The general principle of how to get pregnant is simple, but in reality, it can be a lot more complicated than simply having unprotected sex. If you’ve been trying to get pregnant for a while, you may be wondering what’s taking so long. With no other issues identified (such as not having viable sperm), getting pregnant is like many things in life: all about timing.
Your fertile window is defined as the 6 days during your cycle that you can get pregnant, but it varies depending on a few factors (details below). If you do not have unprotected sex during your fertile window, your chances of getting pregnant during that cycle are nil, and you’ll have to wait until your next fertile window (1). If you need help with predicting when you ovulate and how to find your fertile window, you’ve come to the right place! Your fertile window is determined by the day you ovulate, so we will explain what you need to know about ovulation prediction to maximize your chances of getting pregnant.
Ovulation is when a mature egg is released from the ovary, which happens about once per month without any health conditions or medical interventions. You’re born with millions of eggs, but only about 400 eggs actually mature to ovulation (2). After your period ends, follicle stimulating hormone (FSH) causes about 15 to 20 eggs to begin maturing in each ovary, which are enclosed in their own fluid-filled sac called a follicle (3). The most variation in any given cycle will usually be in this phase because the maturation process can last anywhere from 8 to 21 days; on average, eggs take about 2 weeks to mature (3). During ovulation, the mature egg is released from the ovary and is swept through the fallopian tube. If sperm has made its way up the fallopian tube, the egg will be fertilized and travel down to the uterus, where it will implant. The egg only lives for about 24 hours (4), so if no sperm are around to fertilize the egg, the lining of your uterus is shed during your period, and the cycle begins again (5).
To learn more about the menstrual cycle and ovulation process, check out the Phases of the Menstrual Cycle.
The fertile window is typically a maximum of 6 days, including the day of ovulation, but the actual length of your individual fertile window depends on a variety of factors, including the lifespan of the sperm, your cervical mucus, and possibly your vaginal microbiome. Sperm can survive for 3-5 days inside the female reproductive tract (6), and your egg lives for about 24 hours. Some studies suggest that a healthy vaginal microbiome may also play a role in a healthy pregnancy and miscarriage; read more in Can a healthy microbiome prevent miscarriage?
Timing is important even within the fertile window; for the best chances of getting pregnant, unprotected sex needs to happen at least 2 days before ovulation (7). This way, the sperm is in the fallopian tube to meet the egg when it’s released (8).
Predicting ovulation and identifying the fertile window has historically not been an easy task, but now we have tools and research available to help us pinpoint this important event.
If you have questions or concerns about your cycle or are unsure if you are ovulating, contact your healthcare provider.
Although many apps and websites offer fertility predictions to help you conceive, these tend not to be accurate (12), so if you rely solely on them to calculate your fertile window, you may miss it entirely.
If you’re looking for an easier way to predict your fertile window before ovulation, check out our new product, the Priya Personal Fertility System. The Priya Sensor is an innovative temperature sensor that measures continuous core body temperature and pairs with the Priya App that uses an algorithm designed to identify the subtle temperature patterns that occur before ovulation.
Weschler, Toni. (2015). Taking Charge of Your Fertility: The definitive Guide to Natural Birth Control, Pregnancy Achievement, and Reproductive Health. P46-48
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