The luteal phase of the menstrual cycle describes the time period from the first day after ovulation and ends during the first day of menstruation. The length of this phase can vary from woman to woman and sometimes from month to month within a woman's cycle, but it generally stays the same. The minimum amount of time the luteal phase will last is ten days, but it generally lasts 12 to 16 days. Levels and consistency of cervical mucus during the luteal phase can change, as cervical mucus changes throughout the menstrual cycle.
Just before and during ovulation, before the luteal phase, cervical mucus is abundant. It is likely that a woman will pick up cervical mucus when wiping her vagina with toilet paper during and just before ovulation. The consistency of the mucus at this point is very wet, clear, and slippery. It is often described as resembling raw egg whites and may be stringy. The amount and consistency of cervical mucus during the luteal phase, however, changes quite a bit.
Cervical mucus changes a lot following ovulation. During ovulation, the mucus is at its most fertile. It needs to be abundant and fluid in order for sperm to survive and travel all the way up the the egg. The mucus provides protection for the otherwise sperm-killing acidic environment of the vagina. During the luteal phase, however, the cervical mucus transitions to non-fertile.
During the first few days of the luteal phase, remnants of fertile cervical mucus are likely to be found. A person is likely to find a wide variety of colors and consistencies of cervical mucus at this point. Just after ovulation, fertile mucus may still be present, but the majority of the phase produces non-fertile mucus, which creates an acidic and inhospitable environment for sperm.
Cervical mucus during most of the luteal phase tends to be scant. At some points, depending on the particular woman's biology, there may be no traces of it to be found. If it is found, it will likely be in small amounts. During this phase, it is often described as dry, sticky, and thick. The coloring of the mucus generally changes from clear during ovulation to white during the luteal phase.
The changes in cervical mucus during the luteal phase are caused by changes in hormone production. Progesterone starts to be produced during the luteal phase, which is responsible for drying up the cervical fluid. If a woman is pregnant, it forms a sticky mucus plug that protects the growing fetus. Progesterone also warms body temperature for incubation if conception is successful.