Egg release from the ovaries (ovulation) is controlled by a hormone called luteinising hormone (LH). LH levels noticeably rise about 24 to 36 hours before ovulation. By using a home ovulation test to measure the LH levels in their urine, women can find out the most fertile days of their menstrual cycle, and this can help them get pregnant.
Another type of home ovulation test involves testing saliva for subtle microscopic changes that occur during a woman's cycle. The test kit contains a magnifying lens that is used to examine samples of saliva, which changes appearance when the oestrogen level rises several days before ovulation.
Last Reviewed: 20 June 2008