The widely believed notion that pregnancy and motherhood can cause women to be absentminded and forgetful, is false, says Professor Helen Christensen and colleagues at the Australian National University, as evident in the findings of the study of 1,241 women from 20 to 24 years of age.

The study tested their cognitive speed, working memory and immediate and delayed recall. After four years, the women were re-assessed, and again, after eight years. A total of 76 women were pregnant after follow-ups and an additional 188 became pregnant in between testing sessions.

The results show that there was no significant differences in their cognitive abilities and experts believe that neither pregnancy nor motherhood have an adverse effect on the women's cognitive capacity.

Part of the problem is that pregnancy manuals tell women they are likely to experience memory and concentration problems - so women and their partners are primed to attribute any memory lapse to the 'hard to miss' physical sign of pregnancy, says Prof Christensen.

In preparation for the birth of the new baby, pregnant mothers usually shift their focus away from the work issues, and new mothers selectively attend to their baby. Prof Christensen believes that the shift in attentional focus is adaptive. It certainly does not fall under the category of cognitive deficit.

She also advices that, Women and their partners need to be less automatic in their willingness to attribute common memory lapses to a growing or new baby.

It is about time that some research lays to rest this notion of pregnant women and the baby brain myth, says Cathy Warwick, the general secretary of the Royal College of Midwives.

Tiredness in both men and women can lead to loss of concentration which causes us to function less effectively, and this is the reason for the encouraged rest breaks pregnant women were allowed to take, at home and at work.

Many pregnant women will need this rest, and all of them deserve it.