Can you get pregnant during your period?

Yes — it is possible to get pregnant during your period, although statistically it is less likely. This results from the biology of the menstrual cycle: for most women, ovulation usually occurs several days after the bleeding ends, which reduces the chances of fertilisation during menstruation.

However, this does not mean that the risk is zero. Sperm can survive in the female reproductive tract for up to five days. Therefore, in the case of early ovulation, or long periods — especially in women with short or irregular cycles — fertilisation may occur even if intercourse took place during your period. If you have a 21-day cycle, meaning it is 21 days between day 1 of one period and day one of the next, you are likely to ovulate on day 7 of your cycle. If your period also happens to last 7 days, then you are actually ovulating while still bleeding. So, if you had unprotected sex within the previous five days there is a risk of pregnancy. Add to this, the menstrual cycle is not always perfectly regular — stress, illness, or hormonal changes can shift ovulation.

The menstrual cycle is the monthly hormone driven process that prepares you for pregnancy, whether or not you are trying to conceive! a physiological effect of cyclical hormonal changes that regulate a woman’s ability to conceive. Day one of your menstrual cycle is day one of your period and the cycle runs through until the your next period starts. It is divided into different phases, using a 28-day cycle as an example:

• Menstruation (Approx days 1-5) - the lining of the womb is shed as your period.
• Follicular phase (approx. days 1-14) - Oestrogen levels rise and ovarian follicles in the ovaries mature, the lining of the womb begins to build back up.
• Ovulation (approx. day 14)– a mature egg is released
• Luteal phase (approx. days 14-28) - progesterone levels rise maturing the lining of the womb for possible implantation; if fertilisation does not occur, hormone levels fall and the cycle starts again.

From a fertility perspective, the highest chances of conception occur immediately around ovulation, which makes understanding one’s own cycle crucial both for planning and preventing pregnancy.

Ovulation is a crucial point in the menstrual cycle because it is when fertilisation becomes possible. In practice, fertility is not limited to a single day but rather there is the so-called fertile window which spans several days. This is due to the different lifespans of reproductive cells:

• an egg survives for about 24 hours;
• sperm can retain fertilising ability for up to 5 days.

The timing of ovulation varies and is related to the length of your cycle. Ovulation occurs 14 days before your period starts, therefore,

• if your cycle is 21-24 days, ovulation may occur as early as days 6–9 of the cycle, sometimes even during the final days of your period;
• but if your cycle is 32-35 days long, ovulation may shift to days 18–21 of the cycle

All of which is normal!

Sperm can survive for up to five days inside the female body which explains why conception can occur even if ovulation does not happen on the day of intercourse. If intercourse occurs at the end of menstruation and ovulation follows a few days later, sperm may still be present and active when the egg is released. This is particularly important for women with short or irregular cycles, in whom fertile days may begin earlier than a calendar would suggest.

Although pregnancy during menstruation is rare, certain scenarios can increase the risk of conception. The most likely scenarios include:

• short menstrual cycles (e.g., 21 days) – ovulation may occur very early, sometimes only a few days after bleeding ends or even during its final phase;
• irregular periods – unpredictable ovulation increases the risk of fertilisation on seemingly less fertile” days;

bleeding mistaken for a period –; any bleeding in between your periods or after sex needs to be checked out with your doctor but can confuse you in terms of whether or not it is a period.

Read also: What Causes Irregular Periods?

You cannot have a true period during pregnancy as pregnancy suppresses ovulation and the shedding of the endometrium, which is what usually leads to your period However, especially in early pregnancy, spotting or bleeding may occur and be mistaken for a period.

If your bleeding seems unusual it is important to be checked out.

There are various different forms of contraception which can not only prevent pregnancy but also sexually transmitted infections. These include condoms, hormonal contraception I the forms of pills, patches and rings, progesterone injections and implants, and intrauterine devices, also called coils which can contain both the hormone progesterone, or be non hormonal and contain copper. The only forms of contraception to effectively prevent sexually transmitted infections are the male and female condoms. Contraception needs to be used EVERY time you have sex, , regardless of the day of the cycle.

Natural family planning methods based on cycle observation, body temperature, or cervical mucus. When taught and used correctly, fertility awareness methods are between 91% and 99% effective at preventing pregnancy, but if instructions are not followed exactly only 76% effective, meaning that 24 in 100 women will get pregnant when tracking their fertility for a year. Menstrual tracking apps may help in understanding your own cycle.

Conceiving during menstruation is absolutely not impossible which is why understanding your own cycle and making informed contraceptive decisions are essential.

Your GP, or local family planning clinic will be able to discuss and provide contraception. If you do have unprotected sexual intercourse, emergency contraception is available in the UK from pharmacies and your GP.