Most cases of cleft lip and cleft palate are noticed right away at birth and don't require special tests for diagnosis. Increasingly, cleft lip and cleft palate are seen on ultrasound before the baby is born.
Ultrasound before birth
A prenatal ultrasound is a test that uses sound waves to create pictures of the developing fetus. When analyzing the pictures, a doctor may detect a difference in the facial structures.
Cleft lip may be detected with ultrasound beginning around the 13th week of pregnancy. As the fetus continues developing, it may be easier to accurately diagnose a cleft lip. Cleft palate that occurs alone is more difficult to see using ultrasound.
If prenatal ultrasound shows a cleft, your doctor may offer a procedure to take a sample of amniotic fluid from your uterus (amniocentesis). The fluid test may indicate that the fetus has inherited a genetic syndrome that may cause other birth defects. However, most often the cause of cleft lip and cleft palate is unknown.