A new study published by the American Psychological Association indicates that the daughters of women who give birth at age 30 or later are more likely to experience symptoms of distress than the daughters of younger mothers. Sons felt no effect from their mothers’ ages, and fathers’ ages also did not affect the kids.

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According to the report in the Journal of Abnormal Psychology, the older the mother, the more adverse symptoms reported by the daughter. Compared to daughters of mothers under 30 at birth, girls whose mothers were 30 to 34 had higher levels of stress, while daughters of mothers over 35 had the highest levels of stress, depression and anxiety.

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Jessica Tearne, a doctoral student at the University of Western Australia and lead author of the study, proposed two hypotheses to explain the research. One is that there’s a larger generational gap between older mothers and their daughters, which could lead to tension in the relationship. 

“Older mothers may have more difficulty understanding or relating to the world their teen daughters live in,” Jill Weber, a clinical psychologist (who was not involved in the study) in Washington, D.C., tells Yahoo Parenting. “But it’s hard to imagine that variable alone would set them up for more distress.”

Tearne’s second theory is that older moms might be having health issues associated with aging by the time their daughters are teenagers, which could cause family strain — and daughters have been shown to be more affected by their mothers’ health problems than sons. 

Weber is skeptical of this idea, though: “It’s hard to imagine every person in the study’s mother had a health issue,” she says. “Fifty is not 80, so it’s likely some of these mothers were perfectly healthy.”

Weber notes that the study does not demonstrate that increased maternal age causes distress for daughters, but it does show that there is a correlation or relationship between the two. “There may be a third variable contributing here,” says Weber, noting that it’s possible that older mothers talk about or label emotions more than younger mothers, so the girls in the study could be more comfortable acknowledging their stress and anxiety. “Perhaps the daughters of younger mothers also have distress but are not as comfortable reporting it,” she suggests.

An alternate possibility, according to Weber, is that girls with older mothers may not feel as comfortable sharing experiences with their moms if they think they’re moms won’t “get it,” so they could choose to bottle up feelings, which creates more anxiety.

Another potential issue: “There may also be fertility struggles for the older mothers that lead to more protective or anxiety-prone parenting, which trickles down to the daughters,” says Weber.

The scientific summary of the findings notes that further research is needed. Monique Robinson, PhD, another author of the study, said in the news release, “It is important to remember, too, that the study examined symptoms of distress, rather than clinical diagnosis.”

(Photo: Corbis Images)

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