Ultrasound-guided fetal skin sampling for prenatal diagnosis of genodermatoses

To evaluate the safety and diagnostic efficacy of ultrasound-guided fetal skin sampling for the prenatal diagnosis of genodermatoses.

Seventeen pregnancies seen over 6.5 years were analyzed retrospectively. Fifteen were at risk for junctional epidermolysis bullosa and two for recessive dystrophic epidermolysis bullosa. Under ultrasound guidance, a biopsy forceps was inserted through a 14-gauge catheter and directed toward the fetus (thorax, back, or buttocks) to obtain skin samples. The procedures were performed at a mean of 18.3 weeks' gestation (range 16.5-19.5).

Fetal skin sampling was successful in all cases; the mean number of biopsies taken was 3.6 (range two to five). Five of the 17 fetuses were determined to be affected, each with junctional epidermolysis bullosa; these pregnancies were terminated electively and the prenatal diagnoses confirmed. The remaining 12 pregnancies resulted in the delivery of healthy infants at or after 37 weeks' gestation. There were no pregnancy-related complications, specifically preterm rupture of the membranes or preterm labor. Three of the 12 infants had minor skin blemishes believed to be due to the skin sampling.

Ultrasound-guided fetal skin sampling is the procedure of choice when fetal skin is required for prenatal diagnosis of genodermatoses.