Why can the doctors not always find out the sex of the baby?

Doctors may not always determine the sex of a baby due to factors such as the baby's position during an ultrasound, which can obstruct clear visualization of the genital area. Additionally, the gestational age can affect the clarity of the ultrasound images, making it harder to distinguish between male and female anatomy. In some cases, the presence of certain conditions or anomalies can complicate the identification of sex. As a result, while many cases are straightforward, there are instances where the sex remains uncertain.