This introduction discusses the aetiology of menstrual problems, their presentation and investigation as well as medical and surgical management. Specific problems such as fibroid-associated bleeding, adolescent and perimenopausal bleeding and breakthrough bleeding are covered, as are other critically important problems such as premenstrual disorders, pelvic pain and dysmenorrhoea. The most common presenting menstrual problem is heavy menstrual bleeding (HMB). A woman's approach to her periods will vary through her reproductive life. After childbearing is completed, the view of the menses will alter dramatically. The longest intermenstrual interval occurs at the menarche. Menstrual irregularity is most likely to occur at the extremes of reproductive life, the incidence of anovulation increasing as the menopause approaches. Classical primary spasmodic dysmenorrhoea occurs at the onset of the menses and gets better after 1 or 2 days, whereas secondary dysmenorrhoea tends to start prior to the menses and worsens as it proceeds.

Polycystic ovarian syndrome (PCOS) is one of the most prevalent endocrinopathies, affecting 5-10% of women of reproductive age. PCOS is one of the commonest causes of anovulatory infertility. The characteristic clinical features of PCOS include menstrual irregularity such as oligomenorrhoea and signs of hyperandrogenaemia including hirsutism, acne, and/or obesity. A recent study observed a significant and progressive correlation between body mass index (BMI) and both blood pressure and clinical features in women with PCOS. Clomifene citrate has been the standard treatment for induction of ovulation in women with anovulatory infertility for many years. The beneficial endocrinologic and morphologic effects of laparoscopic ovarian diathermy appear to be sustained for up to 9 years in most patients with PCOS. In vitro maturation (IVM) protocols are now a valuable alternative to conventional in vitro fertilization (IVF) as a strategy to prevent ovarian hyperstimulation syndrome (OHSS).