Editor's note: This column has been updated to provide attribution to original sources.

"Kids of older mothers are actually healthier, taller and highly educated than kids of younger mothers," claims a headline from The Health Site. The article is based on research by Mikko Myrskylä of the Max Planck Institute for Demographic Research and Kieron Barclay of the London School of Economics who collected data from more than 1.5 million Swedes born between 1960 and 1991. They examined the relationship between a mother's age when she had her kids, and certain attributes of those children, including height, fitness, and educational attainment.

The study showed that children born to older mothers were less likely to quit school, more likely to attend university, and tend to perform better on standardized tests than siblings who were born before them. Of course, younger children performing better than older siblings might be do with birth order. Many children who are younger benefit from having older siblings to learn from, so they learn social skills, language, and better habits at earlier ages. Children born to older mothers may also perform better because of advancements in health understanding or educational opportunities, allowing a child born in 2000 to have better outcomes than one born in 1980.

"Delayed childbearing may be desirable from a woman's own life-course perspective and beneficial for the child, especially among younger mothers for whom socioeconomic position and resources may be rising rapidly," wrote the authors.

Care.com, the caregiver and baby-sitter finding service, cited another study on the benefits of delayed motherhood. The article titled, The Perks of Delaying Pregnancy: Smarter Babies, suggests that the author believes delaying pregnancy causes smarter babies. (If she believes that, she's going to be disappointed...) The study analyzed women over 35 and found an association between maternal age and the child's cognitive ability.

"First-time mothers in their 30s are, for example, likely to be more educated, have higher incomes, are more likely to be in stable relationships, have healthier lifestyles, seek prenatal care earlier, and have planned their pregnancies," said researcher Alice Goisis to The Times.

Previous studies had different results, the authors wrote in the study, because "in the past, families in which children were born to older mothers tended to have larger numbers of children and were poorer than the average; whereas today these families tend to have smaller numbers of children and are socioeconomically more advantaged than the average, often because parents invest in education and become established in professional occupation before having children. Consequently, the association between advanced maternal age and childcare's cognitive ability might have changed over time."

Do women who are older have smarter babies or do smart women have babies later in life? If it's the latter then delaying children is not likely to produce smarter children - a better option would be to have children when resources are high (which is more likely as people are older, but not always). Also, having children later in life also brings other dangers - higher risks of miscarriage, autism, Down's syndrome, and childhood cancer.

(So, to avoid risks of a delayed pregnancy, the most reliable way to have smarter babies is to just have them with smarter people.)