ferning test

ferning test /fur″ning/ [AS, faern, fern; L, testum, crucible] , a technique used to determine the presence of estrogen in the uterine cervical mucus. It is often used to test for ovulation. High levels of estrogen cause the cervical mucus to dry in a fernlike pattern on a slide. Also called arborization test.

Ferning (McKee, 1997)