What is ovulation?

Ovulation is a phase in the menstrual cycle when your ovary releases an egg (ovum). Once an egg leaves your ovary, it travels down your fallopian tube where it waits to be fertilized by sperm. On average, it happens on day 14 of a 28-day menstrual cycle.

Ovulation and your menstrual cycle

The process of ovulation begins when your hypothalamus (a part of your brain) releases gonadotropin-releasing hormone (GnRH). GnRH causes your pituitary gland (a gland in your brain) to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

Between days six and 14 of your menstrual cycle, FSH causes follicles (small sacs of fluid in your ovaries that contain a developing egg) in one ovary to begin to mature. During days 10 to 14 of the cycle, only one of the developing follicles forms a fully mature egg. Around day 14 in the menstrual cycle, a sudden surge in LH causes the ovary to release this egg. This is ovulation. After ovulation, the hormone progesterone rises which helps prepare your uterus for pregnancy.

Ovulation, conception and pregnancy

Once ovulation occurs, your egg travels through your fallopian tube. It’s in your fallopian tube that your egg meets sperm for fertilization. If conception occurs (sperm fertilizes your egg), the fertilized egg travels down to your uterus. After about a week, the fertilized egg (now a blastocyst) attaches to the lining of your uterus. This is called implantation. Release of the hormones estrogen and progesterone causes the endometrium to thicken, which provides the nutrients the blastocyst needs to grow and eventually develop into a baby. As cells continue to divide — some developing into the fetus, others forming the placenta — hormones signal your body that a baby is growing inside your uterus. This also signals your uterus to keep its lining, which prevents you from getting your period. Not getting a period is usually the first sign you’re pregnant.

When does ovulation occur?

In an average 28-day menstrual cycle, ovulation occurs about 14 days before the beginning of your next menstrual period. The exact timing varies — your cycle length may be longer or shorter. You may find it helpful to track your menstrual cycle using an app on your phone or a calendar. This can help you determine when ovulation is most likely to occur. Most people will have a period 14 to 16 days after ovulation, regardless of the length of their overall cycle.

How many hours does ovulation last?

An egg only survives 12 to 24 hours after ovulation. If sperm doesn’t’ fertilize the egg, your body reabsorbs it. Unlike your egg, sperm can survive for several days in your body.

How do I know I’m ovulating?

Pinpointing ovulation can be tricky. There are several methods people use to track their menstrual cycle and estimate when ovulation occurs. Since each method has its drawbacks, it’s always best to use more than one for the most accurate answer.

Menstrual cycle

Ovulation happens at around the midpoint of your cycle if you have a 28-day cycle (day 14). However, a “normal” cycle is anything between 21 and 35 days, so this means ovulation is unique to your menstrual cycle. Keep track of your cycle on paper or on an app on your phone for several months. Take note of any unusual symptoms. Most people ovulate 14 days before their period begins, regardless of cycle length.

Calendar method

People using the calendar method to predict ovulation, analyze six months of menstrual cycles to determine when they’re fertile. To calculate when you may be ovulating, you find your shortest cycle and your longest cycle in a six month period. You subtract 18 days from your shortest cycle and 11 days from your longest cycle. These two numbers give you the days in your cycle you’re most fertile. For example, if your cycle lengths are 31 and 18, your fertile time is day 10 to 20 of your cycle.

Cervical mucus

Cervical mucus is a vaginal fluid produced by your cervix. Your cervical mucus goes through stages during your menstrual cycle. Your cervical mucus is thick, white and dry before ovulation. Just before ovulation, your cervical mucus turns clear and slippery (like egg whites). This consistency makes it easy for sperm to swim up to meet your egg.

Basal body temperature

Your body temperature increases slightly during ovulation (typically about 0.5 to 1 degree). Take your temperature every morning using a digital thermometer meant specifically for measuring basal body temperature. This method only works if you take your temperature before you get out of bed and before you eat/drink. Record your results for several months and note what day of your cycle a temperature increase occurs.

Ovulation kits

Ovulation kits work similarly to at-home pregnancy tests because you pee on an indicator strip in the comfort of your own home. They work by detecting LH (luteinizing hormone) in your pee. LH is the hormone that surges before ovulation. A positive result means you’re about to ovulate (usually within 36 hours).

What are the symptoms of ovulation?

