A common myth is that it is impossible to get pregnant while you are menstruating. Typically, getting your period is an almost certain sign that you have not conceived. While it is highly unlikely that you’ll get pregnant on your period, it may very well happen.

If you are planning for a pregnancy, it’s crucial to start keeping tabs on your menstrual cycle so that you can easily track the days when you are most fertile; it is during this time that you are most likely to conceive. On other days of the cycle, while conception is difficult, it is not impossible.

It’s important to remember that each body is different, and the menstrual cycle too is not the same for everyone. The differences are usually with respect to the length of your cycle, the heaviness of the bleeding, the extent of symptoms and so on. As a matter of fact, it is absolutely normal for these parameters to change as you grow older and your body undergoes myriad changes.

This article explores the possibility of getting pregnant while on your period and answers any questions you may have about ovulation, conception and birth control measures during menstruation.  

Everything You Need to Know About Ovulation

On an average, the menstrual cycle lasts for 28 days; the cycle is reset each month when you start bleeding. However, according to research, cycles lasting between 26 to 35 days are common as well.

The menstrual cycle is divided into four phases: Menstruation (or, your period), the follicular phase (when your body is gearing up for a possible pregnancy), ovulation (often referred to as the phase when your body is most fertile) and the luteal phase (when the egg released from the ovary makes its way to the uterus.)

Ovulation is a phase during your menstrual cycle when an egg is released from the ovary. After being released, the egg might end up being fertilized or it might not. If the egg is fertilized by a sperm, it begins its journey to the uterus where after implantation, it develops into a pregnancy. If the egg is not fertilized, then it will disintegrate; the uterine lining, too, is shed by your uterus. This is when you start menstruating.

Ovulation comes after the follicular phase of your menstrual cycle which usually starts the day you get your period and continues till you start ovulating. During this phase, your body produces the follicle-stimulating hormone (FSH) which helps the egg inside your ovary to mature before release. 

Soon after, your body releases the luteinizing hormone (LH) which causes the egg to release. This is around day 14 of your menstrual cycle, and this is when you begin to ovulate. To put it simply, ovulation occurs in the middle of your cycle.This is succeeded by the luteal phase where your body begins to produce progesterone in large quantities. This hormone prepares and equips the uterus for a pregnancy with the uterine lining thickening. Keep track of your ovulation period with our Ovulation Calendar.

What is the “Fertile Window”?

The fertile window is when the egg has been released following which the egg can survive for approximately 12 to 24 hours. During this period, if the egg meets a sperm, it may result in fertilization and eventually, pregnancy.

Medical practitioners use the phrase “fertile window” to refer to five days leading to ovulation, the day of the ovulation and one day after your ovulation.

What are the Chances of Getting Pregnant While on Your Period?

It is not likely that if you have intercourse during your period, you could get pregnant immediately. This is because your body is probably not ovulating yet. Whether you can or cannot get pregnant on your period largely depends on the length of your cycle. On an average, most research suggests that ovulation occurs on day 14 of your menstrual cycle. But a one-size-fits-all policy rarely works. This math only applies if you have a cycle that lasts 28 days. If in a particular month you have a shorter than usual cycle, you could begin to ovulate shortly after your period.

The timing of intercourse plays a major role too. Studies suggest that sperm can survive in the body for up to five days. This means that if you engage in intercourse towards the end of your period, the sperm could survive in your body long enough for you to start ovulating, resulting in a pregnancy.

The truth is, it is medically impossible to determine exactly when a baby was conceived. Only a rough estimate can be offered. By tracking your menstruation dates each month and by observing the patterns and changes in your cycle, you may be able to approximately calculate your fertile window. However, there is no way to be 100% certain.

A study found that the chances of conception begin to dramatically increase about seven days after your last menstrual period (LMP) and reach its peak at around 15 days. You have a 2% chance of being within the fertile window as you enter the fourth day of your cycle. On the twelfth day of your cycle, the same probability is 58%. The study also found that women who are older often tend to get pregnant earlier on in their menstrual cycles.  

Factors Affecting Pregnancy During Your Period

There are several factors which could affect the variability of your menstrual cycle and your health. Some of them are:

• Age

• Ethnicity

• Quality of sleep

• Stress

• Eating habits

• Sudden changes in your weight

• Strenuous exercises

• Obesity and weight gain

• Hormonal birth control and contraception

• Alcohol consumption

• Smoking

• Chronic ailments

• Certain types of medication

Some health conditions could have an impact on your cycle too. These include:

• Polycystic Ovarian Syndrome (PCOS)

• Pelvic Inflammatory Disease

• Eating disorders

• Fibroids in the uterus

• Thyroid conditions

• Endometriosis

Irregularities in your menstrual cycle, which are fairly common, may impact when you ovulate. For instance, if you have started working out recently, or if you have started a new diet, or have been experiencing problems with your sleep and have been under stress, your ovulation may happen earlier or later than usual.

It is also common to experience light bleeding when you begin to ovulate. Ovulation bleeding, as studies show, is generally lighter than a period. For most, it may look like just a few reddish or pinkish drops in your underwear. This may also be referred to as spotting. But this spotting is often mistaken for your period, when it's not. If you have intercourse during this period, having mistaken ovulation bleeding for your period, the chances of you conceiving are higher.

Similarly, some of the most common symptoms of PCOS or endometriosis are irregular periods or even amenorrhea, meaning the absence of a period. With cycles that are difficult to predict, it can be even tougher to track your ovulation days. This increases your chances of conceiving if you have intercourse during menstruation.

What Happens to Your Period if You Get Pregnant?

If you do get pregnant after unprotected intercourse during your period, you are probably not going to menstruate the following month. You may, however, experience some light bleeding or spotting. This is called an implantation bleed. This happens when the fertilized egg gets implanted into the endometrial lining within your uterus. A majority of women experience implantation bleeding, and it is almost never a cause for concern.

Truly, the only way to determine if you’re pregnant is by taking a pregnancy test. You can do that after waiting for a week after you’ve missed your period. Generally, pregnancy symptoms include soreness in your breasts, fatigue, headaches and nausea. It is vital to note that these symptoms are also common during menstruation.

Birth Control Measures During Your Period

In short, you could still get pregnant if you have intercourse while on your period without contraception, even if you are sure of your math. If pregnancy is not on the cards for you, it is advisable to use one of the following methods to avoid conception:

• Barriers: These include diaphragms and condoms and prevent pregnancy by preventing the matured egg from coming into contact with the sperm. A condom can also protect you from a variety of Sexually Transmitted Diseases (STDs) like chlamydia and herpes. Female condoms, which work in the same manner and has to be inserted vaginally, are also becoming increasingly popular.

• Intrauterine Device or IUD: An IUD is planted inside the uterus through the vagina. It prevents pregnancy by regulating the hormone levels of the body.

• Hormonal birth control: These include birth control pills or emergency contraception pills or the morning-after pill. Such forms of birth control contain synthetic hormones in order to prevent unwanted pregnancies.

• Sterilization: This is a permanent solution to prevent pregnancies and include occlusion (female tubal ligation) or vasectomy for males.

Conclusion

There is always a chance you could get pregnant if you have unprotected intercourse. But the possibilities of that happening change, depending on the time of the month and the phase of the menstrual cycle you are in.

For someone whose menstrual cycle lasts 28 days, ovulation is likely to occur on day 14 of your cycle. You become increasingly more fertile leading up to ovulation and remain so a day or two after the egg has been released from the ovary. However, for people with shorter cycles or irregular periods making it difficult to track your cycle, ovulation may happen earlier; in some cases, it may happen soon after menstruation. This automatically increases the chances of your getting pregnant if you have intercourse during your period or immediately after it.

Frequently Asked Questions (FAQs)

1. Can you get pregnant a day before your period starts?

The chances are very low. The probability of you getting pregnant increase as your period ends and your body prepares for ovulation.

2. Can you get pregnant just after your period ends?

You can get pregnant if you engage in intercourse just after your period ends and you are nearing ovulation. This is more likely if you have a short menstrual cycle.

3. When should you take a pregnancy test?

It is better to wait till you have actually missed your period to get tested. You can take a test on the day you missed your period or in the days after. This is when you are likely to get an accurate report. 

4. How to calculate your fertile days?

On an average, your ovulation comes about 12-14 days before your expected date of menstruation. You will be fertile for around 5 days leading to the ovulation phase, the day of ovulation and around one day after. The fertile window is expected to be around 5-7 days.

Sources

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