How Your Baby’s Birth Month May Affect Their Health


I grew up with four brothers who were all born in the month of April, in fact the first 10 days of April, were filled their birthdays. Till date, even if I get the dates mixed up, it would not matter, they always tell me, whose birthday it was and the closeness of the date also means, I never forget.

On the other hand, their mom was constantly teased for having the maths pat down about how to have babies in the month of April. Only the girls had different birthdays; one in May and the other in October. Back then, it made planning birthdays, a lot easier, as all the boys could celebrate theirs with whoever was having the main party or their mom could just say, the party was for all of them. Sometimes, they minded not having individual parties and at other times, it did not matter.

I had thought these family friends were special, however, I have become friends with someone, whose entire siblings, seven of them were all born in December. When I first heard this, I was surprised, and then glad that they were all born in my birth month. Now, this is what you call getting the maths of having a December baby pat down. I constantly tease him about their mom being a master December mom.

With these two set of families, I have noticed that sharing same birth mom brought a level of closeness, because they were mostly similar in personalities and by first hand experience, at least with the first family, they always complain about same health issues.

Take for instance, while the boys were younger, they were prone to having this condition that made their eyes reddish, watery and they always had headache. Neither of their sisters had this condition but the boys kept trading it back and forth, and no, it was not what you would call conjunctivitis. Their mom used to take them to the hospital, until she got tired and the doctor advised that, it would most likely clear up as they get older. It indeed stopped with the rest of the boys but not the older one, who still gets this condition periodically.

So, what has their birth month got to do with anything? The doctor had told their mom then that they were most likely experiencing similar conditions, because they were susceptible to it, as a result of being born in the same month. After all, if it were to be an infection, the sisters, with whom they shared things at home would have gotten it, and other children like myself would have gotten it. But no, the four brothers were the only ones with their red and watery eyes, every other month.

As it were, the doctor was just not saying things, he had spoken based on facts that several studies have since backed up. “The scientific literature goes back almost 100 years linking birth season to almost anything under the sun, from income to life expectancy to height,” says Hannes Schwandt, PhD, an economist at Princeton University’s Center for Health and Wellbeing. But Schwandt cautions that much of the research on this topic has not taken into account factors like the mothers’ socioeconomic status or the length of pregnancy—both of which can affect when a woman gives birth, as well as the health of their baby.

A more recent research by the University of Cambridge found that babies born in June, July and August routinely have the heaviest birth weights and have taller heights as as adults. While other studies have found correlations between size and birth month before, this is the first study to also link puberty to birth month, an important marker of adult health.

Specifically, baby girls born in the summer months tend to get their periods slightly later in life, which is indicative of a healthier adulthood. As early puberty has been linked to an increased risk of breast cancer later in life.

According to the lead author of the study, Dr. John Perry, “This is the first time puberty timing has been robustly linked to seasonality. We were surprised, and pleased, to see how similar the patterns were on birth weight and puberty timing. Our results show that birth month has a measurable effect on development and health, but more work is needed to understand the mechanisms behind this effect.”

While science and scientists are working things out to understand the full extent of the birth month/future health relationship of a baby. Here are their current knowledge concerning the months and the susceptibility of babies born in these months to certain diseases and conditions.


June, July, and August (Summer months)

As stated earlier, “women born in summer had higher birth weight and later puberty, which are both early life factors that have been linked to better health outcomes in adults,” says Ken Ong, programme leader at the Medical Research Council Epidemiology Unit, University of Cambridge, same study centre as the last one on the same subject matter.

May, June, July, August, and September

According to science, it had been discovered that women born during these months were more likely to be less fertile than women from other months. As I said earlier, its just science and might not really be true for all the women born in these months.

October, November, December ( The last three months of the year)

Babies born in the latter part of the year might have a harder time paying attention. Attention Defiency (ADHD) incidence tends to increase as the year goes on, with November babies being the most likely to experience the disorder.

People born in November and October are also more exposed to risks of reproductive, respiratory and neurological illnesses. However, babies born in December showed no increased risk to or protection from these diseases, so it could swing either way.

While that might seem quite daunting, people born in September, October, and November experience much less risk of cardiovascular disease.

January to June ( The first half of the year)

People born in the first half of the year might want to watch their cholesterol and sodium intake as they are at a higher risk of cardiovascular disease, with those born in February, March, and April at even higher risk. And on the up side, babies born in these three months are much less likely to experience neurological problems.

That is the extent of knowledge for now and while some of it were scary, it is still not the gospel truth as the scientists themselves noted that there were other variables at work in a baby’s life and future health apart from its birth month. “Unless you have a personal preference, there is no ‘best’ or worst’ month to get pregnant or have a baby. Any effects birth month has on a child’s health won’t be nearly as important as other factors you can control, regardless of the time of the year; like eating well, avoiding cigarette smoke and alcohol, and getting regular exercise while you are expecting.” says Schwandt.

Now, the ball is firmly in your corner, you can conceive when you want to and have the baby, when it’s ready to come. Much like folks for generations have been doing.

That’s something to chew on.



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