Who actually determines the baby's gender? 👶🧬 #ScienceFacts #Pregnancy

[00:00:00]Human life [music] begins when a sperm cell fertilizes an egg, forming a zygote that contains a complete set of [music] genetic information from both parents.

[00:00:08]As the first cell divides and develops, the baby's biological sex has already [music] been determined.

[00:00:14]Because women always contribute an X chromosome, while men contribute either X or Y, it is the sperm that determines [music] whether the baby will be female XX or male XY.