Question

why do girls have their menstrual cycle monthly​

Answer 1

Answer:

When a girl reaches puberty at the age of about 10-12 year, the sex hormones released into her blood cause some of the ova. In her ovaries to become mature.

It is monthly because Usually one mature ovum is released from the ovary into the oviduct once every 28 day's this is called ovulation....

Explanation:

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