Regular ovulation is associated with regular menstruation. Women with irregular periods, occasional periods or no periods will often have an ovulation disorder. When a woman with an ovulation disorder is trying to conceive, she will usually require medication to induce normal follicle development and regular ovulation. For some women who already have regular menstrual cycles, e.g. in unexplained or poorly explained fertility, her fertility specialist may recommend ovulation induction in an attempt to increase the chance of pregnancy.