Mood swings can also be traced to progesterone deficiency or an estrogen excess. Progesterone has a calming sedative effect on the brain. It attaches to a receptor in the brain that decreases anxiety and elevates mood. This receptor in the brain is called the GABA receptor. The GABA receptor is the same receptor Prozac and other antidepressant and anti-anxiety drugs use to produce their effect on the brain.
Insomnia is another frequent complaint of women during menopause.
The insomnia is probably due to the lack of the calming effects of progesterone. Replacing progesterone usually improves insomnia. Many women complain of poor concentration and lapses in memory during menopause. Progesterone is involved with providing insulation to nerve cells. Myelin which surround nerve cells, acts like rubber around electrical wires.