In a study by researchers of University of North Carolina reveal that women working night shifts have higher incidence of premature delivery. This links an external factor like night shift with movements in the uterus.The study shows that this factor can influence premature delivery by 50%.
The study studies and analysed the working conditions of 1,900 pregnant women. Additionally the study found standing for long periods and lifting heavy weights did not increase the risk of premature labour.
But working nightshifts in the first three months was linked to a doubling in a woman's risk of early labour.
'It would be premature to make recommendations to pregnant women about night work', said Dr Lisa Pompeii, University of North California
According to them this is possibly because they disrupt the normal activity in the womb at night.
The women who took part in the study were all interviewed in the seventh month of their pregnancy.
'The effects of night work needs more evaluation to confirm and establish any risk,' said Richard Warren, Royal College of Obstetrics and Gynaecology
The 9.2% of women (166) who worked nights were found to be at a 50% increased risk of giving birth early.
However, the researchers say the reason for the link is unclear, and the stress that because relatively few women in the study actually worked nights, particularly as their pregnancy progressed.