Analysis of Human Vaginal Secretions by Gas Chromatography–Mass Spectrometry

Vaginal secretions from 14 ovulating females were analyzed by gas chromatography (GC) and gas chromatography‐mass spectrometry (GC–MS) during 50 ovulatory cycles. The day of ovulation was documented in each case by charting of basal body temperature and/or determining hormonal profiles for estrogens, progesterone and luteinizing hormone. The secretions were found to contain a complex mixture of acids, alcohols and aromatic compounds. Two distinct types of vaginal environment were found with six subjects displaying large amounts of C₂–C₅ aliphatic acids in secretions and the remaining showing only acetic acid by GC–MS analysis. Predominant concentrations of these acids occur both at midcycle and in the luteal phase of the menstrual cycle. Lactic acid and urea were present in the secretions of all subjects and underwent cyclic variations in concentration with maxima occurring around midcycle. The effect of sexual arousal on the organic compounds in the secretions is also discussed.