There are several medicines available for correcting ovulation defects and the pregnancy rates after taking these varies from 50% to 85%. You should not worry, and after confirming the lack of ovulation, go ahead with clomiphene citrate 50mg once a day from the fifth day of the menstrual cycle (clomiphene citrate is one of the ovulation inducing medications) in consultation with your treating gynecologist. The ultrasound to check for ovulation needs to be done so that coitus can be planned at the best time for pregnancy to occur - with luck, sometimes 3-6 cycles of medicines are needed.