When taken regularly, birth control pills cause hormonal changes in a woman’s body. In most cases, those changes prevent ovulation from taking place.
While women can get pregnant at any point during their menstrual cycle, the risks of pregnancy are especially high before and during ovulation. The prevention of ovulation is one of the main ways that birth control pills prevent fertilization from occurring.
Ovulation and Birth Control Pills
So the pill prevents ovulation — great, but what exactly does that mean? Let’s break it down:
What Is Ovulation?
Ovulation refers to the release of a mature egg from the female ovary.
For most women, ovulation is a regular occurrence in the menstrual cycle. In the average cycle, ovulation typically begins sometime in the second week after the last menstrual period.
During ovulation, the egg moves from the ovary to the fallopian tube. Once released, it is viable for anywhere from 12-24 hours.
Because sperm can remain active for up to five days in the female reproductive system, the six days up to and including ovulation are known as the “fertile window.” The egg’s new location in the fallopian tube makes it much easier for sperm to reach it, greatly increasing the chances of pregnancy.
If fertilization does not occur in the 24 hours after ovulation, the egg will dissolve and the ovulatory period will be over. Over the next two weeks, hormone levels will decrease and the menstrual cycle will begin again.
How Do You Know if You Are Ovulating?
The best way to know whether you’re ovulating is by tracking the calendar. During the typical 28-day menstrual cycle, ovulation begins on day 14.
With that said, different women have different cycles. Yours might differ from the 28-day average.
You may also notice physical symptoms. Changes to your mood, body temperature, or the consistency of your vaginal fluid can all indicate ovulation is occurring.
Can You Get Pregnant When You’re Not Ovulating?
While ovulation is necessary for pregnancy to occur, having sex while not ovulating can still result in pregnancy.
Even outside of the fertile window, sperm can still survive in the female reproductive system. Rarely, they may persist until the next fertile window.
How Do Birth Control Pills Stop Ovulation?
Birth control pills lower the chances of pregnancy by interfering with the menstrual cycle and preventing the release of an egg.
The pill, along with other hormonal birth control methods like the patch and the shot, use some combination of estrogen and progestin to keep the egg from leaving the ovary.
Estrogen and progestin are hormones that women’s bodies produce automatically. Birth control pills slightly alter the levels of these hormones in a way that convinces the ovary not to release the egg during each cycle. If the egg is not released, conception cannot take place.
In order for the pill to work, it needs to be taken exactly as prescribed. The body is constantly attempting to return back to its natural hormonal levels, so birth control pills must be taken every day in order to keep the balance of hormones where it needs to be. If you’re taking the minipill — a progestin-only birth control — you need to be sure to take it within the same three-hour window each day in order to prevent egg release.
Is All of This Normal?
Altering levels of hormones in your body may sound scary, but there is nothing unusual or unsafe about how the birth control pill affects the body.
Preventing ovulation from taking place is unlikely to have any other serious effects on the body and is one of the most effective ways of preventing unwanted pregnancy. While some women may experience side effects while taking hormonal birth control, the pill is generally considered a safe and low-risk option for most women.
If you’re wondering whether birth control pills are the right option for you, reach out. Our team of medical experts here at Nurx is always available for questions.