Around 3.5 million women in the UK take the birth control pill - that's about 25% of the entire population of women aged 16 - 29. But if you're one of them, have you found yourself becoming increasingly possessive or jealous where your partner is concerned? Do you, for instance, worry about whether or not they're being faithful, even when you have no real reason to?
Experts from Stirling University claim brands of the pill that have high levels of the hormone oestrogen may be to blame by making women more jealous.
According to their study, published in the journal Personality and Individual Differences, 275 women - all of whom were taking various different brands of the pill - were asked questions such as, 'How do you feel when your other half flirts with another woman?' and 'Are you worried your partner will leave you for someone else?'
The women who took the brands of the pill with the highest amounts of oestrogen gave the most emotionally-charged answers, the scientists claim. However, those who were taking progesterone-only pills weren't affected in the same way.
It's not the first time the pill has been associated with interesting side-effects, both positive and negative. For instance, a recent study suggested it could increase the size of women's brains, thereby boosting their memory and social skills. Other studies claim taking the pill could make you broody and alter your sense of smell, and even change your taste in men.
Do you take the pill? Has it affected your moods or emotions?
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