Women and couples that are trying to conceive have likely already encountered the terms “high fertility” and “peak fertility” — but what do they mean, and why do they matter? In this blog, we discuss the difference between high fertility vs peak fertility, and how they relate to the likelihood of conceiving. But before we dive into it, note that many women experience irregular cycles, which can result in varying lengths of high fertility and peak fertility windows, as well as their ovulation schedule. Those with regular cycles may experience these phases like clockwork each month, but those with irregular cycles may experience them at varying times from month to month.

Key Fertility Terms to Remember

Before getting into the details, let’s cover our bases with some important terminology that will pop up later:

• Menstrual cycle — This cycle, which averages between 24 and 38 days, begins when a female gets their period, or menses. It involves the shedding of the uterine lining to prepare the body for a potential pregnancy.
• Ovulation — This is the process when the ovaries release an egg into the fallopian tube and uterus. It is triggered by a surge in the luteinizing hormone.
• Egg viability — Once the egg is in the uterus, it must be fertilized by a sperm within 24 hours in order to become pregnant.

What is High Fertility?

High fertility refers to the timeframe in a female’s menstrual cycle during which the ovaries generate more estrogen as a fertile egg grows. For many biological women, this period typically happens in the five-day window before ovulation, as sperm is able to live in a female’s body for that long. That’s why this period of high fertility is often called the “fertility window” — because it’s a range of days, depending on the sperm and egg.

What is Peak Fertility?

Peak fertility has a shorter, and more specific, timeframe compared to high fertility as it typically occurs toward the end of the five-day fertility window. It starts approximately the day before ovulation, until the day of ovulation. Ovulation occurs about 24 to 36 hours after the luteinizing hormone surges, and then the developed egg is released into the fallopian tube. It is only viable for 24 hours in the peak fertility window. As the word “peak” suggests, these two days in a woman’s cycle are when they have the highest chance of conceiving if they engaged in unprotected sex or insemination.

High Fertility vs Peak Fertility: What’s More Important for Conception?

The chances of conceiving following unprotected sexual intercourse or insemination through other means are highest during periods of high and peak fertility. So, if you are intentionally trying to conceive, it is recommended to consider these periods in your cycle.

But knowing your high fertility and peak fertility windows is only half of the equation when attempting to conceive. An egg is only viable for up to 24 hours during ovulation, but healthy sperm can live in the female reproductive system for up to five days. So, if a woman engages in unprotected sex or is inseminated four to five days before the egg is released during ovulation, it may be possible to conceive.

The likelihood of conceiving depends on several factors beyond the fertility window, such as the quality of the egg and sperm. But in general, the figures below are a rough estimate of the typical likelihood of getting pregnant during the high fertility and peak fertility periods:

• 3 days before ovulation (high fertility) = 27%
• 2 days before ovulation (high fertility) = 33%.
• 1 day before ovulation (peak fertility) = 41%
• The day of ovulation = 20%

How to Improve Fertility

Some women are able to get pregnant fairly easily. However, some women try for years. It can be an incredibly frustrating and discouraging experience. So, what can you do about it?

On top of tracking the high fertility and peak fertility timeframes, keep in mind that there are other factors influencing fertility levels and chances of conceiving.

One of the biggest factors is age. Women have a fixed amount of eggs, called an “ovarian reserve,” which declines with age. The 20s is the optimal period of fertility, as a healthy woman in this age bracket has an average of 25% likelihood of conceiving naturally per month. This slowly declines to approximately 20% when a woman is in her 30s and about 5% in her 40s.

It’s best to talk to your doctor or OBGYN if you are intent on becoming pregnant. Approximately 80% of couples become pregnant within half a year of trying, and this rate increases to 85% after a year. For healthy couples, particularly women with regular menstrual cycles who have been attempting to conceive for 12 months, it is recommended to consult with your OBGYN.

On the other hand, women with irregular menstrual cycles or couples with possibly detrimental health conditions should consult with an OBGYN before trying to conceive. They can help evaluate your situation and optimize conditions for conception.

Women’s health is finally getting the attention it needs and deserves, and e7 Health National Testing is here to guide you. Rather than being completely in the dark, having data can help you more effectively plan your pregnancy journey. Our fertility tracking panel quantifies two of the most common fertility measures: progesterone and AMH (i.e., anti-mullerian hormone, which corresponds to your ovarian reserve). Order your panel online today!