PENILE TUMESCENCE IN THE HUMAN FETUS AT TERM - A PRELIMINARY-REPORT

The aim of this study is to reveal whether the penis per se actually b ecomes tumescent and flaccid, in time sequence, in the human fetus at term. We observed the fetal penis with realtime ultrasonography in 50 male human fetuses at 36-39 weeks' gestation and measured the penile l ength once at a given time per 1-min epoch for each case during the 60 -min window of examination. Thirty-eight were excluded due to a lack o f continuous ultrasound visualization of the penis. Penile length chan ges were statistically analyzed for the remaining 12 fetuses using the 'least median of squares regression'. Penile length was seen to be si gnificantly stratified into two groups: 22.5% at tumescence (group med ian = 20.8 mm) and 77.5% at flaccidity (group median = 16.0 mm). Penil e tumescence was found to occur at the following frequency during the given observation period: once in 41.7%, twice in 50.0% and three time s in 8.3% with durations ranging from 5 to 17 min. These findings indi cate penile tumescence exists in the term fetus. The frequency and dur ation of penile tumescence are in good correlation with neonates.