Periodos

Period myths and facts

Revisado: 4 de octubre de 2026

Solo en inglés por ahora

Many things people hear about periods are not true. Here are some common myths about cycles, blood, pregnancy, tampons and exercise, and what health sources say.

Myth: every cycle is 28 days

Fact: 28 days is only an average. Many people have a period about every 28 days, but it is common to have them more or less often. Most adult cycles last somewhere between about 21 and 38 days. It is also normal for the length to change a little from one month to the next.

Myth: you lose a lot of blood

Fact: period blood can seem like a lot, but the total over a whole period is usually only a few tablespoons. A typical amount is about 20 to 90 ml, roughly 1 to 5 tablespoons. Some people do bleed more heavily than this. If your periods feel very heavy or get in the way of your life, it is worth talking to a doctor or nurse.

Myth: you cannot get pregnant on your period

Fact: pregnancy is possible from sex at any point in your cycle, including during a period. Sperm can survive inside the body for up to 7 days after sex. An ovary usually releases an egg (ovulation) around 2 weeks before the next period, but the timing can vary, and sometimes it comes soon after a period ends. Some people also have light bleeding around ovulation and mistake it for a period. If you do not want to get pregnant, use contraception every time. Only condoms also protect against STIs, and some STIs can spread more easily during a period.

Myth: a tampon can get lost

Fact: a tampon cannot get lost inside you. The top of the vagina ends at the cervix (the neck of the womb), and the tiny opening in the cervix is far too small for a tampon to get through. The tampon stays in the vagina until you take it out. It can be forgotten, though. If you cannot find or reach it, or you notice an unpleasant discharge, see a doctor or nurse soon.

Myth: tampons affect virginity

Fact: using a tampon does not affect virginity. A tampon can sometimes stretch the thin tissue at the opening of the vagina (hymen), but that is not the same as having sex. Anyone who has periods can use tampons, and a slim size can be easier at first.

Myth: you should not swim or do sport

Fact: having your period does not mean you need to sit things out. You can keep exercising, playing sport and doing the things you enjoy. For swimming and sport, many people find tampons more convenient than pads. You can choose what feels right for your body on each day of your period.

This is general information. If you have a question about your own periods, a doctor or nurse can help.