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How is the sex of a fetus determined?

There are a few ways. The traditional way is to do an amniocentesis in which the doctor inserts a long needle through the mother's abdomen and removes some of the fluid from the womb. The baby sheds skin cells each day just as we do. Each cell contains 46 chromosomes and they can be arranged in pairs in a picture. They can then be examined for any defects, etc. The sex chromosomes can also be viewed at this time and if it is a boy it will have an X and a Y. If it is a girl, it will 2 X's. Ultrasound can also be done and if the baby is oriented in the proper way, sometimes the gonads are visible. This method is not foolproof however.

Van Hoeck

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