The most incisive guide to issues facing the American family today . . . An invaluable resource for anyone wishing to stay on the cutting edge of research on family trends.

-W. Bradford Wilcox
Associate Professor of Sociology, University of Virginia 

The Two-Parent Difference—Evident in the Cradle

Bryce J. Christensen and Nicole M. King

Sociologists have known for some time that children who grow up in the care of both of their parents enjoy a decided advantage over peers who do not. A new Belgian study has now shown that the two-parent advantage manifests itself among remarkably young children. Even babies in diapers, it turns out, are decidedly better off if they live with both of their parents than if they live with just one.

Recently completed by researchers at Université Libre de Bruxelles, the new Belgian study analyzes the effects of parental separation on infants ages seven to eleven months. More particularly, the researchers explain that their “main objective was to assess the possible impact of parental separation family structure on certain aspects of somatic health in low-age children.”

The data for this new study were collected between 2006 and 2012 from 79,701 infant children of French-speaking Belgians availing themselves of the free preventative medical care offered to young children through the Office de la Naissance et de l’Enfance. Analysis of these data, the researchers report, “confirms the possibility that not living with both parents is an independent risk factor for the somatic health and psychomotor development of infants.” 

Deploying statistical models that take into account “social, economic, and cultural factors as well as . . . the age of the mother at childbirth and other potential confounders,” the researchers discern “a significant increase in the percentage of health problems in infants when the parents were separated compared with situations in which the parental couple was intact.”

More particularly, the Belgian scholars calculate an Odds Ratio of 1.3 for “a psychomotor delay . . . if there was parental separation.” That is, compared to a child in the care of both parents, a child whose parents were separated was 30% more likely to manifest symptoms of a psychomotor delay in development. The authors of the new study suggest that this differential in risk may reflect “the influence that the quality of both parents’ involvement in the upbringing of the infants has on the infants’ cognitive-behavioral development.”

Also worrisome for the researchers was the “strong association between parental separation and abnormal polysomnography results” (Odds Ratio of 1.8).  An 80% elevation in the risk of an abnormal polysomnography is especially troubling because an abnormal polysomnography predicts sharply elevated risk of Sudden Infant Death Syndrome (SIDS). The researchers offer no definitive interpretation of the linkage between abnormal polysomnography results and parental separation.  However, they do suggest that this linkage could derive from “the absence of exclusive breastfeeding” among mothers separated from the father of their child. After all, previous studies have demonstrated that a mother’s likelihood of breastfeeding her baby depends in part on her “marital status and of the presence of the infant’s father.”

Finally, at a time when pediatricians express increasing concerns about childhood obesity, the researchers note that infants whose parents had separated were 20% more likely to have a body mass index (BMI) above the 97th percentile than were infants in the care of both parents.

The Belgian researchers freely concede that their data do not give them grounds for offering any compelling “explanation about the reasons behind these observations” linking parental separation to health problems in infants.  However, these researchers do believe that their statistical analysis has largely accounted for economic differences, so compelling them to “step back from the idea that the less-than-optimal development of the children of separated parents is due only to an economically more precarious environment.”

In discounting the predictable economic explanation of why children in their study have suffered when parents part, the Belgian researchers recognize that they are not alone. They point to a nationwide American study showing “that, after adjusting for socioeconomic status, young people living in single parent or blended families suffered more often from oral, respiratory, or trauma-related problems significantly. What is more, these young people developed more adjustment disorders and difficulties at school, and required more specialized care” than did peers in intact families.

More broadly, the researchers interpret their own study and its American predecessor in the context of a raft of American and European studies concluding that parental separation exposes children to sharply increased risks of various problems—including severe infection, stunted growth, alcohol abuse, premature cardiovascular disease, depressed educational attainment, depression, and poor health habits.

In any case, the authors of this new Belgian study believe their findings are particularly urgent at a time when “many children are affected by the separation of their parents: 30 to 40% in the United States . . . and 25% in Canada  . . . . The situation is similar in Europe,” where recent statistics indicate that “in France, 3 million children were living with one parent,” while “in Belgium . . . there were 67 separations for every 100 marriages, . . . [with an] estimated . . .  500, 000 minors . . . affected.”

The researchers understandably conclude by asserting that if their findings are verified, they should have “a major impact on the actions of family doctors and other first-line healthcare providers, in particular with regard to information and targeted prevention.” But of course, in Boston as well as Brussels, in Anaheim as well as Antwerp, the real “targeted prevention” this study cries out for is that which prevents parents from separating. That prevention is called marriage, enduring marriage.

(Nadine Kaœnelenbogen et al., “Not Living with Both Parents Is Associated with More Health- and Developmental Problems in Infants Aged 7 to 11 Months: A Cross-Sectional Study,” BMC Public Health 15 [2015]: 159, Web.)