A study recently conducted in the United Kingdom suggests that women who were born in the summer months are more likely to become healthy adults. One theory is that more sunlight exposure, and thus more Vitamin D, during the second trimester of a pregnancy could explain how a woman's season of birth produces physiological differences such as a heavier birth weight, taller height, and later start of puberty.
The study's findings were published in the journal Heliyon. It was conducted by researchers at the Medical Research Council (MRC) Epidemiology Unit, at the UK's University of Cambridge.
Researchers examined data on about 450,000 men and women who participated in the UK Biobank study. It revealed that a female infant's season of birth affected two key factors that influence an adult woman's general health: birth weight and start of puberty.
The environment that the fetus experiences in the womb has major effects on the early development of a person, known as "programming." It continues as a child, teen, and adult.
The Cambridge researchers learned that children born during the summer season had noticeable differences from those born during the winter season. Their birth weight was a little heavier, they were taller adults, and started puberty a bit later.
Lead author Dr. John Perry explained that the study's design was powerful. That is because birth months are not related to factors such as social class or parents' ages, according to Pioneer News. He explained that this is the first study that linked a person's season of birth to the start of puberty, according to EurekAlert!
Perry explained that more research is necessary. That could include investigating the long-term impact of early life Vitamin D on puberty timing and general health.
The Centers for Disease Control and Prevention (CDC) report that the most births in the United States usually happen in August. February has the least number.
This video explains the health benefits and risks of sun exposure: