Many women wonder how to avoid pregnancy, given their menstrual cycles and fertile times. It is important to begin by knowing how your cycles work. The menstrual cycle is the time from the first day of your period to the first day of your next period; for most women, that is about 28 days. About 12-14 days before your period begins, you are most fertile. This is when you ovulate, or release an egg. This is when you are most likely to become pregnant. So when is the safe time to have sex? The answer is as complicated and varied as the woman.  Learn the answer below.

When Is the Best Time to Have Sex and Not Get Pregnant?

The best rule of thumb to remember is this: If you are having sex, you can get pregnant. That’s because there is no sure way to know when a woman will ovulate. Though for most women the time of ovulation is right at 12-14 days before they begin their period, some women have different schedules, and are fertile at different times. So figuring out when to have sex to avoid pregnancy can be very difficult, if not impossible.

General Rule

Some women believe that the safe time to have sex is right after their period starts or right before it begins; however, those dates might not be accurate, due to changing schedules and fluctuating hormones. But if you have a regular menstrual cycle lasting around 28 days, 7 days before your period and 7 days right after your period are generally the safe window.

Avoid Your Fertile Days

Another way to know the best time to have sex is to avoid your fertile days, which depends on different cycle length. Here’s the general rule:

One Way to Track and Calculate When You Are Less Likely to Get Pregnant

Step 1

If you want to track the days when you might be most fertile, keep up with your periods for at least six months. Then subtract18 days from the total number of days of your shortest cycle. Once you have that number, you can then count ahead from the first day of your next period. Mark that date on the calendar.

Step 2

Then go back to your longest cycle, and subtract 11 days. Take the resulting number and count ahead from the first day of your next period. Mark that date on the calendar.

Step 3

The days in between the marks are the ones when you are mostly likely to get pregnant. So that means the safe time to have sex is anytime outside of those dates. However, also keep in mind that sperm can live for up to four days, so mark out the days on either side of the “X”, counting four days on each side.

Remember that this only works if you have regular periods that you can easily track!

Notes and Precautions:

  • Keep in mind that even if you do figure out when you ovulate, it can be tough to know exactly when you can and can’t have sex. That’s because some sperm can live in the vagina for four days or even longer.
  • Finally, remember that even having sex during your period might not be a guarantee that you won’t get pregnant. Some women tend to ovulate very quickly, which means you might be at the end of your period when you ovulate – this is especially true if your cycle is irregular.  
  • In conclusion, the safest method is always to use protection while having sex.

To learn much more about ways to avoid pregnancy, as well as more information on best time to have sex and not get pregnant, calculate your estimated date of ovulation here.