Everyone needs oxygen, including a fetus in its mother's womb. Oxygen is vital to life, and to a fetus it is vital to growth and development, so any lack of oxygen has the potential to be devastating and even fatal to a growing fetus. It is therefore important for an expectant mother to avoid any behavior that could reduce the amount of oxygen her baby receives.
How a Fetus Receives Oxygen
Humans do not begin using their lungs to bring oxygen into the body until after birth; in fact, fetal lungs are filled with fluid. In the womb, a fetus receives oxygen from its mother through the placenta and umbilical cord. The mother's oxygenated blood flows in and out of the fetus through veins in the umbilical cord. In cases where this flow is impeded, the fetus will not receive enough oxygen to develop properly.
Why a Fetus Could Lack Oxygen
The most common reason a fetus doesn't receive enough oxygen in the womb is a condition called placental abruption. This condition occurs when the placenta detaches, either partially or fully, from the wall of the uterus, which decreases the blood flow reaching the fetus. Exposure to cigarette smoke directly or secondhand can also impede blood flow to the fetus, as can cocaine use. This lack of blood flow and therefore oxygen can cause permanent damage to the fetus.
Cerebral palsy is one of the most common results of a fetus lacking oxygen in the womb. Cerebral palsy is caused by brain damage that affects the parts of the brain involved in controlling movement and coordination. A child who suffers from cerebral palsy will have trouble with motor skills and balance, and also often will have some form of developmental delay. Treatment involves physical therapy, the use of braces or casts and even surgery in some cases.
A study at the University of Cambridge showed that a persistent lack of oxygen in utero can sometimes lead to heart disease later in life. Dr. Dino Giussan, who led the study, believes this occurs because depleted oxygen levels affect the development of the heart and cardiovascular system. While it might not be immediately apparent that these systems have not developed properly, an adult who lacked oxygen in the womb is at higher risk for heart disease.
Stillbirth means the death of a fetus anytime after 20 weeks of pregnancy. According to the March of Dimes, stillbirths happen in about 1 in 160 pregnancies. About a quarter of stillbirths are caused by problems with the placenta that affect the amount of oxygen that reaches the fetus. If the placental problem is not resolved or the baby is not delivered, the fetus can die from lack of oxygen.