When Does Ovulation Occur?

When Does Ovulation Occur

Understanding when ovulation occurs is crucial for individuals trying to conceive or practicing natural family planning. Ovulation is the release of an egg from the ovary, making it the most fertile time in a woman’s menstrual cycle. However, the timing of ovulation can vary from person to person and even from cycle to cycle. In this comprehensive guide, we will explore the factors that influence ovulation, methods to track and identify ovulation, and the best times to conceive.

The Menstrual Cycle and Ovulation

The menstrual cycle is the monthly hormonal cycle that prepares the uterus for pregnancy. On average, the menstrual cycle lasts about 28 days but can range from 21 to 35 days (Stanford, 2015). The first day of the cycle is the first day of menstruation, and the last day is the day before the next period starts (Stanford et al., 2002). Ovulation typically occurs about 14 days before the start of the next period.

Factors Affecting Ovulation

Several factors can influence when ovulation occurs, including:

  1. Hormonal Balance: Hormones like estrogen and luteinizing hormone (LH) are crucial in triggering ovulation. Any hormonal imbalances can disrupt the timing of ovulation.
  2. Stress: High-stress levels can affect the hormones responsible for ovulation, potentially delaying or preventing it.
  3. Age: As women age, their ovarian reserve decreases, leading to irregular and less frequent ovulation.
  4. Health Conditions: Certain health conditions, such as polycystic ovary syndrome (PCOS) or thyroid disorders, can affect ovulation.
  5. Weight: Extreme weight fluctuations, such as being underweight or overweight, can disrupt the hormonal balance and, consequently, ovulation.

Signs and Symptoms of Ovulation

Knowing the signs and symptoms of ovulation can help individuals identify their most fertile days. Some common signs include:

  1. Change in Cervical Mucus: Around the time of ovulation, cervical mucus becomes thinner, clearer, and more slippery, resembling raw egg whites (Ecochard et al., 2015).
  2. Basal Body Temperature (BBT): BBT is the body’s resting temperature. It tends to rise slightly after ovulation due to increased progesterone levels (Berglund Scherwitzl et al., 2015).
  3. Ovulation Pain: Some individuals experience mild pelvic pain or discomfort around the time of ovulation (Stanford, 2015).
  4. Ovulation Predictor Kits: These kits detect the surge in LH hormone that occurs 24 to 36 hours before ovulation (Stanford et al., 2002).

Tracking Ovulation

Tracking ovulation can help individuals determine their most fertile days and improve their chances of conception. Various methods can be used to track ovulation, including:

Menstrual Cycle Tracking

Keeping track of the menstrual cycle can provide valuable insights into ovulation patterns. By recording the first day of menstruation and the length of each cycle, individuals can estimate when they are most likely to ovulate.

For example, if someone has an average menstrual cycle of 28 days, ovulation is likely to occur around day 14. However, if their cycle is 35 days, ovulation is more likely to occur around day 21 (Stanford, 2015).

Cervical Mucus Observation

Monitoring changes in cervical mucus can be an effective way to identify the fertile window. As ovulation approaches, cervical mucus becomes clearer, more slippery, and stretchy, resembling raw egg whites. This type of mucus provides an optimal environment for sperm to swim and survive (Ecochard et al., 2015).

Basal Body Temperature (BBT) Charting

Tracking basal body temperature involves measuring the body’s resting temperature every morning before bed. After ovulation, progesterone causes a slight increase in body temperature. By charting the temperatures over several cycles, individuals can identify patterns and pinpoint when ovulation occurs (Berglund Scherwitzl et al., 2015).


Ovulation Predictor Kits (OPKs)

Ovulation predictor kits, available over the counter, detect the luteinizing hormone (LH) surge that occurs before ovulation. By following the instructions provided with the kit, individuals can test their urine for the presence of LH and determine their fertile days (Stanford et al., 2002).

The Fertile Window

The fertile window refers to the days in a woman’s menstrual cycle when pregnancy is most likely to occur. It includes the day of ovulation and the five days leading up to it. Having intercourse during this window maximizes the chances of conception (Stanford et al., 2002).

Pregnancy is Possible on the Days Leading up to Ovulation

While the egg is only viable for around 24 hours after ovulation, sperm can survive in the female reproductive system for up to five days. This means that pregnancy can occur if intercourse takes place in the days leading up to ovulation (Stanford et al., 2002).

Timing Intercourse for Conception

To optimize the chances of conception, it is recommended to have intercourse in the days leading up to and including the day of ovulation. This ensures sperm is present in the fallopian tubes when the egg is released (Stanford et al., 2002).

Myth Busting

There are several myths and misconceptions surrounding ovulation and fertility. Let’s debunk some of the most common ones:

Myth: A Woman Can Get Pregnant Any Time of the Month

Fact: Pregnancy can only occur during a few days of a woman’s menstrual cycle. Sperm can survive for up to five days, and the egg is viable for about 24 hours after ovulation. Therefore, conception can only happen if intercourse takes place in the days leading up to and including ovulation (Stanford et al., 2002).

Myth: Having Sex After Ovulation Increases the Chances of Pregnancy

Fact: Once ovulation has occurred, the egg moves down the fallopian tube and is no longer viable for fertilization. Therefore, having intercourse after ovulation does not increase the chances of pregnancy during that menstrual cycle (Stanford et al., 2002).

Myth: Having Sex Before Ovulation Can Lead to Pregnancy

Fact: While it is theoretically possible for sperm to survive in the female reproductive system for up to five days, the likelihood of pregnancy is significantly lower if intercourse occurs before ovulation. The highest chances of conception occur in the days leading up to and including ovulation (Stanford et al., 2002).


Understanding when ovulation occurs is essential for individuals trying to conceive or practicing natural family planning. Individuals can identify their most fertile days by tracking menstrual cycles, observing changes in cervical mucus, charting basal body temperature, or using ovulation predictor kits. Timing intercourse to coincide with the fertile window increases the chances of conception. Debunking common myths about ovulation and fertility can provide individuals with accurate information to make informed decisions about family planning.