Sonographic measurement of corpus spongiosum in male fetuses

Abstract

Objective: To establish a nomogram of the corpus spongiosum dimensions in male fetuses and to evaluate its correlation with penile length. These references can be useful when fetal genital anomalies are suspected, particularly to distinguish micropenis from concealed penis cases.

Method: A cross-sectional prospective study was conducted on 486 fetuses of normal singleton pregnancies between 18 and 40 weeks. Corpus spongiosum length, penile length, penile diameter and scrotal diameter were measured by one operator. All measurements were analyzed according to gestational age.

Results: The four measurements were studied as a function of gestational age. Median values, 3(rd) and 97(th) percentiles were determined using regression curves. A correlation between penile length and corpus spongiosum length (r(2) = 0.845) was observed.

Conclusion: We established measurements of the length of fetal corpus spongiosum and a correlation between the former and the penile length. These references can be useful when fetal genital anomalies are suspected.