This is part of our Fun With Pee series. Funny, curious, and even startling facts and stories about the pee our bodies make.
Many people assume that a baby’s first urination happens when it comes out of the mother’s uterus, and is exposed to the air for the first time. Many babies will pee at birth, however, that is not the first time urine is produced and leaves their tiny little body.
In fact, a baby will pee while still in the womb. You might be astounded to know that the kidney of a fetus is developed well enough at 14 weeks in the uterus, and the baby will start peeing into the amniotic fluid at that time. Pretty impressive considering the baby fetus is only the size of a lemon.