A Historical Overview

The journey into understanding saliva's role in fertility tracking began in 1945, when Dr. George Papanicolau first noted microscopic crystal formations in cervical fluid. This phenomenon, known as ferning, is key to identifying fertile windows in the menstrual cycle.

Pioneering Research

In 1969, Dr. Biel Cassals, a Spanish gynecologist, extended this research to saliva. His groundbreaking presentation to the Barcelona Medical Board established that hormonal changes during the menstrual cycle influence the crystallization of saliva, which mimics the arborization effect seen in cervical mucus.

Hormonal Connections and Fertility

Estrogen, a hormone closely linked to fertility, modulates the salinity of saliva. As ovulation approaches and estrogen levels surge, so does the salinity in saliva. This increase causes saliva to crystallize in patterns similar to those in cervical mucus, which are detectable under a microscope.

How KNOWHEN works

FDA Approval and Clinical Validation

In 2009, the KNOWHEN® Advanced Saliva Ovulation Test received FDA clearance. Conducted by Dr. Hugh Melnick at the Manhattan Fertility Center, U.S. clinical studies affirmed the test's 98.9% accuracy. These studies demonstrated a significant correlation between the ferning patterns in saliva and actual ovulation, confirmed through sonographic examinations.

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Global Recognition

Today, Hilin Life Products, Inc. holds patents in numerous countries and is a recognized leader in fertility and reproductive health research.

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