The Luteal Phase

The Luteal Phase is the time period beginning with the day after ovulation and running through the remainder of your menstrual cycle (it ends the day before your next period). Typically, the duration of the luteal phase phase lasts between 10 and 16 days - and is generally consistent from cycle to cycle, averaging for most women at 14 days.

In the Trying to Conceive (TTC) Community, the luteal phase is also referred to as "DPO" - or days past ovulation. At the onset of the luteal phase, women's body temperature increases (Basal Body Temperature) in order to provide a fertile environment for the ovum - and the uterus undergoes physiological changes that support implantation and fetal development.

The Luteal Phase in the Menstrual Cycle

At the beginning of the menstrual cycle, the body begins to produce follicle stimulating hormone (FSH). FSH facilitates the formation of a follicle on one of the ovaries. The follicle contains and nurtures the egg. When a follicle has adequately matured, a surge of luteinizing hormone (LH) causes the follicle to burst and release the egg into the fallopian tube - ovulation. At this point, fertilization of the egg may take place.

Once the follicle expels the egg, the follicle is called a 'corpus luteum'. The corpus luteum is responsible for producing the hormone progesterone - and during the luteal phase, progesterone facilitates a thickening of the uterine lining and the development of blood vessels, which gives the embryo a place to attach. During the luteal phase, the corpus luteum will produce progesterone for approximately twelve days.

Return to: Understanding Your Menstrual Cycle

Read More About:
The Dynamics of Conception and Fertility:
What Happens During Ovulation?
Learn About: Reproductive Hormones and Fertility