Babies receive oxygen in the womb through a process called fetal respiration. This occurs in two primary ways:
1. **Placental Exchange**: Oxygen and nutrients are delivered to the fetus through the placenta, a temporary organ that develops during pregnancy. The placenta is attached to the uterine wall and connected to the fetus by the umbilical cord. Oxygen from the mother's bloodstream passes through the placenta and into the fetal bloodstream, where it is carried to the baby's tissues and organs.
2. **Amniotic Fluid**: The fetus also receives a small amount of oxygen from the amniotic fluid surrounding it in the womb. As the baby moves and practices breathing motions, it may swallow small amounts of amniotic fluid, which contains dissolved oxygen. This oxygen helps to oxygenate the fetal lungs and support their development.
It's important to note that while the baby's lungs are present and developing in the womb, they are not used for breathing until after birth. The fetus does not inhale air into its lungs while in the womb; instead, the lungs remain collapsed and fluid-filled until the baby takes its first breath at birth.