It is a sweet revelation for every mother-to-be.
Pregnant women have the perfect excuse to give in to their cravings - because chocolate is good for both mother and baby.
Expectant mums who regularly snack on chocolate bars are less likely to develop pre-eclampsia, according to a study.
One of the most common causes of premature birth in the UK, pre-eclampsia affects 70,000 British women a year and claims the lives of up to 1,000 babies and ten mothers.
It is characterised by high blood pressure and can cause convulsions, blood clots, liver damage and kidney failure.
But after asking 2,500 women about their dietary habits during pregnancy, researchers from Yale University in the U.S. found that those who consumed higher rates of chocolatey snacks - including hot chocolate drinks - were less likely to develop the potentially fatal complication, the journal Annals of Epidemiology reports.
It is thought that theobromine, the bittertasting chemical in cocoa, keeps blood pressure steady by helping blood vessels to dilate.
Researchers stressed the results may have been skewed by women being asked to remember what they had eaten during pregnancy.
The study also failed to examine if the benefits are confined to dark chocolate. Some research suggests milk or white chocolate does not have the same health benefits, as they they are higher in sugar and have a lower content of flavanols, the disease-fighting ingredient in cocoa used to make chocolate.
In a report on their findings researchers said: 'Women who reported regular chocolate consumption of more than three servings a week had a 50 per cent or greater reduced risk of pre-eclampsia.
'Regular chocolate intake during the first or third trimester was equally protective.'
Last year, Swedish scientists found heart attack survivors who snacked on chocolate at least twice a week could slash their risk of dying from heart disease by up to 70 per cent.
And in 2008, a team at Georgetown University in Washington DC discovered a chemical found in chocolate could hold the key to stopping bowel cancer in its tracks.
They tested a man-made version of the naturally-occurring ingredient and found it halved the rate at which tumours grew, while leaving healthy cells untouched.