Has the Era of Individualized Intrauterine Treatment for Congenital Adrenal Hyperplasia Arrived?

ABSTRACT Background Congenital adrenal hyperplasia (CAH) is a common metabolic genetic disease. Early diagnosis and intervention are crucial to improve the prognosis. Noninvasive prenatal diagnosis (NIPD) is an early, safe, and accurate method. This study aimed to evaluate the NIPD of CAH while guiding individualized intrauterine treatment. Methods Twenty families with a 25% risk of having a baby with 21‐hydroxylase deficiency (21‐OHD) were included. Haplotypes were constructed based on targeted sequencing and family linkage analysis. Relative haplotype dosage (RHDO) combined with Bayes factor was used to infer fetal genotypes. Invasive prenatal diagnosis was performed to verify the reliability of NIPD. For affected‐female fetuses, intrauterine treatment was applied until delivery. Results In 20 families, NIPD successfully identified one female‐affected fetus, four male‐affected fetuses, nine heterozygotes, and five normal fetuses. The first‐pass success rate of NIPD was 90% (18/20), the reporting rate was 95% (19/20), and the accuracy was 100% (19/19). Individualized intrauterine treatment avoided 88.9% (8/9) of unnecessary treatment of unaffected female fetuses. Moreover, no significant virilization was observed in the newborn of CAH16, which underwent intrauterine treatment. Conclusion NIPD has far‐reaching implications for the early treatment and clinical management of pregnancy in families with 21‐OHD.