What You Need to Know About Ovulation

Ovulation is one of several biological processes in which the body attempts to move toward conception. It occurs once per month in the reproductive system and refers to the phase of the menstrual cycle when the ovary releases a mature egg.

"The point of the ovary is to store and house the eggs," said Laura Purdy, M.D., an OB-GYN based in Tennessee and the chief medical officer of Wisp, a women's sexual and reproductive telehealth provider.

She explained that females are born with all of their eggs for a lifetime, compared with males, who continue to produce sperm throughout their entire lives.

While hundreds of thousands of immature eggs—the exact number is dependent on your age—live inside the ovaries, once an individual reaches puberty, one lucky winner is released each month to potentially be fertilized.

How it works

Ovulation comes directly after the follicular phase, which often overlaps with the last few days of menstruation. While it may sound simple, the process of ovulation is actually quite a delicate dance, according to Purdy, because it relies on hormone surges from both the ovaries and the brain to function properly.

"Ovulation is an interplay between the brain and the ovaries," she said.

During the follicular phase, a surge in estrogen occurs, according to Purdy. Sometime between the sixth and 14th day of the cycle, this estrogen spike triggers a surge in follicle-stimulating hormone (FSH), secreted by the brain, which signals for an egg to develop and mature inside the ovary.

A surge in luteinizing hormone (LH), which is also secreted by the brain, causes the ovary to release the egg, completing the process of ovulation.

An individual is most fertile a few days before, during and after ovulation.

After ovulation, the luteal phase begins. This is when the egg travels down the fallopian tube, where it waits to be fertilized by a sperm, Purdy explained. Also during this phase, a release of progesterone thickens the uterine lining, preparing for a fertilized egg to be implanted.

Whether or not the egg is fertilized during this period determines if implantation will occur and the person will become pregnant, or if the uterine lining and egg will shed in the process known as menstruation.

If fertilization doesn't occur and the egg can't implant itself in the uterine lining, progesterone and estrogen levels fall. This drop in hormone levels is what causes the uncomfortable symptoms associated with premenstrual syndrome (PMS), such as lethargy and irritability, according to Purdy.

"Some people say they feel like they got hit by a truck," she said. "And then menses happens."

Menstruation marks the end of the monthly cycle, and then it begins all over again.

On the other hand, if someone has sex directly before, during or after ovulation, conception can occur. Once the sperm are ejaculated into the posterior vaginal canal, they then must get through the cervical mucus, the cervix and the uterus to meet the egg in the fallopian tube.

"During ovulation, the entire reproductive system of the woman—if the conditions are right—is perfectly hospitable to the acceptance and transmission of the sperm," Purdy said.

Millions of sperm die along the way, but it takes only one sperm to meet the egg at the peak of the fallopian tube and make it through the protective coating that surrounds the genetic material inside the egg for fertilization to happen.

Once it does, the fertilized egg implants itself in the uterine lining, resulting in pregnancy rather than menstruation.

Signs you might be ovulating

While most people are familiar with the common symptoms associated with menstruation, many are unaware that ovulation can also result in physical symptoms.

In fact, most people have no clue when they're ovulating. But knowing where you are in your cycle—and, specifically, when you're ovulating—can help you take better care of yourself and also help you time sexual intercourse if you're looking to conceive.

While there are tests you can take that tell you for sure, there are also physical signs and symptoms you can look out for, according to Purdy.

Due to hormonal changes that occur during ovulation, you might experience nausea, headaches, soreness in the pelvis or lower abdomen, and breast tenderness. You might also see some light spotting or brown discharge, and your cervical mucus can become sticky, stretchy and wet.

Some people experience a heightened sensitivity to aromas and flavors, and you might also notice an increase in your libido.

Signs you might not be ovulating

A number of factors can prevent someone's natural cycle from progressing, inhibiting ovulation. Hormonal birth control and Plan B, for example, mimic pregnancy and suppress ovulation to prevent conception.

Likewise, the body usually knows not to ovulate if you are pregnant or breastfeeding.

Health issues can also prevent ovulation because the process is such a delicate dance. Everything from stress to poor diet to excessive exercise can cause a hormone imbalance and stop ovulation from happening. Conditions including polycystic ovary syndrome (PCOS), hypothyroidism and endometriosis might also inhibit ovulation.

If you're having trouble conceiving or you're experiencing irregular or skipped periods, or if you believe you might not be ovulating for some reason, talk to your healthcare provider about your concerns to get some answers and figure out how to proceed.