Nature's Gate

The cervical mucus acts like a gate. The gate is open when cervical mucus is flowing, and sperm can enter the uterine cavity. The gate is closed when mucus stops flowing and becomes a mucus plug that blocks sperm entry to the cervix, and thus the uterine cavity. 

Mucus Days or Fertile Days

When estrogen levels are high the mucus that is produced is called type E. Type E mucusn levels are high the mucus that is produced is called type E. Type E mucus arranges itself into strands call micelles. These strands are the channels along which sperm flow through the cervix. Type E mucus has an alkaline pH, which is ideal for sperm survival. Type E mucus is produced in large amounts so that it coats the surface of the normally acidic vagina turning it alkaline. In this manner sperm can survive their trip to the cervix. Type E mucus nourishes the sperm along its journey. Type E mucus is easily noticed at the vulva as clear, stretchy, or lubricative mucus – Peak mucus. Type E mucus may mix with material from the vaginal walls (vaginal cell slough) to produce a tacky, sticky, white mucus – Non-Peak mucus, that may create a smooth sensation at the vulva.

Of the 500,000,000 sperm present in a normal ejaculate only 20,000 to 100,000 will actually ever reach the ovum to attempt fertilization. They remain in the cervical crypts where E type mucus is present, or in crevices in the uterine cavity to await ovulation.

Dry Days or Infertile Days

Type G mucus creates an acidic vaginal environment and is hostile to sperm. Type G is thick and gelatinous, acting as a physical barrier to sperm trying to gain entry through the cervix. If any sperm manage to make their way to the cervix in the presence of Type G mucus they would find Nature’s gate closed.

When the gate is open conception is possible. Therefore, key to understanding days of fertility or infertility is learning to detect when the gate is closed and when it is open. This is done by observing for the presence of cervical mucus.