A female has the previous child with congenital adrenal hyperplasia. In the present pregnancy, steroid therapy should be started –

Recommendations for pregnancies.ar risk of CAH consists of administration of dexamethasone (20 mg/kg). It started by 6 weeks of gestation, this ameliorates the virilization of the external genitalia in affected females chronic villus sampling is then performed to determine the sex and genotype of the fetus; therapy is continued only if the fetus is an affected female. As pregnancy is diagnosed (by urine test) at around 6-8 weeks, so it should be the answer.