Pregnant women need vitamin D

The advice comes after doctors warned they were seeing increasing cases of rickets in young children as a result of vitamin D deficiency.

Rickets is a bone disease that was common at the start of the last century but was thought to be eradicated in the 1950s because of better nutrition. It can impair bone development leading to deformities as well as poor tooth formation, stunted growth and general ill health.

There have been several reports of a "resurgence" of rickets in recent years. In June 2007, doctors in Dundee said they had seen several cases and warned that guidelines on vitamin D for pregnant women were being ignored.

Vitamin D is made by the skin in response to sunlight, although it can also be found in certain foods.

Officials urged women to check if they were eligible for free supplements from their GP or health visitor under the government's Healthy Start scheme. The programme provides vitamin D-rich milk and fresh fruit and vegetables as well as supplements for those on benefits or women who are under the age of 18 years old and pregnant.

Most people in the UK should get enough vitamin D from sunlight - it only takes 15 minutes of sun exposure to the arms, head and shoulders each day during the summer months to make enough vitamin D for good health. But in winter months at latitudes of 52 degrees north (above Birmingham), there is no ultraviolet light of the appropriate wavelength for the body to make vitamin D in the skin, research shows.