Your period came, so does that mean you can be a little more lax about birth control? After all, you can’t get pregnant while Aunt Flo is around, right?
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It’s not quite that simple, says Ob/Gyn Amy Stephens, MD. She clears up the confusion about fertility and your monthly cycle.
The most fertile time of your cycle, when you are most likely to get pregnant, is when you ovulate, or release an egg, Dr. Stephens explains. That typically happens midway between periods.
So if you have a regular 28-day cycle, Day 1 would be the first day of your period, and you would ovulate around Day 14. “You have the highest chance of getting pregnant during the few days before and after that day,” she says.
But that’s a general guideline and not a rule. “You can definitely get pregnant outside that window,” Dr. Stephens says.
If you have unprotected sex during or right after your period, there is a lower chance of getting pregnant. “But the chances are not zero,” Dr. Stephens stresses.
That’s especially true for women with irregular periods, whose ovulation date is harder to predict. Even women who normally have periods like clockwork can experience an unpredictable cycle as the result of things like stress, hormonal changes, and losing or gaining weight.
Having a shorter-than-average cycle also increases your risk of conceiving during period sex. That’s because sperm can live inside you for up to 5 days. They could still be hanging around, looking for love, if you release an egg 4 or 5 days after your period ends.
How not to get pregnant
If you want to get pregnant, plan to get frisky halfway between periods for the best chances. But if pregnancy is what you’re trying to avoid, there are much, much better methods than using your period as a guide.
“The best way to prevent pregnancy is to use a reliable form of birth control,” Dr. Stephens says.
Yeah, you probably already knew that. But now you know the whole story.