Sulfatase deficiency in the human placenta: clinical findings

Sulfatase and aromatase are the key enzymes of estrogen biosynthesis in the human placenta. A total of 76 pregnancies with sulfatase deficiency have been reported. Reduced sulfatase activity occurs in 1:2000 of 1:6000 pregnancies. It can be suspected in patients with low urinary excretion or low serum estriol levels. The sulfatase deficiency can be detected during pregnancy by a prolongation of the half-life of dehydroepiandrosterone sulfate (DHAS) after venous DHAS loading (50 or 100 mg). Post partum the placental sulfatase deficiency can be demonstrated in vitro by nonconversion of radioactive DHAS to DHA. Only 7 of the 76 pregnancies described ended with an uncomplicated vaginal delivery after spontaneous onset of labor. A cesarian section was required in 18 cases. The other case reports mostly concern patients associated with a prolonged pregnancy, lack of cervical dilatation, or absent induction of labor. All 76 newborns were male. Sulfatase deficiency is probably a congenital, sex-specific, X-linked placental enzyme defect. A special therapy is not necessary but the antepartum diagnosis is important because this benign disorder has to be discriminated from the more serious fetal adrenal hypoplasia.