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If you suffer from any of the symptoms that crop up before and during your period, you'll be happy to know that that time of the month isn't actually all bad.
As well as proof that your body is working properly, a recent study has suggested that women become "smarter" when they are at their most fertile.
Researchers at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig found that an area of the brain central to forming human memories, moods and emotions increased in size in parallel with increases in a key sex hormone.
As they studied the connection between hormones in women and severe mood swings, they discovered that rising levels of oestrogen enlarged the hippocampus.
Then, as oestrogen levels drop once the woman begins to menstruate, the brain area shrinks.
This increase and shrinkage happens with "astonishing regularity", the researchers reported.
The study aimed to gain a better understanding of a condition called pre-menstrual dysphoria disorder (PMDD) - a condition which is thought to affect one in 12 women.
Julie Sacher, a co-author of the study, said:
To get a better understanding of this disorder, we first have to find out which monthly rhythm the brain of a healthy woman follows.Only then can we reveal the differences in persons affected by PMDD.
To get a better understanding of this disorder, we first have to find out which monthly rhythm the brain of a healthy woman follows.
Only then can we reveal the differences in persons affected by PMDD.
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