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A.Pre-eclampsia is a potentially serious condition that only occurs when you are pregnant. It causes high blood pressure and upset to your kidneys, which results in protein leaking into the urine. The severe forms occur in only around 2% of pregnancies but milder forms, usually with only a modest elevation of blood pressure, occur in around 5-10% of pregnancies. The cause of pre-eclampsia is unknown. The primary problem appears to be abnormal implantation of the afterbirth into the mother's womb. Doctors don't really understand why this problem with the afterbirth occurs. But it triggers a whole cascade of problems that upset the function of the blood vessels resulting in high blood pressure. Recently it has been found that the likelihood of developing pre-eclampsia is highest in mothers delivering their babies in the winter months and lowest in the summer. Doctors don’t yet know why this occurs. It might be because cold weather affects the function of the blood vessels. Alternatively it might be because something present in the springtime, such as in the diet, during the early stages of pregnancy influences the development of pre-eclampsia later in pregnancy in the winter.

Eating fish in pregnancy can reduce the risk of complications

Faroe Islanders, who have a diet rich in fish, tend to have pregnancies that last longer and have bigger babies compared to women who eat very little seafood.

This led a research group in Denmark to investigate whether the amount of seafood a woman eats in early pregnancy could affect the outcome of her pregnancy. They asked almost 9000 pregnant women how often they ate fish or took fish oil supplements in their pregnancy. They found that the more fish a woman ate the less chance she had of premature labour or a low birth weight baby. Premature delivery of the baby was almost 4 times more common in the women who did not eat any fish compared to those with the highest consumption of fish. The same was true for the likelihood of having a low birth weight baby. These results agree with previous research that found fish oil supplements in pregnancy could reduce the chance of premature delivery. So fish is a valuable component of a healthy diet in pregnancy.

*Reference: Olsen and Secher BMJ 2002; 324:447.