Every person is different and not everyone has signs of ovulation. In those that do, the most common symptoms are:

  • Tender breasts.
  • Bloating.
  • Minor pelvic or abdominal pain.
  • Light bleeding or spotting.
  • Changes in the position and firmness of your cervix.
  • Increased sex drive.
  • Heightened sense of smell, taste or sight.
  • Mood changes.
  • Appetite changes.

How many days during ovulation can you get pregnant?

Even though your egg only lives for 24 hours, sperm can live in your uterus for between three and five days. This means you can get pregnant from having sex from about five days before ovulation to one day after ovulation. If pregnancy is your goal, it’s better to have sperm already in your body when you ovulate. The highest probability of conception occurs when intercourse takes place one to two days before ovulation and on the day of ovulation.

Is pain during ovulation normal?

Yes, many people experience ovulation pain. Ovulation pain (or mittelschmerz) is cramping or pelvic pain that happens around ovulation. You typically feel the pain in your lower abdomen and pelvis, in the middle or on one side. Ovulation pain may happen when an egg bursts from a follicle (the sacs in your ovaries that contain eggs). It can even cause light bleeding.

Pain during the time of ovulation may also be caused by a medical condition, so it’s best to contact your healthcare provider to be sure the pain isn’t something more serious.

What happens if I’m not ovulating?

Certain health conditions or life events may affect ovulation or cause you to stop ovulating. Some of these are:

If your period is irregular or you go months without a period, you may have not be ovulating. Contact your healthcare provider if this is the case so they can rule out any serious conditions.

Do you still ovulate if you’re on birth control?

No, if you’re taking birth control pills or other hormonal contraception as directed, you shouldn’t ovulate. Keep in mind, this is only the case if you’re using pills, patches, IUDs or other devices exactly as prescribed. The hormones in birth control work by stopping ovulation and thickening cervical mucus (which makes it harder for sperm to swim).

Can you ovulate but not get your period?

Yes. You can ovulate but not get your “period.” Technically, if you’re ovulating regularly, you should also get your period regularly. However, it’s possible to get your period without actually ovulating and to ovulate but not have a true period.

Can medicine help you ovulate?

Yes, there are fertility medications to induce ovulation. Talk to your healthcare provider about your symptoms and goals, such as if you wish to become pregnant. They can work with you on the best treatment based on your condition.

A note from Cleveland Clinic

Ovulation is a process that occurs during your menstrual cycle. The exact timing of ovulation varies from person to person and even from cycle to cycle. Without ovulation, it’s hard for you to get pregnant or have regular menstrual periods. There are many methods available to help you predict ovulation. Knowing when you ovulate can help you either achieve a pregnancy or avoid a pregnancy. There are several health conditions that affect ovulation. Contact your healthcare provider if you’re concerned that you’re not ovulating.

Last reviewed by a Cleveland Clinic medical professional on 07/08/2022.

References

  • ACOG. Fertility Awareness-Based Methods of Family Planning. (https://www.acog.org/womens-health/faqs/fertility-awareness-based-methods-of-family-planning) Accessed 6/21/2022.
  • American Pregnancy Association. What is Ovulation? (https://americanpregnancy.org/getting-pregnant/infertility/understanding-ovulation/) Accessed 6/21/2022.
  • American Society of Reproductive Medicine. Ovulation Detection (https://www.reproductivefacts.org/news-and-publications/patient-fact-sheets-and-booklets/documents/fact-sheets-and-info-booklets/ovulation-detection/) & Optimizing Natural Fertility. (https://www.reproductivefacts.org/news-and-publications/patient-fact-sheets-and-booklets/documents/fact-sheets-and-info-booklets/optimizing-natural-fertility/) Accessed 6/21/2022.
  • Holesh JE, Bass AN, Lord M. Physiology, Ovulation. (https://pubmed.ncbi.nlm.nih.gov/28723025/) 2022 May 8. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan–. PMID: 28723025. Accessed 6/21/2022.
  • National Health Service. How can I tell when I'm ovulating? (https://www.nhs.uk/common-health-questions/womens-health/how-can-i-tell-when-i-am-ovulating/) Accessed 6/21/2022.
  • Office on Women’s Health: U.S. Dept of Health. Trying to conceive (https://www.womenshealth.gov/pregnancy/you-get-pregnant/trying-conceive) & Your menstrual cycle. (https://www.womenshealth.gov/menstrual-cycle/your-menstrual-cycle) Accessed 6/21/2022.

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