Early prenatal diagnosis of recurrent 46,XY partial gonadal dysgenesis

We present a case of early prenatal diagnosis of recurrent 46,XY partial gonadal dysgenesis, by combining early genetic and sonographic evaluations.

The conceptus of a mother with a first child affected by 46,XY gonadal dysgenesis was sonographically evaluated at 21- and 23-mm BPD (12(+2) and 12(+6) LMP-based age) and the female genitalia were observed. Karyotype analyses was performed on amniotic fluid and it revealed a 46,XY complement without mosaicism. SRY was amplified by PCR for molecular analyses.

We observed a discordance between female phenotype detected at 21 and 23 mm of biparietal diameter (12(+2) and 12(+6) LMP-based age) and male karyotype. In the child and the fetus, seminiferous cords were not recognisable, whereas rare Leydig cells and no germ cells could be identified. Internal and external genitalia were sexually ambiguous in the child and feminized in the fetus.

This is the first case of early prenatal diagnosis of recurrent 46,XY partial gonadal dysgenesis and it points to the importance of combining early analyses of genetic sex with sonography in the management of anomalies of sexual development, with particular regard to syndromes for which the risk of recurrence is little understood.