It is relatively normal for a fetus to not be able to see the scrotum at 27 weeks of pregnancy. Generally at 27 weeks of pregnancy, since the fetal testicles have not yet descended into the scrotum, it may not be possible to determine the exact location of the scrotum during the examination. The position of the fetus during the examination is also relevant, as the scrotum may not be visible if it is blocked, which is usually normal. The testicles will gradually descend to the scrotum around three months after birth. If the fetus is growing and developing normally during the ultrasound examination, and there are no abnormalities or missing genitals, there is usually no need to be overly nervous. During pregnancy, you need to see your doctor regularly for ultrasound and other checkups to avoid symptoms such as abnormal development of the fetus.