"Children born to older women have a better start in life," the Daily Mail has reported.
The news is based on the results of a large study of children born in England that looked at child health and wellbeing and the age of the mother. The research looked at children up to the age of five and assessed unintentional injuries and hospital admissions, immunisations, body mass index, language development and social and emotional development. The study found that increasing maternal age was associated with improved child health and development up to five years of age. This association was independent of how educated the mother was, family income or whether the parents were married – all factors that may have been expected to underlie the association.
Increasing maternal age is linked to increased risk of pregnancy and birth-related complications. However, this study has found that increasing maternal age may be linked to improved child health and development after the birth. Further studies are required:
It is important not to view the results of this research as evidence that older mothers are "better" at bringing up their children healthily. It merely finds an association between a mother’s age and some measures of health in their children.
The study was carried out by researchers from University College London, University of London and the University of California. It was funded by the Wellcome Trust. The study was published in the peer-reviewed British Medical Journal (BMJ).
The research was reported by the Daily Mail. While the overall tone of the coverage is largely accurate, there are several factual errors. For example, the number of children in the study is incorrectly reported.
The Mail also states that the researchers report that “older mothers tend to be more educated, have higher incomes and be married – all factors associated with greater child well-being”. While the researchers do state this, and it is true that these factors can be expected to underlie the association, the researchers also state that they adjusted for these factors in their analyses. In addition, the researchers included children who were part of the National Evaluation of Sure Start study, who were from the most disadvantaged areas (those in the lowest 20%).
This was a cohort study that aimed to investigate whether maternal age is linked to child health and development. It used data from two large British cohorts to see if there were associations between the age of the mother and several indicators of child health and wellbeing, while adjusting for personal and background characteristics.
A cohort study is the ideal study design to address this question. However, it cannot prove that maternal age is directly responsible for any associations seen. This is because, although the researchers have attempted to adjust for many factors that could be responsible for any association seen (called confounders), there could be others that the research has not been able to take into account.
The researchers used data from two large British cohorts:
The total sample included 31,257 infants aged nine months (18,552 from the Millennium Cohort Study and 12,705 from the National Evaluation of Sure Start). These children were followed up until they were five years old, with an additional assessment at three years of age. The number of children participating in the study was 24,781 at three years of age and 22,504 at five years of age. The age range of mothers was between 13 and 57 years.
The researchers collected information on indicators of child health and wellbeing, including:
The researchers then looked to see if there was an association between these indicators and the age of the mothers. They took into account several factors that may play a role in any association seen, including:
When the association between the age of the mother and body mass index (BMI) of the child was examined, the BMI of the mother was also taken into account.
The researchers found that a child’s BMI was not associated with mother’s age if the mother’s BMI was taken into account. However, a series of child health and development factors were related to the mother’s age. These were:
The researchers suggest that the lower rate of uptake in older mothers may have been due to the MMR scare.
The researchers conclude that: “In contrast with the obstetric risks known to be associated with older motherhood these results indicate that increasing maternal age was associated with children having fewer hospital admissions and unintentional injuries, a greater likelihood of better protection from ill health through completed immunisations by age 9 months, better language development and fewer social and emotional difficulties. The findings are noteworthy given the continued increase in mean age of childbearing”.
This study looked at the relationship between child health and wellbeing and the age of mothers in a large cohort of children born in England. It found that increasing maternal age was associated with improved child health and development up to five years of age. Health and development was assessed by monitoring a range of childhood health factors such as immunisations, hospital admissions and language development.
However, the study cannot show that maternal age was responsible for the associations seen. Although the researchers accounted for a number of factors that could have been responsible for the association, including education, income and whether the parents were married, the researchers could not exclude the possibility that there are other factors that are responsible.
Increasing maternal age is linked to an increased risk of pregnancy and birth-related complications, such as pre-term labour and congenital malformations. However, this study has found that increasing maternal age may be linked to improved child health and development beyond the foetal stage. Further studies are required to see if these differences are maintained as children grow older, whether there are other factors that could be responsible for the differences seen, and to establish why improved outcomes are seen in children of older mothers.