The Ovulatory Cycle

Ovulation is the central event of the ovarian cycle. It is followed after a time of about 2 weeks (can range from 11 to 16 days) by menstruation.  The behaviour of the reproductive organs during the ovarian cycle is controlled by several hormones, in particular the pituitary hormones (follicle stimulating hormone and luteinizing hormone) and the ovarian hormones (oestrogen and progesterone). This behaviour is captured in the following animation. There are two simulated fertile cycles, in the first cycle pregnancy does not occur, in the second cycle pregnancy occurs.

Familiarise yourself with the female reproductive organs as shown in the diagram below, then click here to load and run the animation.