Baseline Characteristics of Infants With Atypical Genital Development: Phenotypes, Diagnoses, and Sex of Rearing

PURPOSE: Little is known about the phenotypes, diagnoses, and sex of rearing of infants with atypical genital development in the United States. As part of a multicenter study of these infants, we have provided a baseline report from US difference/disorder of sex development clinics describing the diagnoses, anatomic features, and sex of rearing. We also determined whether consensus guidelines are followed for sex designation in the United States. METHODS: Eligible participants had moderate-to-severe genital atypia, were aged <3 years, and had not undergone previous genitoplasty. Karyotype, genetic diagnosis, difference/disorder of sex development etiology, family history, and sex of rearing were collected. Standardized examinations were performed. RESULTS: Of 92 subjects, the karyotypes were 46,XX for 57%, 46,XY for 34%, and sex chromosome abnormality for 9%. The median age at the baseline evaluation was 8.8 months. Most 46,XX subjects (91%) had congenital adrenal hyperplasia (CAH) and most 46,XY subjects (65%) did not have a known diagnosis. Two individuals with CAH underwent a change in sex of rearing from male to female within 2 weeks of birth. The presence of a uterus and shorter phallic length were associated with female sex of rearing. The most common karyotype and diagnosis was 46,XX with CAH, followed by 46,XY with an unknown diagnosis. Phenotypically, atypical genitalia have been most commonly characterized by abnormal labioscrotal tissue, phallic length, and urethral meatus location. CONCLUSIONS: An increased phallic length was positively associated with rearing male. Among the US centers studied, sex designation followed the Consensus Statement recommendations. Further study is needed to determine whether this results in patient satisfaction.