Follicular growth and corpus luteum function in women with unexplained infertility, monitored by ultrasonography and measurement of daily salivary progesterone.

Ovarian function was evaluated over a minimum of 3 consecutive menstrual cycles from each of 41 women with unexplained infertility. Follicular development and ovulation were monitored using real time ultrasonography and luteal function was evaluated by daily salivary progesterone measurement. In 129 spontaneous cycles, normal single ovulations were detected in 121 (93.8%). Luteal phase insufficiency was identified in 21 (17.4%) of these 121 cycles and this was a recurrent phenomenon in the cycles of 5 of the 41 women (12.2%). A successful pregnancy was seen only in association with consistently normal salivary progesterone profiles or where the empirical use of clomiphene citrate therapy had corrected previously diagnosed luteal phase insufficiency. Basal body temperature records or mid-luteal serum progesterone measurements were less satisfactory indices of luteal function than a salivary progesterone profile.