A new study published in the journal JAMA Ophthalmology on October 8 is suggesting that firstborn kids might be at a slightly greater risk of developing nearsightedness later in their life compared to siblings born after them.

During the said study, researchers checked nearsightedness records and birth order of around 89,000 individuals aged between 40 and 69 years. They found that the firstborns taking part in the study were 10% more likely to develop nearsightedness than the later-born participants. Also, the study also revealed that the firstborn individuals had 20% greater chances of becoming severely nearsighted than the ones who were not their parents’ first child.

However, after adjusting the results of the study based on education levels, for instance, the highest educational degree obtained by the individuals taking part in the study, the researchers found that education made up around 25% of the association between birth order and increased risk of developing nearsightedness.

This finding indicates that parents might be more interested in the educational development of firstborn children. For instance, they might be spending more time completing home works and reading with their firstborn kids compared to the ones who were born later. The researchers conducting the study are saying that this in turn might mean that the firstborn children end up spending more time taking part in activities known for promoting nearsightedness.

Jeremy A. Guggenheim, a representative of the Cardiff University in the UK and one of the authors of this new study, said that the survey conducted by him and his colleagues has come up with an additional evidence to establish the association between education and myopia. He added that this revelation is consistent with the fact that countries where intensive education is common since a very early age have much higher prevalence of myopia compared to other parts of the world. For those who don’t know: people associated with the world of medicine refer to nearsightedness as “myopia”.

An earlier study involving 110,000 males aged between 15 and 25 years from Singapore revealed that astigmatism and severe myopia were more common in participants who had more years of formal education. Another study that had 1,900 Chinese children as participants, on the other hand, showed that the risk of developing nearsightedness can be reduced by spending more time outdoors.