Apparently, a growing body of research–gathered essentially as a by-product of other research into everything from pesticides and flu viruses to sunlight and vitamin D–suggests that the month a baby is conceived in can have serious health consequences later in life. Infants conceived in June appear to suffer from birth defects at a higher rate than others, for instance. But babies born in the fall (conceived in November or December) tend to have more asthma. Even a baby’s gender can be influenced by timing that’s out of parents’ hands: research has shown the birth of baby boys dips nine months after stressful world events such as Sept. 11.

As researchers busy themselves filling in this veritable new zodiac, parents-to-be wonder how closely they should study the calendar.

Check out some of the other weird correlations based on month of conception:

* Research out of Indiana suggested a link between American babies being conceived between April and July and a higher risk of birth defects, including spina bifida, cleft lip and Down syndrome.

* A study out of Bristol in Britain, released in February, found that late-summer and early-autumn babies in Avon were on average slightly taller (5 millimetres) and had thicker bones (12.75 centimetres squared) than those born in winter and spring.

* A team in Nashville found a 30-per-cent increase in the risk of asthma for children born four months before flu season, in late fall and winter.

* An Israeli study found that babies born in June and July had a 24 per cent greater chance of becoming severely myopic than those born in December and January.

* Many studies have found that babies born in the Northern Hemisphere in February, March and April have a 5 to 10 per cent higher risk of schizophrenia.

The full article can be found here.

– S.