Period sex can be a divisive matter. For some people it’s a regular part of their sex lives, for others it’s a messy issue.

Women normally are not able to conceive whilst on their period, but sperm survives within the female reproductive system for up to three days. This means some women do have a small chance of becoming pregnant from unprotected sex during their period. It all depends on the length of your menstrual cycle.

Assuming that you have a menstrual cycle shorter than 28 days and you have sex towards the end of your six-day-long period and ovulate shortly after, then there is a chance that some of the sperm survive and you could get pregnant. So, while getting pregnant is unlikely, it’s technically possible if you don’t know your fertile window. There are some things you need to know about fertility and having sex on your period. First you need to know how conception occurs.

The ability to conceive is miraculous. It requires the meeting of a male’s sperm with a female’s egg. Once a woman’s ovary releases an egg, the egg lives for only between 12 and 24 hours. The male sperm can live for about three days.

The typical female cycle is 28 days. Day 1 is when you start your period. Typically, you ovulate around day 14 (but it could be around days 12, 13, or 14). Ovulation is when your ovary releases an egg for fertilisation. If a sperm is available in the uterus, pregnancy can occur. It can vary based on your menstrual cycle.

If you have a longer cycle of around 35 days between periods, ovulation would then happen around day 21. If you have a shorter cycle of 21 days, you would ovulate around day 7.

For the average woman, the menstrual cycle is between 26 and 30 days. This means that if you have sex while on your period, you won’t likely ovulate until several days later.

But women with a shorter cycle wouldn’t have the same amount of time between having their periods and ovulating.

Another consideration is that a man’s sperm can live inside a woman for up to 72 hours after ejaculation. Toward the end of your period, your chances of becoming pregnant will increase.

If you’re curious about your ovulation patterns, you can track the number of days between your periods. This includes when you start your period, and then when you start the next one.

Over several months, you can identify a pattern to determine roughly when your ovulation cycle occurs. While the average female’s monthly cycle may be 29 days, others may have a cycle that varies from 20 to 40 days, or longer.

The likelihood that you will get pregnant one to two days after you start bleeding is nearly zero, but the likelihood starts to increase again with each successive day, even though you’re still bleeding.

At roughly day 13 after starting your period, your chance of pregnancy is an estimated nine per cent.

While these numbers may be low, it doesn’t mean that you can ever be 100 per cent assured that you won’t get pregnant during your period. If you’re trying to get pregnant, having sex on your period won’t likely help you to conceive unless your menstrual cycle is less than 28 days. But it’s always possible that you could become pregnant.

The bottom line is that your ovulation cycles can vary, so it’s statistically possible you could become pregnant while on your period. While pregnancy is less likely in the earlier days of your period, the chances increase in the later days.

If you’re trying to become pregnant and haven’t conceived after a year or more of having unprotected sex, contact your doctor. They can recommend methods of tracking your ovulation, as well as fertility experts. Your doctor can also provide testing and treatments that will help you increase your chances of conception.

It’s very unlikely you will get pregnant in the days immediately before your period. However, women are unique and cycles are not the same and so peak fertility varies. This means for some women the days before menstruation are fertile. Getting pregnant 5 days before your period is a possibility for some women, if they ovulate close to the end of their menstrual cycle, but typically peak fertility occurs earlier in the menstrual cycle.

So now you know it is possible to get pregnant on your period. While many may think it’s gross or messy, having sex on your period is perfectly healthy and lots of women practise it.

Due to a dip in progesterone, you may find your sex drive increases around menstruation. On top of this, orgasms can alleviate period cramps and cause the uterus to contract more, which in the end can mean shorter periods too.

PUNCH.