Summer Babies Are More Likely To Have These Health Issues

Entering the world when it's hot and sticky, as it tends to be in the summer in the northern hemisphere, presents immediate challenges for a newborn, as their body has a harder time cooling off. "Babies cannot sweat, which is your body's way of cooling itself off, so they can often suffer heat stroke much quicker than an older child or adult," Dr. Jan Montague, director of pediatrics at Good Samaritan Hospital in Suffern, New York, told Parents.

What's more, overheated infants get dehydrated more quickly, and being​​ too warm has been linked to Sudden Infant Death Syndrome (SIDS). "Babies sleep deeply when they're hot, making them difficult to arouse, which may increase the risk of SIDS," Bruce Epstein, a pediatrician in Pinellas Park, Florida, explains to Parents.

However, it's not all bad news for those born in June, July, and August. In fact, there are health benefits to having a summer birthday. Here are some of the long-term health implications of being born amid the dog days.

The health challenges summer babies may face

A 2015 study of over 1.7 million people born between 1900 and 2000 and treated at New York-Presbyterian/Columbia University Medical Center investigated the link between a person's birth month and the diseases they developed throughout their life. The researchers found that the lifetime risk of 55 diseases was significantly correlated with the month in which a person was born.

One striking finding: Those born toward the end of summer are more likely to suffer from asthma later on than babies born in other seasons. The theory is that summer humidity is ideal for the proliferation of dust mites, which, through contact with infants, may lead to the development of asthma, Columbia magazine explains. The study also found that babies born in June had a higher incidence of "pre-infarction syndrome," an abrupt development or worsening of angina, which is a symptom of heart disease (via LiveScience).

Another study, published in the journal Ophthalmology, investigated what role birth season played in myopia, or nearsightedness. The researchers found there were seasonal variations in myopia, with the highest occurrence in people born in June and July. While the reason for this isn't clear, the study authors hypothesize it has to do with exposure to natural light during early infancy.

Health effects for baby girls in particular

One study out of the United Kingdom looked at nearly a half-million participants with the goal of determining the impact of birth season on such variables as birth weight, adult height, and body mass index. Another one of these variables was the age at which a girl had her first period. The researchers found that girls born in June, July, and August experienced later puberty.

The authors wrote that they've demonstrated a clear "association between season of birth and puberty timing in girls," but they're only able to speculate about the cause of the association. They suggested that it has to do with circulating levels of vitamin D, which have been tentatively linked to puberty timing. Furthermore, they believe that pre-birth levels of vitamin D (synthesized by exposure to sunlight) may play a role in when a girl enters puberty.

Overall, later onset of puberty is better for a girl's health than early onset. According to CNN, early female puberty leads to a higher risk of developing type 2 diabetes, obesity, and heart disease later in life.

The health advantages of having a summer birthday

Research shows that summer babies enjoy lots of health benefits — starting with birth. They're more likely to be born at a healthy weight than babies arriving in other seasons, according to a UK study. A healthy birth weight is generally between 5.5 and 8.8 pounds (via Medline Plus). A low or high bir​​th weight may be associated with a higher risk of death in the first year, as well as developmental problems developing in childhood and certain diseases in adulthood, a report in The International Journal of Epidemiology explained.

Summer babies are also less likely to develop Seasonal Affective Disorder (aka SAD), according to Reader's Digest, which may be due to the fact that summer sunlight helps newborns adapt to changes in the environment. Finally, the Columbia University researchers found that July was one of just two birth months (the other is May) that had no high-risk diseases to speak of. See, it's not all bad news for summer babies!