Can You Get Pregnant Right After Your Period?

You might have heard that you can't get pregnant right after your period. But in reality, people sometimes can conceive by having penis-in-vagina (PIV) sex immediately following menstruation. Read on to learn what experts say about your chances of getting pregnant right after your period.

Your Menstrual Cycle and Conception

Your menstrual cycle has four phases: menstruation, the follicular phase, ovulation, and the luteal phase. While each phase is important for reproduction, pregnancy relies heavily on the ovulatory phase; that's when a mature egg is released from an ovary and travels down the fallopian tube.

The egg that's released during ovulation survives for only 24 hours. Sperm, on the other hand, can survive three to five days in reproductive tract under the right circumstances, says Barbara Stegmann, M.D., a triple board-certified OB-GYN and women's health clinical lead at Organon, a global health care company. So having PIV sex during ovulation or the days beforehand can result in pregnancy since the egg can meet with existing sperm in the reproductive tract.

But "if the egg is not fertilized by a sperm during this time, it does not survive," says Michele Hakakha, M.D., a board-certified obstetrician and gynecologist based in Los Angeles and co-author of Expecting 411: Clear Answers and Smart Advice for Your Pregnancy. About 12 to 16 days later, your uterine lining sheds, resulting in your period.

So when exactly is ovulation? It tends to occur 14 days prior to your next period. For example, people with 28-day cycles typically ovulate on approximately day 14 of their cycle, explains Lauren Sundheimer, M.D., MS, FACOG, an OB-GYN practicing in Orange County, California. Those with 30-day cycles ovulate around day 16. (Day one is considered the first day of your period).

It's important to note, though, that cycle length varies from person to person and even cycle to cycle. This variation can make predicting ovulation especially tricky if you have irregular cycles, since you don't know when your next period will arrive.

Getting Pregnant Right After Your Period

For most people, pregnancy isn't likely to happen right after your period—but it is possible. As early as the third day of your menstrual cycle, your levels of the reproductive hormones progesterone and estrogen, which taper off at the start of your period, begin to climb and help your uterine lining rebuild.

Here are a few scenarios that can lead to conception immediately after menstruation.

You have a short menstrual cycle

Although an egg doesn't typically release during the immediate post-period phase, called pre-ovulation, your chances of conceiving aren't zero. Sperm can live up to five days in fertile cervical mucus. That means they can stick around for a few days until your body does release an egg during ovulation. If you have a short menstrual cycle, you may be fertile soon after your period ends.

For example, if you ovulate on day 11, it is technically possible to get pregnant from sex as early as day six of that cycle, which may be right after your period ended. "One study showed that people who had sex only one time during this phase still got pregnant," says Steven R. Bayer, M.D., a Boston-based reproductive endocrinologist.

In fact, a 2018 study in Obstetrics and Gynecology examined PIV intercourse patterns in people trying to conceive with the help of ovulation tests. Researchers found an increased pregnancy likelihood in the days leading up to ovulation—18.5% for day one and 23.6% for day two.

You miscounted cycle days

You can also get pregnant if you miscounted cycle days and mistakenly had unprotected PIV sex near ovulation. To determine day one of your menstrual cycle, start counting on the first day of red blood rather than at the end of your menstrual period, says Dr. Sundheimer.

"The duration of bleeding for a period also varies, so when you're counting time to ovulation, it's better to count from the first day of a period rather than days since bleeding stops." Doing so can prevent you from having sex too close to ovulation, which can lead to pregnancy.

Your period bleeding lasts a long time

It's not uncommon to have spotting in the day or so before your period starts and for a few days after that. Because of this bleeding, you might falsely believe you're still on your period and can't get pregnant. In reality, though, ovulation can be closer than you think.

Managing Fertility After Your Period

You don't want to worry about getting pregnant before you're ready. That's why it's essential to know your cycle and use protection whenever there's a chance you could get pregnant. Having a birth control plan (and possibly a back-up plan) in place is especially important when you're actively trying to avoid pregnancy.

If you had unprotected PIV sex around your period and are concerned that you may be expecting, look out for early pregnancy symptoms like mild lower abdominal cramping, breast tenderness, and moodiness. Other common pregnancy symptoms will manifest closer to six or seven weeks of gestation, including nausea, vomiting, and fatigue.