Spinnbarkeit

Spinnbarkeit (English: spinnability), also known as fibrosity, is a biomedical rheology term which refers to the stringy or stretchy property found to varying degrees in mucus, saliva, albumen and similar viscoelastic fluids.

[1] Under the influence of estrogens, cervical mucus becomes abundant, clear, and stretchable, and somewhat like egg white.

The stretchability of the mucus is described by its spinnbarkeit, from the German word for the ability to be spun.

After ovulation, the character of cervical mucus changes, and under the influence of progesterone it becomes thick, scant, and tacky.

Mucociliary transport depends on the interaction of fibrous mucus with beating cilia.