Ovulation can be diagnosed by all except:

Method to document ovulation Feile window : it is the 6th day interval ending on the day of ovulation but not after ovulation. Basal body temperature : ovulation is assumed after 3 consecutive days of raised temperatures. It involvew daily recording of oral or rectal temperature using a BBT thermometer before the patient arises,eats or drinks. The secretion of Progesterone following ovulation causes a temperature increase of about 0.5-1 degree F over the baseline temperature of 97-98.8 degree F that is typically recorded during the follicular phase of menstrual cycle. It produces a characteristic biphasic pattern in women with ovulatory cycles. Limitations : inability to prospectively predict ovulation and its frequent false negative results. Smoking and irregular sleep patterns can interfere with accurate testing. Cervical mucus : around ovulation the secretions are slippery and clear and volume of cervical mucus peaks 2-3 days around ovulation. LH monitoring : Once the LH surge is detected, ovulation may occur within next 48 hours. Mid Luteal serum progesterone : level above 3 ng/ml typically confirms ovulation. ultrasound monitoring : ovulation is charectarised by decrease in the size and crenated margins at the site of monitored ovarian follicle and appearance of fluid in the cul de sac. Reference: Novak's Textbook of gynaecology 15th edition page no 1151