If a woman is not ovulating by herself then ovulation induction may be required. The most common causes of failure to ovulate are stress, weight fluctuations and Polycystic Ovarian Syndrome (PCOS). Other causes may include disorders of the pituitary gland, thyroid gland and raised prolactin levels. In some cases failure of ovulation is due to the ovarian failure. This may occur following treatment for cancer or may be the start of the menopause – premature ovarian failure.
If a woman has an irregular menstrual cycle, monitoring with ultrasound scans (follicle tracking) and hormone assessments may help to identify the fertile time of the month and so improve the chances of natural conception.