Your Baby's Development
Although your baby is still receiving oxygen through the placenta, once birth occurs his or her lungs will start taking in oxygen on their own. In preparation for the outside world, your baby's lungs will now begin to produce surfactant. Surfactant is a substance that keeps the air sacs in our lungs from collapsing and sticking together when we exhale, allowing us to breathe properly.

Because the inner ear is now completely developed, your baby may be able to tell when he or she is upside down or right side up while floating and making movements in the amniotic fluid. The inner ear controls balance in the body.

Your Body
An important prenatal test, the glucose screening, is usually performed sometime during weeks 24 to 28. The glucose screening checks for gestational diabetes, a temporary type of diabetes that occurs during pregnancy and can cause newborn problems such as low blood sugar. Gestational diabetes may also increase the chances that a woman would need a cesarean section because it can lead to the hormonal growth of unusually large babies (macrosomia). During the glucose screening test, you'll drink a sugary solution and then have your blood drawn. If your blood sugar levels are abnormal, you'll have further tests, which your health care provider will discuss with you. Usually gestational diabetes can be controlled with a strict diet (similar to the one a diabetic follows), but sometimes medication, such as daily insulin, will be needed during the course of your pregnancy.