The season at which a baby is born or conceived seems to impact their health, with a new Finnish study suggesting that children conceived in early spring are more likely to develop food allergies. Lead researcher Dr. Kaisa Pyrhonen suggested this could be because of an increased pollination in spring, exposure to sunlight (related to vitamin D synthesis) and viral infections. Still, families shouldn’t plan pregnancies around specific times they said, because it was only an observational study. In it, the team looked at 5,920 Finnish children born between 2001 and 2006. From birth to four years old, 961 were tested for food allergies; up to the age of 4, the chances of having one varied according to when they were born, from 5 per cent for those born in June and July, to 9.5 per cent in October and November. A child whose first three months of fetal development ended in April or May were three times more likely to be allergic to milk and eggs than those who reached the stage in November or December. Past studies have shown that babies born in autum and winter are more likely to have eczema and asthma.