Cervicovaginal fluid changes to detect ovulation accurately

The purpose of this study was to evaluate changes in cervicovaginal fluid characteristics to identify ovulation. Several ovulation indicators were studied in a university-based natural family planning center. Fifteen parous women during 29 ovulatory cycles detected cervicovaginal fluid at the vulva. They self-aspirated their upper vaginal fluid, described it, and kept it for later checking. They also took basal body temperature, collected timed first morning urine samples for estrone and pregnanediol glucuronide enzyme immunoassays, and submitted to serial ovarian transvaginal ultrasound scans. Considering a ± 1-day period since ultrasound ovulation detection or allowing an extra day (−1 to +2), women perceived ovulation from cervicovaginal fluid at the vulva in 76% or 97% of cycles, on the basis of their visual description of vaginally extracted fluid in 76% or 90%, which rose to 90% or 97% for the instructor's description, and in 76% or 86% with a rapid drop in glucuronide ratio. Basal body temperature was less precise (71% or 79%). Evaluation of cervicovaginal fluid changes is an accurate ovulation indicator.