Pregnant women who work more than 40 hours a week and are on their feet a lot may give birth to smaller babies, according to a new study.
The research, published in Occupational and Environmental Medicine, shows that women who did jobs like teaching, childcare or sales where they spent a lot of time on their feet gave birth to babies whose heads were an average of one centimetre smaller than average at birth. Those who worked long hours also had lighter babies.
Women who worked more than 40 hours a week had slightly smaller babies than those who worked less than 25 hours a week. But there were no differences in incidence of preterm delivery, low birth weight or babies being born too small for their gestational age, according to the study which was led by Dr Claudia Snijder of the Erasmus Medical Center in Rotterdam.
The differences in head size and weight were noticeable in the third trimester, but it is unclear whether this has any long-term effect on a baby’s development.
The researchers also asked women whether they did night shifts and were involved in heavy lifting. They suggest their findings show a need for limits to be placed in the third trimester on shift work, night hours, standing, lifting and noise.