Proton magnetic resonance of human cervical mucus during the menstrual cycle.

Cyclic changes in the human cervical mucus were observed as early as the middle of the 19th century and have in the last two decades been the subject of extensive investigations. Among other matters studied have been the macroscopic and general appearances (SEGUY and VIMEUX 1933) and the crystallization pattern (e. g. by PAPANICOLAOU 1945, 1946, by RYDBERG 1948, and by ZONDEK 1954). The amount of dry substance (BERGMAN 1950), the viscosity (LAMAR, SHETTLES and DELFS 1940), ‘flow-elasticity’ and ‘Spinnfiihigkeit’ (CLIFT 1945), and the amount of reducing substance (VIERGIVER and POMMERENKE 1946) have also been investigated. The studies have mainly been undertaken in order to correlate changes in the properties of the mucus with the time of ovulation, these being of considerable practical importance, especially for timing the optimal day of conception in cases of reduced fertility. In addition, changes in the cervical mucus are of considerable interest from theoretic viewpoints. I n the present study we briefly report some preliminary observations on the proton magnetic resonance spectra of the human cervical secretion in various phases of the menstrual cycle. Principles of nuclear magnetic resonance. Proton magnetic resonance spectroscopy is specific for the hydrogen nuclei in any chemical or physical state. The resonance or absorption line occurs in the radiofrequency part of the electromagnetic spectrum when a sample containing hydrogen nuclei is placed in a magnetic field of several thousand gauss; it is due to the elementary process of absorption of a low-energy electromagnetic quantum when a proton spin flips from a lower to a higher energy orien-