If you’re trying to get pregnant (or avoid pregnancy), you need to know your fertile window. Here’s how.
The fertile window refers to the small period of time in your menstrual cycle in which you are most likely to get pregnant.
If you're trying to conceive, knowing your fertile window increases your chances of pregnancy during intercourse. And if you're avoiding pregnancy, having sex outside the fertile window significantly reduces your chances of getting pregnant.
So, how can you figure out what your fertile window is? Here’s your full-proof guide.
Fertile window meaning Your fertile window is the time in your cycle when you’re likely to get pregnant. This period typically includes the five days before ovulation and 24 hours after you ovulate.
>>MORE: When Am I the Most Fertile?
Essentially, if you want to find your fertile window, it’s crucial to track your ovulation .
Ovulation is one part of your menstrual cycle. Your menstrual cycle begins on the first day of your period and lasts until the first day of your next period. An average menstrual cycle lasts 28 days but can range from 21 to 35 days.
During your menstrual cycle, your hormones fluctuate. Your uterine lining gets thicker, and your hormones stimulate the growth of follicles in your ovaries to develop a mature egg. Ovulation occurs when one of your ovaries releases the mature egg, usually around day 14 of your cycle.
The egg then travels through one of your fallopian tubes to your uterus, where it is ready to be fertilized by sperm. If the egg is fertilized by sperm it attaches to your uterine wall, and you become pregnant. If not, hormone levels drop and your uterine lining sheds, resulting in menstruation.
Even though your egg isn’t fully mature before ovulation, sperm can live in your fallopian tube for up to five days and can fertilize the egg as soon as it’s released. This means that the fertile window is about six days total—starting about five days leading up to ovulation and lasting until the day after.
Fertile window vs. ovulation The fertile window isn’t the same as ovulation, but ovulation is a crucial part of the fertile window. Both are crucial time periods if you’re trying to conceive (or avoid conception).
Ovulation is when your ovaries release a mature egg, which sperm can then fertilize. In order to become pregnant, you need a fertilized egg.
The fertile window isn’t just the day of ovulation, but the five days before and the day after. Why? Sperm can live in the fallopian tube for up to five days—which means if you want to conceive, you’ll need to have sex either in the days leading up to ovulation, or while you’re ovulating.
How to find your fertile window Knowing if and when you ovulate is integral to understanding your fertile window.
Yet figuring out when you ovulate isn’t always as easy as counting 14 days from your period. Menstrual cycles vary for each person. Ovulation can also change in each cycle, and for those with irregular periods , tracking your fertile window can be even harder and unreliable.
Tracking your period Tracking your menstrual cycles in a calendar or period tracking app can help you figure out when you’re ovulating—and therefore find your fertile window—if you have a consistent cycle.
Tracking physical signs of ovulation Your body gives off physical signs that you’re ovulating, too. Look out for bodily changes like vaginal mucus, which becomes heavy and slippery during ovulation. You can also record your basal body temperature , or your temperature when your body is at rest—which dips slightly, then increases 0.5°F after ovulation.
>>MORE: Top 5 Signs of Ovulation: What To Look Out for if You’re Trying To Conceive
Using traditional ovulation predictor kits Before you ovulate, the amount of luteinizing hormone in your body rapidly increases, which is often referred to as the LH surge . Traditional ovulation predictor kits measure the levels of LH in your body and will say that you’re ovulating if the amount of LH is above a certain threshold.
While this can be a helpful indicator of ovulation, it’s important to note that traditional ovulation predictor kits aren’t accurate for everyone. The “threshold” is simply an average level for an LH surge. For example, if you have low LH levels, the ovulation predictor kit might not pick up on an LH surge even if you’re experiencing one because your levels of LH don’t increase up to the test’s standard. This means you’d get a negative result from the kit—even though you did ovulate.
Tracking your hormones Tracking your specific hormone levels can be one of the most accurate ways to not only figure out when you’re ovulating, but confirm you have definitely ovulated.
Digital ovulation predictor kits like Oova can accurately monitor your specific hormone levels to identify your fertile window. Oova measures three hormones—luteinizing hormone, E3G (an estrogen metabolite), and PdG (a progesterone metabolite) —to measure the exact length of your specific cycle and confirm that you’ve ovulated.
Fertile window: the bottom line The fertile window is the period of time in your cycle when it’s more likely that you’ll get pregnant. It typically makes up the five days before ovulation and the day following—which means to find your fertile window, you need to track your ovulation.
It’s important to record and gather your own data to understand your ovulation patterns, although stress, lifestyle changes, and ovarian conditions can interfere with some of these body measurements and at-home tests. And while ovulation is crucial to conception, other factors like the viability of sperm and egg can also interfere with fertility and chances of getting pregnant.
Utilizing different methods to monitor ovulation, from recognizing signs of ovulation to tracking your hormones, can be helpful in empowering you to understand and take control of your reproductive health.
