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Q: When can a woman going through menopause stop worrying about birth control?
A: Menopause “officially” occurs 12 months after a woman’s last menstrual period — a diagnosis that can only be made after the fact. It is when a woman’s fertility permanently ends, and usually occurs in the 40s or 50s; the average age in the US is 51. The years leading up to menopause are a time when fertility drops sharply and periods continue but become less frequent and more irregular.