How do unborn children wee?

Unborn children, or fetuses, produce urine as a byproduct of kidney function starting around the 12th week of gestation. The urine is released into the amniotic fluid, which surrounds the fetus in the amniotic sac. This process contributes to the volume of amniotic fluid and helps in the development of the fetal kidneys and bladder. The fetus swallows some of the amniotic fluid, further aiding in its growth and development.