Ovarian ultrasonography highlights precision of symptoms of ovulation as markers of ovulation.

Difficulties in assessing the exact time of ovulation have impeded investigation of the accuracy of symptoms of ovulation as indicators of ovulation. However ovarian ultrasonography has recently been shown to allow accurate observation of Graafian follicular growth up to the day of ovulation. This study investigated the menstrual cycles of 6 normal parous women ages 25-42 years who had been trained in observing ovulation symptoms for natural family planning purposes. These women recorded cervical mucus characteristics basal body temperature and other subjective data. In 9 of the 11 cycles for which luteinizing hormone concentrations were recorded there was a single peak value that coincided with the day of ovulation. The day of most abundant fertile-type mucus also accurately pinpointed ovulation. The last day of fertile-type mucus previously considered the most accurate marker of ovulation occurred 1-2 days after ovulation in 8/12 cycles and on the day of ovulation in only 4/12 cycles. The day before the rise in basal body temperature coincided with ovulation in 8 cycles but occurred later in the rest. The last day of periovulatory pain was the most insensitive marker analyzed occurring from 2 days before to 2 days after ovulation. These findings suggest that women can accurately pinpoint the day of ovulation by identifying the day of most abundant fertile-type mucus. Since the last day of fertile-type mucus occurred on or after the day of ovulation in all cases this day can serve as a reference point for identifying the beginning of the postovulatory infertile phase.