Research by a North-East psychologist has challenged the common belief that pregnant women suffer from memory and concentration impairment.

A study by Dr Ros Crawley and her team at Sunderland University concluded that there was no evidence to support widespread opinion that women's mental abilities weaken during pregnancy.

Magazine articles, childcare books and even midwives have all contributed to such a belief.

To challenge this, Dr Crawley measured the performance of 15 pregnant women and 14 non-pregnant women.

They were tested on verbal memory, divided and focused attention, twice during pregnancy, and at six and 12 months after birth. Both groups were also asked to rate how they felt their memory and attention had changed.

Although the pregnant women felt that their memory and attention were worse than before they became pregnant, the performance of the two groups was the same.

The research has led to three possible conclusions. Either, the women are mistaken and the perceptions are caus-ed by negative mood swings, or cultural expectations of impairments, which make women more aware of forgetting and lead them to attribute mistakes to their pregnancy.

Or, their perceptions may reflect very mild impairments that are difficult to detect on standard laboratory tests - something Dr Crawley and her team plan to investigate in the near future.

Dr Crawley said: "The research generally addresses what pregnant women think about changes in their cognition and whether this has any basis in their performance.

"The message we want to get across is that although it's common for women to believe that there are changes in memory and cognition during pregnancy, the evidence from the tests used in this research does not support this."

Dr Crawley's findings are published today in the medical journal Psychology and Psychotherapy: Theory, Research and Practice.