Menstruation or menses is regular hormonal cycles in women. Some strenuous activity sometimes can not be done, because at the time of menstruation, body condition tends to decrease. For examples: sports, working too hard and swim.
Indeed, there are some women who can do such activities without problems, but for others, such activities will be very painful when it’s done.
When swimming, the blood vessels shrink and make the blood flow is not smooth and reduced. This is because the water temperature tends to be lower than the temperature of the human body.
Women who have to swim during menstruation because of their profession can use pads or tampons that are designed specifically for swimming if it is safe for the body and menstrual health.
The reason why activities such as swimming can be a bit risky for women who are menstruating is due to problems of cleanliness of the pool water. Moreover, other people definitely do not want to swim in contaminated water.
Such as the risk of having sex when a woman is menstruating. Because when menstruation, cervix in the open position and make it vulnerable to infection and endometriosis disease.
So, it does not hurt to wait until menstruation stops, about 5-9 days, then you can return to the activity safely.