Pain associated with ovulation usually starts just a few days before the egg is released from the ovary. The pain might increase at the time the egg ovulates, then fade quickly. Some women will continue to have mild symptoms up to their next period.
Duration of Pre-Ovulation Pain
In general, you can expect to ovulate about one to two days after your mid-cycle pain starts. A study published in 1980 in the British Medical Journal found 91 percent of the study women had one-sided pain 24 to 48 hours before ultrasound evidence of ovulation. For some women and for some cycles, pre-ovulation pain might start a few days earlier than that.
According to MedlinePlus, the pain around ovulation - known as mittelschmerz ("middle pain") - can include pre-ovulation, ovulation, and post-ovulation pain. Mittelschmerz occurs in only about 20 percent of women and:
- Often peaks at ovulation
- Decreases within minutes to a few hours, or a few days after ovulation
- Most often lasts 24 to 48 hours although a few women can continue to have a mild level of discomfort until the onset of their next period
- Can occur every cycle for some women or only occasional months for others
The gynecology book, Chronic Pelvic Pain in Women, notes:
- You will feel mid-cycle pain only on one side of your pelvic area during a menstrual cycle. The side depends on which ovary you randomly ovulate from during each cycle.
- Most women who experience mittelschmerz have only mild twinges or cramps, or mild stabbing pain, and only a few have severe pain that might require treatment.
If you are trying to identify the peak of your fertile window to get pregnant or to avoid pregnancy, mittelschmerz can be a useful fertility sign.
Factors That Can Affect the Onset of Pain
The timing of the onset of mid-cycle pain before ovulation vary from woman to woman and cycle to cycle. Your pre-ovulation pain might start earlier depending on factors such as:
- Your ovary was already enlarged at the beginning of the cycle - with ovarian cysts, for example
- How large your ovary gets during the events leading up to ovulation
- The presence of endometriosis on your ovaries or other pelvic organs
- There is scar tissue in your pelvic area from previous sexually transmitted infections of pelvic/abdominal surgery
These factors can also affect the intensity of your pain and how long the mittelschmerz symptoms last.
The Cause of Pre-Ovulation Pain
The pain that comes before you ovulate is likely caused by the growth of your ovarian follicles in which your eggs grow during the first half of your menstrual cycle. As your eggs mature and follicles fill with fluid, your gradually enlarging ovary can cause pressure or pain in your pelvic area.
The egg that is destined to ovulate grows faster than the others and can result in increased pain closer to ovulation. Abdominal bloating might also occur with the onset of pain and increase at the time of ovulation.
Pain at Ovulation
The rupture of the mature ovarian follicle to release the egg is thought to cause the pelvic pain felt at ovulation. As the egg bursts out of its follicle, the pain can increase and be intense for some women. This peak of your mittelschmerz pain lasts about 20 to 30 minutes according to the Chronic Pelvic Pain in Women reference cited above in the first section.
It is difficult to pinpoint the moment of ovulation based on your mid-cycle pain. However, if your mid-cycle pain suddenly increases and then fades soon after, this could be your clue that you just ovulated and are most fertile.
Pain From Fluid and Blood
Your pain can be more severe if you leak follicle fluid or blood from the ovulation site of your ovary into your pelvic cavity. These fluids can spread and cause pain throughout your pelvic area.
The more fluid that leaks and the greater the bleeding, the more the pain. Bleeding and pain can be severe enough that occasionally surgery is needed to drain the blood and repair the site of ovulation in the affected ovary.
Pain After Ovulation
The pain of ovulation usually lasts for one or two days, but you might continue to have some mild symptoms for two more weeks until your next period starts. Expect your symptoms to fade with each day as the activity in your ovary decreases, and any leaked fluid or blood re-absorbs from your pelvic cavity.
Note that crampy pain after ovulation might be contractions of your fallopian tube as your egg or early embryo travels towards your uterus.
Keep Track of Your Pain
If you get recurrent pain at mid-cycle, keep track of when it starts as a sign you are close to ovulation, the peak of your fertile days. Don't hesitate to call your doctor if your pain is moderate to severe, lasts more than two weeks, or is accompanied by other symptoms, such as vaginal bleeding or nausea and vomiting.