If you feel more moody, sad, angry or just plain irritated in the days before your period is due, you’re definitely not imagining it.
Nine out of 10 women say they experience some premenstrual syndrome (PMS) symptoms, and mood swings and irritability are the most common.
Researchers still aren’t sure exactly what causes PMS, but changes in and interactions between hormones and certain brain chemicals are likely to play a key role.
But the hormones that control your menstrual cycle ebb and flow, meaning you’ll probably experience mood changes at other times of the month, too.
Here’s how you might feel during the four different phases of your menstrual cycle.
Phase 1: Menstruation
This phase kicks off on day one of your period, and typically lasts between three days and one week. Menstruation occurs when an egg hasn’t been fertilised, causing estrogen and progesterone levels to drop . Research shows it’s quite common to continue to feel a little down or experience mood swings during the first few days of your period.
Phase 2: The follicular phase
Technically, this phase also starts on day one of your period, so there’s a slight cross over with the menstruation phase.
It begins when your hypothalamus (a region of your brain) signals to the pituitary gland (also located in your brain) to release the follicle-stimulation hormone. This leads to a surge in estrogen that thickens the lining of your uterus .
If you have a 28-day cycle, this phase typically lasts for two weeks and once the first couple of days of your period are over, you might start to notice your energy levels increasing.
Plus, you might feel as if your brain’s sharper, so that you can remember and recall things more easily. Your tolerance for pain might be higher, too.
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Phase 3: Ovulation
The shortest phase of the cycle, ovulation only lasts between 16 and 32 hours, and is when you’re most fertile.
For many women, positive emotions and feelings peak at this phase of the cycle, perhaps thanks to the surge in luteinising hormone that’s required to trigger ovulation.
Phase 4: The luteal phase
This lasts for about 14 days and, as those days pass, you may start to feel a little sluggish and absent-minded, as well as irritable, sad, moody and even angry, as PMS well and truly kicks in.
One explanation for the mood-related symptoms may be that during the luteal phase, there is a drop in levels of serotonin, a brain chemical that’s sometimes called the “happy chemical ”. For most women, symptoms of PMS start between four and 10 days before menstruation begins.
If you experience PMS symptoms, including mood swings, and they bother you, increasing your intake of healthy fatty acids
and vitamin B foods
may help to turn the dial down.