Hot flushes can lead to mood swings, sleep disturbances, and a decrease in overall quality of life. As oestrogen and progesterone fluctuate this impacts how the body's internal thermostat (hypothalamus) measures temperature, and so we become more sensitive to temperature fluctuations. This can cause sudden warmth or a flushed sensation in the face, neck, and chest. The body then tries to cool down by sweating excessively.