The contraceptive pill can impair a woman’s ability to read other people’s emotions and may affect her close relationships, a study suggests.

Research found that women taking the Pill were about 10 per cent worse at deciphering facial expressions that conveyed “complex” feelings such as pride or contempt.

The study found that the oral contraceptive may be blurring social judgement when it comes to discerning more subtle facial expressions.

Ninety-five women were challenged to look at black and white photographs of the eye region and select the best of four possible emotional labels that described the expression as quickly as possible.

Previous research has indicated that women on the pill are equally able to recognise more obvious expressions such as happiness or fear compared to those not on the contraceptive.

“Oral contraceptives impair the ability to recognise emotional expressions of others, which could affect the way users initiate and maintain intimate relationships,” said Alexander Lischke, of the University of Greifswald, Germany, who led the study.

More work should be done to explore the Pill’s psychological effects, he added. “More than 100 million women worldwide use oral contraceptives, but remarkably little is known about the effect on emotion, cognition and behaviour.”

The researchers recruited two groups of health.