If you’re looking to increase your chances of having a healthy baby girl, you might want to consider a summer delivery. According to a study published in the journal Heliyon, a woman’s overall healthy might be somewhat influenced by her month of birth.

Newsweek reports that researchers collected data from 450,000 men and women as part of the continuing United Kingdom Biobank project, which tracks health and disease trends in the country. The study determined that expectant mothers exposed to sunlight during their second trimester might be critical to fetal development. If we go back to elementary science, exposure to the sun helps produce vitamin Da key component to great health.

As a result, girls born in the summer weighed more than winter babies. They were also more likely to achieve a higher level of education, but scientists found no differences in regard to body mass index. "When you were conceived and born occurs largely 'at random'—it's not affected by social class, your parents' ages or their health—so looking for patterns with birth month is a powerful study design to identify influences of the environment before birth," study leader John R.B. Perry said in a statement to the press.

He added: "We think that vitamin D exposure is important and our findings will hopefully encourage other research on the long-term effects of early life vitamin D on puberty timing and health.”