Prenatal Findings in Postnatal Cases of Disorders of Sex Development: Experience from a Tertiary-Specialized Center in Brazil.

Introduction and objective: Prenatal suspicion of disorders/differences of sex development (DSDs) is a relatively new phenomenon. The aim of this study was to review the prenatal findings of DSD cases postnatally diagnosed in our tertiary referral center.

Methods: We evaluated 57 DSD cases with sex ambiguity who had undergone prenatal ultrasound with phenotypic sex assessment and/or cell-free fetal DNA (cffDNA) for genotypic sex assessment.

Results: Prenatal cffDNA had been performed in 32 cases, being positive (suggestive of male genotypic sex) in 26 and negative (suggestive of female genotypic sex) in 6. Five with cffDNA negative had a prenatal ultrasound indicating female external genitalia, in turn, in those with cffDNA positive, only two had a prenatal ultrasound indicating male external genitalia. Our postnatal data showed that when external genitalia were female or poorly virilized, prenatal ultrasound indicated female sex, but in cases of higher degree of virilization, ultrasound showed similar rates of male, female, or undetermined sex. Regarding the karyotype, our data showed those with XY karyotype had positive cffDNA, those with XX karyotype had negative cffDNA, and all five with sex chromosome anomalies had positive cffDNA because they were 45,X/46,XY. We suggested an algorithm to investigate these cases during gestation, including evaluation of uterus, fetal growth, and malformations.

Conclusion: We suggest that the parents should be counseled prenatally by a dedicated multidisciplinary team with experience in DSD management and evaluated as soon as possible after birth.