Objective: To describe the detection of cleft lip in the early second trimester using transvaginal sonography.
Methods: We analyzed retrospectively 14,988 ultrasound examinations conducted for fetal malformations between 12-16 weeks' gestation. Seventy-five percent of the patients were at low risk for fetal anomalies and 25% were at high risk.
Results: Eleven cases of fetal cleft lip with or without cleft palate were detected by transvaginal sonography among 14,988 fetuses (0.07%). In nine cases, no risk factors for cleft lip or palate existed. In six cases, the cleft lip represented an isolated malformation, with no other associated anomaly; in five of these six cases, the pregnancy was terminated. One additional case of a small cleft lip was not detected, for a false-negative rate of 8%.
Conclusions: The fetal lips can be scanned by transvaginal sonography in the early second trimester, and fetal cleft lip can be detected in most cases. Early second-trimester detection of cleft lip by transvaginal sonography allows informed parental choice regarding continuing or terminating the affected pregnancy.