If you’re trying to get pregnant, you know step one: Have unprotected sex. But what about what to do after sex to conceive—is there any truth to the idea that just lying there, hips elevated post-orgasm, will increase the chances of sperm meeting egg? And if not, is there something else you should be doing to increase your chances of conceiving instead?
To help ease the frustration that can be part of baby-making, we asked gynecologists and fertility specialists to break down the process of getting pregnant and explain how what you do immediately after sex might impact your chances of conception.
Our experts:
- Asima Ahmad, MD, board-certified ob-gyn, reproductive endocrinologist, and fertility expert, chief medical officer and cofounder of Carrot Fertility in Chicago
- Mary Jane Minkin, MD, ob-gyn, clinical professor of obstetrics, gynecology, and reproductive sciences at Yale School of Medicine in New Haven, Connecticut
- Michelle Montville, MD, board-certified ob-gyn at HerMD in Franklin, Tennessee
- Emmanuelle Bagdasarian, MD, ob-gyn at Good Samaritan Medical Center in the Palm Beach Health Network in Palm Beach, Florida
How long does conception take?
First, a little refresher on how one gets pregnant in the first place. The basics: When a heterosexual couple has intercourse without contraception, the male partner ejaculates and semen is deposited into the vagina. “Semen is a mixture of fluid, special enzymes, and sperm. The sperm release from the fluid after ejaculation, swim through the cervix (where you get your Pap smear), into the uterus, and up into the fallopian tubes,” explains Michelle Montville, MD, board-certified ob-gyn at HerMD in Franklin, Tennessee. “Scientists think it takes about 30 to 45 minutes for the sperm to make that long trip.”
Sperm is of course only one piece of the puzzle, as you also need ovulation to occur. To bring it back to health class again, ovulation occurs when the female partner’s ovary releases a mature egg into the fallopian tube, which is where fertilization typically takes place. “Ovulation may or may not have occurred prior to intercourse, but if it has, the egg may already be in the fallopian tube ready for fertilization,” says Asima Ahmad, MD, a board-certified ob-gyn and reproductive endocrinologist and fertility expert who is chief medical officer and cofounder of Carrot Fertility in Chicago.
It doesn’t technically matter if the sperm or the egg arrives first. “Sperm can present within the fallopian tube within minutes, but they can also survive inside the female reproductive tract for three to five days,” Dr. Ahmad explains. However, “ideally, sperm should be present before ovulation,” she says—as soon as the mature egg is released from the ovary, the fertile window begins to close. “The egg can only be fertilized within 12 to 24 hours after ovulation,” says Emmanuelle Bagdasarian, MD, ob-gyn at Good Samaritan Medical Center in the Palm Beach Health Network in Palm Beach, Florida. (This is why knowing your fertile days and when you are ovulating matters—more on that below.)
If timing aligns and egg and sperm meet, it’s time for fertilization, baby. “The sperm actually binds to the egg and then burrows down through a shell around the egg,” explains Dr. Montville. “The fertilized egg, now called a zygote, then continues the journey to the uterine cavity, where it has to implant into the lining of the uterus, called the endometrium. If implantation is successful, a pregnancy begins to grow.”
How long after sex does implantation occur? On average, the time from fertilization until the mature embryo can implant in the uterine cavity is five to six days, says Dr. Montville.
What to do after sex to conceive
Since getting pregnant requires the presence of some swimmers who’ve made it to the fallopian tubes, it seems logical that keeping sperm around as long as possible by lying down after sex could increase your chances of conceiving, right? Well…
“Despite popular myths, lying down after sex does not increase the chances of pregnancy,” says Dr. Bagdasarian.
In a study published in 2016, nearly 500 women went through intrauterine insemination (where doctors inject sperm directly into the uterus to increase the odds you’ll get pregnant). Researchers had the groups either go on a short bed rest of 15 minutes immediately after the procedure, or get up and move around right after.
Scientists discovered that there was pretty much no difference in the odds of getting pregnant between the two groups. In fact, the women who got up and moved around right away got pregnant 40% of the time, while the bed-rest group got pregnant 32% of the time.
Of course, the study looked at intrauterine insemination and not at couples who had “regular” sex. So do the findings translate? Mary Jane Minkin, MD, an ob-gyn and clinical professor of obstetrics, gynecology, and reproductive sciences at Yale School of Medicine, says yes.
“With women having regular intercourse, the ejaculate goes right up against the cervix,” she explains. “And at your fertile time, the mucus is quite receptive to sperm right there.” The fastest and healthiest sperm go right into your cervical mucus “instantaneously,” she says, making pretty much zero difference whether you lie there for a while after sex or get up and move.
On top of that, while sperm count varies, “there are typically millions of sperm present in the total ejaculate,” says Dr. Montville. “Typical semen ejaculate has at least 15 million sperm cells per milliliter. So even though some semen may come out after sex of the body, there are still plenty of sperm cells that can enter the uterus.”
At the same time, though lying down after sex before you get up to pee won’t hurt your chances of getting pregnant, it may actually increase your risk of getting a UTI. “The female urethra is quite short in length. That makes it easier for bacteria to enter the urethra and travel into the bladder, making urinary tract infections more common after sex,” says Dr. Montville.
The best way to increase your chances of getting pregnant after sex is to know when you’re ovulating by tracking your menstrual cycle.
“Ovulation usually takes place between days 10 and 17 of the cycle (day 1 is the first day of a menstruator’s cycle),” explains Dr. Montville. “Using ovulation predictor kits can help you identify your most fertile window.” The ideal time to have sex to get pregnant is two days past the time of ovulation, says Dr. Bagdasarian.
While you’re trying to conceive, understanding your reproductive health (and talking to your health care provider about any pre-conception testing that might be relevant for you), taking prenatal vitamins containing folic acid, using sperm-friendly lubricant like Pre-Seed, switching to a pregnancy-safe skin care routine, and reading up on foods to avoid when trying to get pregnant can help make sure you’re physically prepared.
How soon after unprotected sex can I test for pregnancy?
After getting busy, you’ll probably start wondering how quickly you can take a pregnancy test (and perhaps asking yourself, “How many pregnancy tests should I take?”). Although it can be tempting to take a pregnancy test as soon as possible, the experts say it pays to wait at least 14 days after having unprotected sex.
“Checking too early can result in you having a false negative when, in fact, you may be pregnant, and this can result in undue anxiety and disappointment,” says Dr. Ahmad. “Trust me, I know. I have been pregnant five times, and I don’t always follow my own advice. But it’s best to wait.”
How long does it take to get pregnant?
One of the best predictors of fertility is age. The likelihood of a natural pregnancy within one year of trying is 86% for ages 20 to 24, 78% for 25 to 29, 63% for 30 to 34, and 52% for 35 to 39. If you’re under 35 year of age and have been trying for a year, or if you’re 35 or older and have been trying for six months, Dr. Ahmad recommends seeing a fertility specialist to get to the bottom of what might be causing infertility.
