Using information on 18,000 children gathered over "an extended period of time," researchers from the London School of Economics say that kids born to first-time moms in their 30s have better cognitive scores and "behavioral outcomes" than first-born children with mothers aged 23 to 29

"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," lead author Alice Goisis said.