Meconium aspiration happens when a newborn breathes in a mixture of meconium and amniotic fluid. Amniotic fluid is the liquid that surrounds the baby in the womb. Meconium is the baby's first stool, or poop, which is sticky, thick, and dark green. It is typically passed in the womb during early pregnancy and again in the first few days after birth.

Large for gestational age is used to describe newborn babies who weigh more than the usual amount for the number of weeks of pregnancy. Babies are called large for gestational age if they weigh more than 9 in 10 babies of the same gestational age.

A biophysical profile is a test that is sometimes used during the third trimester of pregnancy. It is often done if there is a question about the baby’s health. This may be because of other test results or certain pregnancy symptoms, or because your pregnancy is high risk.

Microcephaly is a condition where a baby's head is much smaller than normal. It is most often present at birth (congenital). Most children with microcephaly also have a small brain and an intellectual disability. Some children with small heads have normal intelligence.

A mother with HIV can pass the virus to her baby during pregnancy, labor and delivery, and breastfeeding.

Premature and low-birth-weight babies may be too immature to regulate their own temperature, even in a warm environment. Read on to learn how to safely keep them warm.

Transient tachypnea of the newborn is a mild breathing problem. It affects babies during the first hours of life. Transient means it is short-lived. Tachypnea means fast breathing rate. The problem often goes away on its own in about 3 days.

Thrombocytopenia means that a newborn baby has too few platelets in their blood. Platelets are blood cells that help the blood clot. They are made in the bone marrow.

Babies in the newborn intensive care unit (NICU) undergo regular testing so they get the important care they need. Here are several common lab tests. Ask your baby's healthcare provider about them.

A baby with hydrocephalus has extra fluid around the brain. This fluid is called cerebrospinal fluid (CSF). Too much CSF can increase the pressure in your baby’s head. This causes the bones in your baby’s skull to expand and separate. The baby's head may look larger than normal.