LIVE

Did you know there's a six-day span each month when you're most likely to get pregnant? Here's how to calculate your fertile window.

By Nicole Harris
January 17, 2019
Advertisement
couple surprised about fertility facts
Credit: George Rudy/Shutterstock 

As any trying to conceive (TTC) couple knows, a woman is most likely to get pregnant during her “fertile window,” which includes the day of ovulation and the five days leading up to it. Here’s your ultimate guide to finding your fertile window and increasing your odds of successful conception.

What is a Fertile Window?

During ovulation, an egg released from a woman’s ovary travels down her fallopian tube. It survives in the reproductive tract for 12-24 hours. Conception can occur if sperm fertilizes the egg during this time; otherwise, the egg sheds with the uterine lining during menstruation.

Your chances of getting pregnant are highest within 24 hours of ovulation and one day beforehand. But conception is also possible if you have sex in the five days leading up to ovulation, says Rashmi Kudesia, M.D., an Ob-Gyn and reproductive endocrinology and infertility specialist at Houston Methodist and Houston IVF. That’s because sperm can survive in the reproductive tract for five days, meaning that days-old sperm can still fertilize a newly released egg. 

How to Calculate Your Fertile Window

If you’re looking to calculate your fertile window, online ovulation calculators (like this one from Parents) can give speedy results. But since few women have consistently regular cycles, they aren’t always accurate. Here are some of the most effective ways to calculate your fertile window.

Tracking Your Cycle

“When trying to predict the fertile window and ovulation, it’s important to determine cycle length by creating a menstrual diary,” says Sharifa Menon, M.D., F.A.C.O.G, an Ob-Gyn at Westchester Medical Center, the flagship of the Westchester Medical Center Health Network (WMCHealth). Start by tracking your menstruation for a few months using a paper journal or mobile app (check out our top picks here). Then look at the data to determine your average cycle length.

The first day of the menstrual period is considered day one of the cycle, and ovulation usually happens about 14 days before your next period is due. “For example, if the interval between periods is 28 days, we would predict ovulation occurs on day 14. Alternatively, if the cycle length is 30 days, we would expect ovulation on day 16 of the cycle,” says Dr. Menon. Since a woman is most likely to conceive on the day of ovulation and the five days before it, the fertile window for these examples is days 9-14 and days 11-16, respectively.              

Ovulation Predictor Kits (OPKs)

Available at most drug stores, ovulation predictor kits (OPKs) use a urine test to identify the fertile window. They work by monitoring the luteinizing hormone (LH), which surges roughly 36 hours before ovulation. TTC couples should plan to have intercourse shortly after detecting the surge.

Monitoring Cervical Mucus

“During the fertile window, cervical mucus increases in volume, and it tends to be more clear and slippery compared to other times of the cycle,” says Dr. Menon. If you notice your mucus looking slimy and thick (almost like egg whites) there’s a good chance you’re ovulating.

Charting Basal Body Temperature (BBT)

A woman’s resting body temperature rises during ovulation by at least two-tenths of a degree. Taking your basal body temperature first thing in the morning with a BBT thermometer can help monitor ovulation. "As this method only detects ovulation after it has already occurred, I would only recommend this to help confirm ovulation or gain a sense of one’s average ovulation day,” says Dr. Kudesia.

Fertility Monitors

These ovulation calculators monitor your LH and estrogen to determine your most fertile days. They’re effective but pricier than ovulation predictor kits.

Visiting a Doctor

For those with fertility issues, doctors can sample blood to see progesterone levels, which can confirm ovulation. "Doctors also can use a pelvic ultrasound to monitor ovulation," says Jingwen Hou, M.D., Ph.D., an Ob-Gyn specializing in reproductive endocrinology and infertility at Kaiser Permanente in Hawaii.

When Will I Conceive?

Of course, the best way to conceive is through regular intercourse. Aim to have sex every 1-2 days during the fertile window. Keep in mind, however, that conception probably won’t happen right away. “Even if the timing is perfect and there are no other diagnoses at play, the chance of pregnancy per month is about 25 percent for young women (under the age of 30) and drops to less than 5 percent by the time we get to our 40s,” says Dr. Kudesia.

She also warns that if your typical menstrual cycle isn't between 21-35 days, you might not ovulate regularly. Couples may be suffering from infertility if they’ve haven’t conceived after one year of trying (or 6 months of trying if they’re over 35). In this case, consider visiting a reproductive endocrinology and infertility specialist. “There are many factors that could be at play – some relate to lifestyle and may be modifiable, but in other cases, medication is required to induce ovulation,” she says.

Comments (3)

Anonymous
December 20, 2020
my partner and I have been trying for a baby for over two years now, We were going to a fertility clinic for about 5 months before somebody at baby center told us to contact this spell caster who is so powerful, We contacted him at this email; babaka.wolf@gmail.com or Facebook at priest.babaka , for him to help us, then we told him our problem, he told us that we will conceive once we follow his instructions ,but after two years of trying we were at a point where we were willing to try anything. And I'm glad we came to Priest Babaka, Because his pregnancy spell cast and herbal remedy help us, and I honestly believe him, and his gods really helped us as well, I am thankful for all he has done. contact him via email: babaka.wolf@gmail.com or Facebook at priest.babaka if you are trying to have a baby or want your lover back. he has powers to do it, he has done mine
Anonymous
November 16, 2020
Hey pals, this year is a precious year to me. I am Bimmer Anna from Dallas Texas, 1004 Birdview road. I have being married for 6 years without a crying baby in my matrimonial home which made my husband separated me. Early this year i saw a testimony about Dr Ogume on how he has helped women get pregnant and bring back lost love with his herbs, so I contacted him and now I'm happy to say Dr ogume made me pregnant and bring back my husband. This call for a big celebration, You can contact Dr Ogume with his contact details I used in contacting him. Contact email: ogumespiritualtemple@gmail.com Contact WhatsApp: +2348107381533
Anonymous
April 12, 2020
THIS IS H0W MAMA A SPIRITUAL HEALER BROUGHT BACK MY LOVER BACK CONTACT HER ON +27673651672 by: MICHEAL Thanks to Dr MAMA for bringing back my lover, my lover left me because of his secretary in the office and he proposed marriage to her when i contacted Dr mama on whatsapp she stopped the marriage and made my man come back to his sense and realised that the woman was using charm on him after Dr mama cast a spell that is when my man came back to me and apologised that is how me and my man became husband and wife after Dr mama cast spell on him and destroyed the charm the woman was using on my man. Dr mama removed the charm and restored our relationship back.contact her for any kind of help via her whatsapp number +27673651672