The amount and thickness of cervical mucus decreases just before a period until it can no longer be felt, according to the UNC School of Medicine. This represents the lowest fertility window.
Cervical mucus types 1 and 2 occur right before and during a period. This type of mucus is present in scant amounts and is either not felt or feels slightly damp to the touch. Type 3 mucus appears closer toward ovulation and looks thick, whitish and creamy. It is typically not stretchy but can be sticky and feel wet to the touch. Type 4 cervical mucus represents the period of highest fertility and occurs around ovulation. It feels wet, slippery and smooth. It looks like raw egg whites and can be white, transparent and even reddish, explains the UNC School of Medicine.
Recording cervical mucus changes is an important way of tracking ovulation cycles. Thick, stretchy mucus typically represents the period of highest fertility, while its absence or the feeling of scant dampness represents the lowest fertility in a cycle. Cervical mucus should not be recorded during menstruation because it is difficult to differentiate if from menstrual blood, according to the UNC School of Medicine.
It is important not to confuse other reproductive fluids with cervical mucus. Arousal fluid is produced by vaginal glands during sexual intercourse and appears during sexual activity but quickly dissipates within one hour. Seminal fluid is released by the male during intercourse and can mimic the appearance of cervical mucus. It generally dissipates within 24 hours after intercourse, notes the UNC School of Medicine.