The luteal phase (or luteal phase of the menstrual cycle) refers to the time between ovulation and menstruation in women who are not pregnant and lasts about 12-16 days in healthy, reproductive-age women. It’s named after the corpus luteum (Latin: yellow body), the follicle that forms from ovulation and secretes progesterone and other hormones until it’s replaced by the lining of the uterus during menstruation.



Changes in Hormones

 

The most noticeable change in hormones during your luteal phase is an increase in progesterone levels. The second half of your cycle, from ovulation until you get your period, is also referred to as luteal for that reason. The main role of progesterone, which rises steadily and stays at a high level throughout your luteal phase, is preparing for pregnancy—if fertilization does occur and you become pregnant, it will help prepare your uterus for a possible embryo.

Changes in Cervical Mucus

 

The luteal phase starts with your period and ends with ovulation. Over a span of 14 days, your cervical mucus will change from thick, sticky and white-ish in color to thin, slippery and clear-ish. This is when it’s easiest for sperm to reach and fertilize an egg. If you are trying to get pregnant, you can monitor these changes and have sex during your most fertile time of day. If you aren’t trying to conceive, then you may want to avoid having sex during these times since sperm can live inside a woman’s body for up to five days after intercourse.

First Few Days of the Luteal Phase

 

At first, luteinizing hormone (LH) causes estrogen levels to rise. The increase in estrogen triggers an increase in follicle-stimulating hormone (FSH), which in turn induces ovulation about 14 days after menstruation begins. Your body temperature rises and you feel fertile. If pregnancy does not occur, estrogen levels fall and FSH is reduced, triggering a sudden drop in progesterone levels. This leads to the shedding of your uterine lining and bleeding that lasts for three to five days. This is known as the menses period or menstruation.

Middle Days of the Luteal Phase

 

Day 10-16 of your cycle marks what doctors call the luteal phase. This is when progesterone is highest, which makes sense because it’s responsible for preparing your uterus for implantation. For example, you’ll see an increase in cervical mucus as well as a warming sensation in your lower belly that may spread down through your pelvic region. Think of it like a little baby nest! If pregnancy doesn’t occur during ovulation, these symptoms will disappear and menstruation will begin. The length of your luteal phase can vary from woman to woman—some experience just a few days while others have up to 16 days—but most women are somewhere between 12 and 14 days long.

Last Few Days of the Luteal Phase

 

Throughout your period, you’ll have a natural drop in estrogen levels. Your follicle-stimulating hormone (FSH) and luteinizing hormone (LH) will also drop, causing a decrease in your ability to get pregnant as you get closer to ovulation. This is called fertile mucus, which tends to be very stretchy and clear or white in color—especially around day 14 of your cycle. If you want to conceive, it’s important that you have sex these days. By tracking your basal body temperature each morning with an at-home thermometer, you can pinpoint when these changes occur so that you can time intercourse accordingly.

Ovulation Problems

 

If you are suffering from infertility, there’s a chance your body is not ovulating—an egg is released by one of your ovaries during what’s called ovulation. A lack of ovulation means that an egg never gets released. To get pregnant, you must either be having sex at just the right time (within 12 hours before or after you think you’re going to ovulate) or have sex often enough to increase your chances of getting pregnant through sheer volume. If you aren’t ovulating regularly, see your doctor for help. Ovulation problems can usually be treated with medication and lifestyle changes.

The luteal phase (or luteal phase of the menstrual cycle) refers to the time between ovulation and menstruation in women who are not pregnant and lasts about 12-16 days in healthy, reproductive-age women. It’s named after the corpus luteum (Latin: yellow body), the follicle that forms from ovulation and secretes progesterone and other hormones until it’s replaced by the lining of the uterus during menstruation.