Menstrual Cycle

Natural ovulation cycles

Every month from puberty to menopause, an egg is released from a follicle within one of your ovaries. In natural ovulation, each month your ovary starts to grow several follicles, one of which becomes dominant.

Two hormones are responsible for the development of follicles within your ovaries:

• Follicle stimulating hormone (FSH), and
• Luteinising hormone (LH)

The cells in the follicles also produce oestrogen and progesterone. Your hormone levels will rise and fall at different stages of your monthly cycle. If the egg meets a sperm somewhere in your fallopian tube, fertilisation may occur. Once cell division begins, an embryo travels down the fallopian tube to your uterus, where it should implant in the endometrium. This typically happens about seven days after ovulation.