trouble seeing.