This is a hormone made primarily by the female ovaries. This hormone is also found in men in small amounts. This hormone plays an essential role in the body such as the brain, bone and heart health and many more. This is often the #1 hormone that becomes deficient when a female enters menopause. The ovaries decline its production and this can cause a host of menopausal symptoms such as hot flashes, nights sweats, insomnia and low libido.