These imbalances
create cysts to form on the ovaries, causing
irregular menstrual
cycles, infertility, cardiac disease, and physical changes such as increased hair growth.
Building on the work of other scientists who had observed that the Earth's orbit around the Sun was
irregular in three particular aspects, Milankovitch
created a model to show how the amount of sunlight (solar radiation) reaching the Earth varied according to the interaction of the
cycles of these three irregularities, which are described below: