Determining Fetal Sex
Using the ultrasound to determine fetal sex is a relatively new technology. The optimal time to determine fetal sex is between 62 to 64 days but in some cases can be determined as early as 59 days and as late as 90 days.
The red arrow points to the genital tubercle in the
male and female fetus.
The ultrasound technician must be able to identify the position of the genital tubercle (cells which will form the clitoris in the female and penis in the male, red arrows in the picture above) relative to the femurs (leg bones), umbilical chord and tail. The genital tubercle forms between the legs and then migrates toward the head in the male or tail in the female. In the male, it migrates to a position near the umbilical chord. In the female, it migrates to a position near the tailhead.
Ultrasound
scan of a male fetus
Ultrasound scan of a
male fetus with sound and outlines
Male fetus |
Female fetus |
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