A new study has revealed that girls born in summer are more likely to have higher birth weight and late puberty.
According to researchers at University of Cambridge, more sunlight, which is higher vitamin D exposure, in the second trimester of pregnancy could explain the effect.
They found that children who were born in the summer were slightly heavier at birth, taller as adults and went through puberty slightly later than those born in winter months.
In the study, lead author John Perry and the team compared the growth and development of around 450,000 men and women from the United Kingdom and found that babies born in June, July, and August were heavier at birth and taller as adults.
The study also revealed that girls born in the summer started puberty later which was an indication of better health in adult life.
Perry said that this was the first time puberty timing had been robustly linked to seasonality, adding that their results showed that birth month had a measurable effect on development and health.
According to the researchers, the differences between babies born in the summer and the winter months could be down to how much sunlight the mother gets during pregnancy, since that in part determines her vitamin D exposure.
Perry concluded that vitamin D exposure was important and their findings would hopefully encourage other research on the long-term effects of early life vitamin D on puberty timing and health.
The study is published in the Journal Heliyon.