Sex During Period: What You Must Know


Keeping a tab on your monthly cycle is crucial- especially if you are planning to conceive (or avoiding it). By tracking your fertility days, you can avoid an unplanned situation. Contrary to the popular notion, there are still chances that you can get pregnant on your period days. It is simply a myth- a woman can’t get pregnant during her periods. The chances are low, but not equal to zero.

Using preventive measures is all well and good. But what if you actually want a pregnancy? Wondering whether it’s possible for you to get pregnant during your days? This article aims to serve that very purpose.[1]

The Process of Conception

From school level biology books, we know pregnancy occurs when an egg meets a sperm inside the uterus or in the fallopian tube of the female. The transfer of male sperm occurs during intercourse. A sperm cell survives in the female uterus for 6 days. During this time, the motile sperm cells have to travel through the cervix and reach the fallopian tubes- to fuse with the female egg and fertilize.[2]

A fertilized egg begins cell division while moving down the fallopian tube- first in 2, then 4, and so on. The fertilized egg reaches the uterus after a week. By this time, it has become a cluster of 100 cells- a Blastocyst.

Ovulation in females

Every month halfway through your menstrual cycle, an egg starts to travel down to the uterus from your ovaries. This egg can survive for 12 hours to 24 hours. This process is known as ovulation.[3]

On average it is the 14th day of the 28-day menstrual cycle. However, the number is not fixed. Some women can have a longer cycle of around thirty-five days. The ovulation is then likely to occur around day 21. Also, women with a shorter cycle of 21 days ovulate around day 7.

The Role of FSH, LH, and Progesterone

FSH(Follicle Stimulating Hormone) is responsible for the maturation of follicles in the female ovary. This occurs between the 6th and the 14th day of the cycle. One fully mature egg cell(ovum) is formed from the follicles by the 14th day. LH(Luteinizing Hormone) levels surge after the 14th day of the menstrual cycle. This forces the ovary to release the egg- which travels through the fallopian tubes to the uterus. The journey usually takes 5 days. The level of progesterone hormone increases, aiding in the preparation of the uterine epithelial walls for pregnancy.[4]

Pregnancy during periods, is it possible?

The chances of getting pregnant are really high if you have sex in the middle of your menstrual cycle. It is a phase that is known as the fertile window. Strangely, the probability of pregnancy before and after this fertile window is really very low- but never zero. There are also several factors for additional consideration.[5]

Here again, time plays a crucial role. Vaginal bleedings are not always a sign of the beginning of the menstrual cycle. Bleeding during ovulation is also a possibility. Considering the period of time sperms can survive, you may get pregnant. Assuming the average ovulation cycle to be within 28 to 30 days- ovulation is distant if you have a sexual encounter during your periods.

The ovulation usually occurs seven to nineteen days after the end of your period. Menstrual cycles are considered “normal” if the period comes every 24–38 days. Hence, it is easy to understand why the cycle length varies significantly between people. The cycle itself varies from person to person.[6]

 In addition, you also need to consider the ability of the male sperm to survive up to 72 hours inside a woman. The probability of pregnancy increases significantly at the end stages of your period. You even can get pregnant if you have sex 3 days before the day of your ovulation. This is why tracking your periods and the number of days in between them is essential. Understanding the pattern is crucial.

Sex during your period: Chances of becoming pregnant

The probability of becoming pregnant can vary throughout your ovulation cycle. Though the average monthly cycle is 29 days, the cycle may vary in females from 20 to even 40 days. It is indeed possible for any woman to get pregnant during their periods. But for those women who have longer cycles, chances of them here are low.[7]

According to experts, the probability of a woman getting pregnant one to two days after she starts bleeding is nearly zero. But then the chances increase again with each passing day. The increase occurs irrespective of the fact that the person is still bleeding. The likelihood of the woman getting pregnant on the 13th day is around 9 percent.

Though the estimated numbers are really low, it doesn’t mean a woman is unable to become pregnant during her period.[8]

Preventive Measures

Having sex on your period won’t likely help you to conceive. The only exception is if your menstrual cycle is less than 28 days. However, there is always a possibility for you to get pregnant.

Preventive contraceptives are the only assured way for you to avoid pregnancy. Contraceptive measures include wearing a condom, taking birth control pills. Birth control pills will not provide protection against sexually transmitted diseases. They are also not helpful in preventing unwanted infections. Ensure that your partner always wears a condom.[9]


Yes, it is possible for a woman to get pregnant during their period- considering all the factors. The chances of becoming pregnant depend on the exact date of the cycle she had sex. Other determining factors include the length of her menstrual cycle and her ovulation period.

Multiple factors make it really difficult to predict the precise timing and extent of the fertility window. Combined with the fact that sperm can remain up to 6 days, the guessing becomes even more difficult. This is why experts always recommend using contraception methods- more so if you are not up for pregnancy. Additionally, people who do wish to get pregnant can keep a note to their fertility and track their ovulation, this can increase your chances of getting pregnant.[10] Observe the pattern of your menstrual cycle in full detail. It is important for both planning and avoiding pregnancy. The cycle is not fixed and is variable from 20 to 40 days. Knowing about the ovulation period is essential to calculate the likelihood of getting pregnant. The probability of getting pregnant is never zero. Therefore, contraceptives are always a better choice- especially a condom. It is also the best way to prevent sexually transmitted diseases and


[2] Filer RB, Wu CH. Coitus during menses.Its effect on endometriosis and pelvic inflammatory disease. J Reprod Med. 1989;34(11):887–890. [PubMed] [Google Scholar]


[4] Bhartiya A. Menstruation, religion and society. International Journal of Social Science and Humanity. 2013;3:523–527. [Google Scholar]

[5] Wagner G, Ottesen B. Vaginal physiology during menstruation. . Ann Intern Med. 1982;96:921–923. [PubMed] [Google Scholar]




[9] Cutler WB, Friedmann E, McCoy NL. Coitus and menstruation in perimenopausal women. J Psychosom Obstet Gynaecol. 1996;17:149–157. [PubMed] [Google Scholar]

[10] Filer RB, Wu CH. Coitus during menses. Its effect on endometriosis and pelvic inflammatory disease. . J Reprod Med. 1989;34:887–890. [PubMed] [Google Scholar]