Ovulation 101: Learn more about cycles, calculators, and conception

Ovulation is part of a women’s menstrual cycle when the ovaries release an egg. Knowing what ovulation is, the timing of ovulation, and how to track it is a great way to stay in tune with one’s body. Knowing when they are ovulating can help women avoid getting pregnant or help them conceive. Let’s take a look at the basics of ovulation and FAQs about family planning.

Ovulation cycle: When does ovulation occur?

Ovulation occurs once a month for women. Here’s a timeline of the average menstrual cycle:

• Menstruation (days 1-7): The shedding of uterine lining
• Follicular phase (days 1-14): Follicles develop into mature eggs
• Ovulation (days 14-15): A mature egg is released and travels to the uterus to be fertilized
• Luteal phase (days 16-28): The egg is either fertilized and the body produces progesterone to support an early pregnancy, or the egg isn’t fertilized and the lining of the uterus breaks down

Menstruation and follicular phase

The average menstrual cycle runs on a 28-day cycle, with the first day of a period marking day one, and the first day of the next period marking day 28. The first half of a woman’s cycle is called the follicular phase. During this phase, estrogen levels rise, and the pituitary gland releases follicle-stimulating hormone (FSH), which allows a few follicles to develop into mature eggs. However, only one egg releases during ovulation.

Ovulation

Ovulation happens about two weeks after the first day of a menstrual cycle. So if a period marks day one of a menstrual cycle, this means the ovulation date would be around day 14, halfway through the menstrual cycle. 

During ovulation, an egg travels down a fallopian tube and into the uterus, where it can fertilize. A woman can only ovulate once in a single cycle, but it’s possible to release one egg from each ovary. If this happens and the woman gets pregnant, they’ll have non-identical twins. (Identical twins come from one fertilized egg splitting into identical copies of itself.)

This ovulatory period is the best time to get pregnant. Even though the time of ovulation is short, lasting about 12 to 24 hours, women can still get pregnant if they have sexual intercourse one to five days before ovulation. Sperm can survive in the female reproductive tract for several days. If she hasn’t had unprotected sex before ovulation or during it, a woman won’t be able to get pregnant until the next time she ovulates.

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Luteal phase

The luteal phase follows ovulation, lasts for about 14 days, and ends on the first day of a woman’s menstrual cycle. If the egg is fertilized, the body will continue to produce progesterone and the lining of the uterus will support early pregnancy. If the egg doesn’t fertilize, it’s released from the uterus on day 28 of the menstrual cycle with the start of a menstrual period as the uterine lining sheds. The average woman’s period lasts three to seven days. 

Ovulation calculators: How to track ovulation

Recent technology has made tracking ovulation so much easier. There are lots of options for women and couples who’re wanting to get pregnant or avoid getting pregnant by tracking ovulation.      

Here are some methods to track ovulation: 

• Traditional calendar
• Ovulation calculator
• Menstrual cycle tracking app
• Ovulation tests  
• Basal body temperature measurements
• Cervical mucus production tracking

“The best way to detect when ovulation will occur, especially for a woman trying to conceive, is to use ovulation predictor kits, which are urine tests that detect luteinizing hormone (LH)—the hormone that initiates ovulation,” says Eric Flisser, MD, a board-certified obstetrician-gynecologist at Reproductive Medicine Associates of New York. “Typically, when a positive test is detected, ovulation will occur in 24 to 48 hours.”  

Talk with your OB-GYN to learn more about how to track ovulation and different tracking methods.

Is ovulation the only time you can become pregnant?

The best day to conceive is the day of ovulation or the day after—usually days 14 and 15 of the average menstrual cycle. However, women can still get pregnant in their fertile window, which is the day of ovulation and five days before it (days 10-15). Sperm can live in the reproductive tract for multiple days. Women won’t be able to get pregnant after ovulation until the next cycle.  

How do you know if you are ovulating?

Ovulation pain is often the first indication for many women that they’re ovulating. Here are some symptoms of ovulation:      

• Lower-abdominal pain that only occurs on one side
• Spotting
• Tender breasts
• Increased sex drive
• Bloating
• Slightly increased basal body temperature  
• Lower back pain 
• A heightened sense of smell 

If none of these symptoms are present, women can still know if they’re ovulating by using an ovulation calendar, an ovulation predictor kit, or by tracking their menstrual cycle in other ways.    

Ovulation pain

Ovulation pain is sometimes called mittelschmerz, which comes from the German words “middle” and “pain” because of its occurrence in the middle of the menstrual cycle. Painful ovulation could be a sign that the body’s ready to get pregnant. However, having no ovulation pain doesn’t mean a woman’s infertile. Many women are asymptomatic when they ovulate.

Painful ovulation happens for many women, but experiencing pain doesn’t mean there’s anything wrong. Ovulation pain is normal and happens because of how the body functions. Before an egg is released from an ovary, it grows and can cause the ovary to enlarge, which can cause pain on one side of the abdomen. The released egg travels with follicular fluid and a little bit of blood, which can irritate the abdomen and cause pain.        

Here are some other symptoms women might have when they’re ovulating:  

• Dull or sharp lower-abdominal pain
• Breast tenderness 
• Spotting
• Bloating
• Lower back pain

Here are some remedies to alleviate ovulation pain:    

• Use a heating pad
• Take a warm bath
• Try over-the-counter pain medications like ibuprofen

Abdominal pain, spotting, or other symptoms that don’t go away after a few days might require some medical attention. A healthcare provider can look for underlying health conditions that could be causing these symptoms to persist or worsen.    

Irregular ovulation

Everyone will experience ovulation a little bit differently, but irregular ovulation could lead to fertility problems and an inability to get pregnant. Here are some underlying conditions that could affect women’s health:

• Damaged or blocked fallopian tubes
• Ovulation disorders like polycystic ovarian syndrome (PCOS) or hypothalamic dysfunction 
• Endometriosis
• Uterine abnormalities
• Cervical problems
• Excessive production of the hormone prolactin by the pituitary gland 

How to induce ovulation

An OB-GYN is the best person to ask for medical advice on what to do next when it comes to irregular ovulation or fertility problems. He or she can help determine any underlying causes and may recommend a treatment plan that involves one or more of the following: 

• In vitro fertilization (IVF)
• Fallopian tube surgery
• Hysteroscopic surgery 
• Intrauterine insemination 
• Lifestyle changes like exercising and eating healthy 
• Stimulating ovulation with fertility drugs

Here are some commonly prescribed fertility drugs that your OB-GYN may prescribe or recommend to induce ovulation: