When you’re ovulating, one of your ovaries releases a mature egg into your fallopian tube, where it can be fertilized by sperm for roughly 12 to 24 hours. This happens about 12 to 14 days before your next period starts. Beyond that core event, your body goes through a cascade of hormonal shifts that produce real, noticeable changes you can feel and track.
The Hormonal Chain Reaction
Ovulation doesn’t happen spontaneously. It’s triggered by a precise sequence of hormonal signals. Your hypothalamus (a small control center in your brain) releases a hormone that tells your pituitary gland to produce two key players: luteinizing hormone (LH) and follicle-stimulating hormone (FSH). FSH does what its name suggests, stimulating a group of follicles in your ovary to grow during the first half of your cycle. Each follicle contains an immature egg.
As those follicles develop, they produce rising levels of estrogen. Eventually, one dominant follicle pulls ahead. When estrogen hits a critical threshold, it triggers a sudden spike in LH, often called the “LH surge.” This surge is the direct signal that causes the dominant follicle to rupture and release its egg. The whole surge-to-release process takes about 24 to 36 hours, which is why ovulation predictor kits test for LH in your urine. They’re approximately 99% accurate at detecting that surge.
When Ovulation Happens in Your Cycle
The common shorthand is “day 14,” but that only applies to a textbook 28-day cycle. The more reliable rule is that ovulation occurs about 12 to 14 days before the start of your next period. So if your cycle runs 32 days, you likely ovulate around day 18. If it’s 26 days, closer to day 12.
This matters because the first half of your cycle (before ovulation) is the part that varies most in length. The second half, after ovulation, is relatively fixed at around two weeks. If your cycles vary by more than seven days month to month, or fall outside the 21-to-35-day range, that inconsistency may reflect a hormonal imbalance that makes ovulation timing harder to predict.
Physical Signs You Can Feel
Some women feel ovulation happen. A one-sided lower abdominal pain called mittelschmerz (German for “middle pain”) can occur right around the time the egg is released. It ranges from a mild twinge to a sharper cramp and typically lasts a few minutes to a few hours, though it can occasionally stretch to a day or two. Some women get it every month, others only occasionally, and many never notice it at all. The side can switch from month to month depending on which ovary releases the egg.
Other physical signs during your fertile window include mild bloating, breast tenderness, and a heightened sense of smell. Some women notice light spotting, which can happen when the follicle ruptures. A slight increase in sex drive is also common, driven by the same hormonal shifts that trigger the egg’s release.
Cervical Mucus Changes
One of the most reliable signs of approaching ovulation is a change in cervical mucus. In the days leading up to egg release, rising estrogen levels cause your cervix to produce mucus that’s slippery, stretchy, and wet, closely resembling raw egg whites. You’ll typically notice this texture for about three to four days. On a 28-day cycle, that window usually falls around days 10 through 14.
This consistency isn’t random. Thin, wet mucus creates a hospitable pathway for sperm to swim through the cervix and up into the uterus. After ovulation, progesterone takes over and the mucus becomes thicker, stickier, and less transparent, essentially forming a barrier. Tracking this shift from sticky to egg-white to sticky again is one of the oldest and most accessible ways to identify your fertile window without any tests or devices.
Your Cervix Shifts Position
Your cervix itself physically changes during ovulation. Earlier in your cycle, it sits lower in the vaginal canal and feels firm, similar to the tip of your nose. As ovulation approaches, it rises higher, softens to a texture more like your lips, and opens slightly. That slight opening allows sperm easier entry. After ovulation passes, it drops back down, firms up, and closes again. These changes are subtle, but women who check cervical position regularly can learn to distinguish them over a few cycles.
Your Temperature Rises After Ovulation
After the egg is released, progesterone production ramps up. One side effect: your resting body temperature increases slightly, typically less than half a degree Fahrenheit (about 0.3°C). This is called a basal body temperature shift, and it only shows up if you measure your temperature first thing in the morning before getting out of bed, using a thermometer sensitive enough to detect small changes.
The catch is that the temperature rise happens after ovulation, not before. So it confirms that ovulation already occurred rather than predicting it in advance. Over several months of tracking, though, the pattern can help you anticipate when ovulation is likely to fall in future cycles.
The Fertile Window Around Ovulation
Once released, an egg survives for less than 24 hours. Sperm, however, can live inside the reproductive tract for up to five days under the right conditions (particularly when that egg-white cervical mucus is present). This means your fertile window is roughly six days long: the five days before ovulation plus the day of ovulation itself. The highest chance of conception comes from the two days leading up to and including the day the egg is released.
If you’re trying to conceive, this is why timing matters more than frequency. If you’re trying to avoid pregnancy, it’s why methods based on cycle tracking require careful, consistent monitoring of multiple signs, not just calendar counting. Irregular cycles make this especially tricky, since the day of ovulation can shift significantly from one month to the next.
What Happens If the Egg Isn’t Fertilized
If sperm doesn’t reach the egg within that narrow window, the egg breaks down and is reabsorbed by the body. The empty follicle left behind on the ovary transforms into a temporary structure called the corpus luteum, which produces progesterone to maintain the uterine lining for about two weeks. When no pregnancy occurs, progesterone drops, the lining sheds, and your period begins, restarting the cycle.