It also shields the fetus from chemicals that can deform their organs, The London Telegraph reported.

The study, published in the Proceedings of the Royal Society Biological Sciences, said morning sickness is usually accompanied by food aversions, most commonly to meats, fish, poultry and eggs — the foods that were more likely to carry harmful micro-organisms and parasites before modern refrigeration and food-handling processes.

The newspaper said the findings back a theory put forward six years ago by two Cornell University evolutionary biologists who suggested that morning sickness was beneficial to both mother and fetus.

Cornell biologists Samuel Flaxman and Paul Sherman said women who experience morning sickness are significantly less likely to miscarry than women who do not.