How many days into a pregnancy can a fetus be sexed by ultrasound?

Fetal sexing by ultrasound becomes reliably possible around 55 days of gestation. At this stage, the reproductive structures of the fetus develop sufficiently to be clearly distinguished during an ultrasound examination. Advanced imaging techniques can accurately visualize the genital area and identify whether the fetus is male or female.

Before this time, particularly prior to around 55 days, the reproductive organs are not yet developed enough for consistent and reliable detection, which is why sexing earlier than this can lead to inaccuracies. Consequently, 55 days is recognized as the critical point when accurate fetal sex determination is possible through ultrasound technology.