Researchers in Spain have found that 64 per cent of pregnant women suffer from insomnia in the third trimester of pregnancy.

The study, published in the European Journal of Obstetrics & Gynecology and Reproductive Biology, involved 486 healthy pregnant women. The effects of pregnancy on these women were monitored throughout all three trimesters The results revealed that 44 per cent of pregnant women suffer from insomnia in the first trimester of pregnancy, which increases to 46 per cent in the second trimester and 64 per cent in the third trimester.

These are very high figures which justify the need for a "systematic approach to this problem", according to the authors of the research. "Although it is well known that pre-existing sleep problems worsen and new issues frequently arise during pregnancy, there is a tendency to assume that difficulties related to getting to sleep and maintaining restorative sleep are characteristic phenomena of pregnancy and that must be endured," said one of the researchers Maria del Carmen Amezcua Prieto from the University of Granada.

But insomnia causes numerous problems. It affects the quality of life of pregnant women, which apart from being of great importance per se, is also a risk factor for high blood pressure and pre-eclampsia, gestational diabetes, depression, premature birth and unplanned caesarean sections. Consequently, the issue must be tackled systematically, the study said. Factors associated with insomnia were also analysed as part of the project.

"Although it may seem obvious, the most important factor is pre-gestational insomnia, given that it is fundamental to prevention and underscores the importance of detecting insomnia before pregnancy and throughout all stages of it," said Aurora Bueno Cavanillas of the University of Granada.

The study also revealed that other factors, such as obesity and whether or not the women have already had children, can have an impact on sleeping patterns. The findings suggest that regular practice of moderate or intense physical exercise during pregnancy protects women against pregnancy-related insomnia, "so this is yet another reason for promoting physical activity during pregnancy".