Not Superstition: Science Explains Why Children Born in September and October Tend to Be Smarter

Scientists have conducted statistical research and found that children born in September and October often have higher IQs.

In traditional beliefs, our ancestors often referred to the term “favorable birth season” to describe people born at a time in harmony with nature, believed to result in good health and intellectual development. Interestingly, it's not just folklore that supports this idea—modern scientific studies have also shown a correlation between birth month and a child's cognitive development. In particular, children born in September and October tend to have significant physical and intellectual advantages in their early years.

What Does Science Say About Children Born in September and October?

A study from Harvard University (USA) tracked over 10,000 children for seven years. The results showed that children born in September and October had higher average IQs than those born in other months. Moreover, these children also had higher average birth weights, indicating a favorable start in physical development.

Additionally, statistics show that many famous athletes—especially American football players—were born in these two months. This has led researchers to question whether birth month could influence a person's overall development.

Supporting Statistics from China

Not only in the U.S., but a study conducted at Fudan University (China) yielded similar findings. It showed that among first-year university students, those born in October made up the highest percentage. Zhejiang University and Xiamen University also reported a significantly higher number of first-year students born in October. These numbers further suggest that being born in September or October may offer a head start in intellectual and academic development.

Why Are September and October Considered “Favorable Birth Months”?

To understand this, we need to look back to the time of conception for children born in September and October—which typically occurs in the spring. Spring is a season of renewal and growth, with mild weather and harmony in nature. During the early stages of pregnancy, spring provides mothers with a more relaxed and comfortable environment, free from the harsh extremes of summer heat or winter cold. This contributes significantly to fetal development in the first trimester—a critical period for brain and body formation.

Favorable Environmental Conditions for Mother and Baby:
Another benefit is that the final stage of pregnancy falls in autumn—a time of mild weather, not as hot as summer and not yet cold like winter. This makes it more comfortable for expectant mothers and reduces health risks during labor.

When babies are born in September or October, about three months later they begin to roll over, crawl, and explore—key developmental milestones that usually happen in spring. Thanks to the pleasant spring weather, babies are not restricted by heavy winter clothing, allowing for freer movement. They’re also not hindered by the intense heat of summer, enabling more outdoor activity.

This freedom of movement during a critical stage of development is essential for stimulating brain growth, helping babies become more agile and intelligent.

Important Note for Parents

While research and statistics show that children born in September and October may have certain advantages, birth month is not the sole factor determining a child’s intelligence or destiny. A person's intelligence and success also depend on many other factors such as:

• Genetics

• Nutrition

• Living environment

• Quality of education

• Love and attention from family

Therefore, if you are planning to have a baby, there’s no need to stress over timing the birth for September or October. What matters more is being well-prepared—financially, physically, emotionally, and in your knowledge of child-rearing.

The notion that children born in September and October have developmental advantages is supported by both modern science and traditional wisdom. However, every child is a unique individual with distinct potential, and parents can foster their child's intelligence by providing a nurturing educational environment.