During your reproductive years, you will get a period roughly once a month. It's safe for both partners. Having sex on your period is entirely safe, although it can sometimes get messy. However, like everything else involving your period, you need to get prepared.
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The rhythm method, also called the calendar method or the calendar rhythm method, is a form of natural family planning. To use the rhythm method, you track your menstrual history to predict when you'll ovulate. This helps you determine when you're most likely to conceive. If you're hoping to get pregnant, you can use the rhythm method to determine the best days to have sex. Similarly, if you're hoping to avoid pregnancy, you can use the rhythm method to determine which days to avoid unprotected sex. Using the rhythm method for birth control requires careful record keeping and persistence.
A Guide to Period Sex and Why You Should Do It (Literally)
Before your periods stop altogether, it is likely that your periods will become irregular and unpredictable. The time of menopause varies tremendously between women. Although you are less likely to produce an egg ovulate every month, your ovaries will still be producing some eggs and, for this reason, it is important that you consider using contraception. So, although there is a natural decline in your fertility after the age of about 37 years, effective contraception is still required to prevent an unplanned pregnancy. Most women will no longer be fertile by the age of 55 years.