INTRODUCTION

The uterine adnexa consist of the ovaries and fallopian tubes. The ovary consists of an outer cortex, where the ova and follicles are located, and medulla, where the blood vessels and connective tissue compose a fibromuscular tissue layer.

FUNCTION

By convention, the first day of menses represents the first day of the cycle (day 1). The cycle is then divided into two phases: follicular and luteal.

• The follicular phase begins with the onset of menses and ends on the day before the luteinizing hormone (LH) surge.

• The luteal phase begins on the day of the LH surge and ends at the onset of the next menses.

The average adult menstrual cycle lasts 28 to 35 days, with approximately 14 to 21 days in the follicular phase and 14 days in the luteal phase. There is relatively little cycle variability among women between the ages of 20 and 40 years. In comparison, there is significantly more cycle variability for the first five to seven years after menarche and for the last 10 years before cessation of menses.

In general, menstrual-cycle length peaks at about age 25 to 30 years and then gradually declines so that women in their forties have slightly shorter cycles. Changes in intermenstrual interval are primarily due to changes in the follicular phase; in comparison, the luteal phase remains relatively constant.