OI is method of treatment used for women who either don't ovulate (release an egg) or don't ovulate regularly. Fertility drugs (tablets or injections) are used to help women to ovulate and so that they have the chance to conceive naturally. The most common groupings include drugs, which work on the brain, drugs which stimulate the pituitary gland and those which act directly on the ovaries themselves.
The woman's natural cycle and follicular tracking (ultrasound monitoring) are used to help assess the day of ovulation and couples are then advised the best time to have intercourse.
The medications can result in up to 60% of ovulation.