The result should be seen in conjunction with the widespread recommendation not to have children too late. This recommendation is based on knowledge about e.g. declining fertility and the health risks during pregnancy and while giving birth which are associated with advanced maternal age.
"However, when estimating the consequences of the rising maternal age it's important to consider both the physical and psychosocial pros and cons," says Professor Dion Sommer from Aarhus BSS, who is one of the researchers behind the result.
Previous research has indicated that a higher maternal age is associated with increased psychosocial well-being during the pregnancy and the early days after the child is born. The new results indicate that the advantages for the older mothers and their children extend all the way into the children's school age, but decline before age 15.
Why do women postpone motherhood?
When today's mothers have children later in life than before, it is due to several reasons: We live longer, women have more educational and career opportunities, and contraception has improved. Today (2015), the average pregnancy age is an entire 30.9 years. This also means that most Danish children today are born when their mother is over 30 years old, and that the proportion of children whose mother was over 40 years old when they were born has quadrupled compared to 1985.
How does having an older mother affect the child's upbringing?
Older mothers are at greater risk of experiencing complications during pregnancy and while giving birth than younger mothers. They are at greater risk of having a miscarriage, giving birth prematurely and having children with deformities.
On the other hand, studies show that older women thrive better during the first part of motherhood. They worry less during the pregnancy, are more positive about becoming parents and generally have a more positive attitude towards their children.
Previous studies that have tracked children up until their school age indicate that children with older mothers - regardless of their parents' background, education and finances - have a better language and have fewer behavioural, social and emotional problems. This study tracked children of school age and found that children with older mothers had fewer behavioural, social and emotional problems at age 7 and 11, but not at age 15.
The reason is that older mothers have more stable relationships, are more educated and have obtained better access to material resources. But it is also interesting to look at the significance of age when these factors are removed from the equation. In such analyses, age can be interpreted as an indicator of psychological maturity.
"We know that people become more mentally flexible with age, are more tolerant of other people and thrive better emotionally themselves. That's why psychological maturity may explain why older mothers do not scold and physically discipline their children as much," says Professor Dion Sommer.
"This style of parenting can thereby contribute to a positive psychosocial environment which affects the children's upbringing," he concludes.
The study of the correlation between maternal age and children's social and emotional development was carried out when the children were 7, 11 and 15 years old respectively. The results have been published in the scientific journal European Journal of Developmental Psychology.
So far, many studies have examined the correlation between education, job or marital status and older mothers, while very few have looked at the significance of age in and of itself.