Can You Only Get Pregnant During Ovulation?

Successfully conceiving often means timing sex so that sperm can reach an egg. There are four phases of the menstrual cycle (menstruation, the follicular phase, ovulation, and the luteal phase), and while they're all important for reproduction, your chances of conceiving differ in each one.

The key player for successful conception is ovulation, which happens when a mature egg has been released from an ovary. The egg lives for approximately 24 hours in the reproductive tract. On the other hand, sperm can live for up to five days under the right conditions. This means that most people can conceive for about six days during each menstrual cycle—the five days before ovulation and one day afterward (called your "fertile window").

So can you get pregnant if you're not ovulating? And what are the chances of conceiving during each phase of the menstrual cycle? Here's what you need to know.

Your Chances of Getting Pregnant During Ovulation

Welcome to the prime time for pregnancy! Your "fertile window" spans from the five days before ovulation to one day afterward. That's because sperm can survive for five days in the reproductive tract, while the egg survives for 24 hours, and it's possible for days-old sperm to fertilize a newly released egg. If you're trying to conceive, it's ideal to have sex multiple times in the days before, during, and just after ovulation.

Given the wide range of cycle lengths (even for the same person), knowing when you ovulate isn't as simple as looking at the calendar or counting cycle days. In fact, it can be nearly impossible to pinpoint exactly when ovulation occurs without an extremely well-timed ultrasound—but thankfully, that level of preciseness isn't necessary to conceive.

Instead, you can try tracking ovulation with at-home methods. "That's where ovulation test kits become so helpful," explains Steven R. Bayer, MD, a reproductive endocrinologist at Boston IVF fertility clinic in Boston. These kits detect a surge in luteinizing hormone (LH) that happens about 36 hours before you ovulate. After the test kit shows a surge, Dr. Bayer recommends having sex in the next 24 to 36 hours. Since sperm can survive for several days in fertile cervical mucus, they will be ready to meet the egg once it's released.

Your body temperature also rises about half a degree (detected by a basal body thermometer) with ovulation, but bear in mind that this increase takes place after you're already ovulating, which could be too late for conception.

Another good indication of fertility is a change in the consistency of your cervical mucus. "You'll see vaginal discharge that increases in amount and has the consistency of egg whites, signaling it's the perfect time to have intercourse," explains Dr. Bayer. You can test your own cervical mucus by sticking your index finger and thumb in your vagina to get a sample, then tapping your finger and thumb together. If the consistency is thin and stretches easily between two fingers, you're good to go.

You can also track fertile days using an ovulation calculator, like the one below.

Your Chances of Getting Pregnant After Ovulation

Also known as the luteal phase, this portion of your cycle begins after ovulation and ends at the start of your next period. During this phase, progesterone starts to rise. Your cervical mucus will dry up, which makes the vaginal tract less friendly to sperm.

Your chances of conceiving when you're no longer ovulating are low. Once the egg has been released, there is a short window of 12 to 24 hours during which it can be fertilized. After that, you will no longer be in your fertile window (unless you happen to release a second egg, which is relatively rare but possible).

If you're looking to avoid pregnancy, this is the phase during which people using fertility awareness methods might have sex freely, but keep in mind that there's never a guarantee when it comes to avoiding pregnancy if a working ovary and sperm are involved.

Your Chances of Getting Pregnant During Your Period

Menstruation is triggered if the released egg hasn't been fertilized—usually somewhere between day 21 and 35 in most people who menstruate. (The first day of your period is considered day one of the cycle.)

During menstruation, the inner membrane of the uterus (known as the endometrium) is shed. By the third day of your cycle, levels of progesterone and estrogen are rising and working to rebuild your endometrium. Around day four, follicle ripening begins to increase as the ovaries start preparing an egg for release.

Most people will ovulate well after their period ends, somewhere around day 14 for the average 28-day cycle—though length and ovulation can vary widely. Because an egg is needed for pregnancy to occur and it's unlikely that an egg will be released around your period, there's little chance that sperm introduced during your period will result in a pregnancy.

However, it is possible to get pregnant if you have sex near the very end of your period and you ovulate very soon after your period ends. Remember: Sperm can live up to five days, so if your period ends on day seven, for instance, and you go on to ovulate on day 10, it's possible to get pregnant from sex as early as day five of that cycle. If you're trying to avoid pregnancy, it's still best to use contraception or abstain from unprotected penis-in-vagina sex during this time.

Your Chances of Getting Pregnant Right After Your Period

If you're trying to get pregnant, you'll want to start having sex after your period ends for optimal chances of conceiving, says Kelly Pagidas, MD, a fertility specialist formerly with Women & Infants Center for Reproduction and Infertility in Providence, Rhode Island. "I recommend having sex frequently—two to three times a week, but every other day if you can—shortly after you stop menstruating to cover your window of pre-ovulation," she explains.

Remember, you can get pregnant right after your period, even if you're not yet ovulating. That's because sperm can live up to five days if it's trapped in fertile cervical mucus—so introducing sperm in the days leading up to ovulation can increase your chances of conceiving.

How Long Pregnancy Really Takes

It can take time to get pregnant—even if you get the timing just right. According to the American College of Obstetricians and Gynecologists (ACOG), menstruating individuals in their 20s and early 30s have a 25% chance of getting pregnant while trying during the average cycle. By age 40, that number changes to a 10% chance.

Research indicates that most people aiming to get pregnant will successfully conceive within the first year of trying. However, many different factors are involved in getting pregnant, from age to medical conditions to fertility issues with either partner. If you have concerns, consult a health care provider or fertility specialist, who can talk to you about your situation and work on optimizing your chances of getting pregnant.