Cervical fluid is produced by your cervix as you approach ovulation due to increased estrogen. It flows from the cervix into the vagina where it can easily be observed. Your cervical fluid changes throughout your cycle, increasing in quantity and becoming more clear and stretchy as you get closer to ovulation.
In the most common pattern, cervical fluid starts out dry after your period and then gets sticky, then creamy, then wet and watery, becoming most like raw egg white as you get closer to ovulation. Usually it dries up quickly after ovulation. You may get different types of cervical fluid on the same day. Always record your most fertile cervical fluid to make sure that you do not miss a potentially fertile day.