If your baby won't sleep through the night, don't blame the inconvenience on genes. That's the conclusion made by researchers in Italy who found that parents are largely in control of their toddler's sleep habits, reports the Los Angeles Times. Researchers in Italy reported the results of their studies of 127 pairs of identical twins and 187 pairs of fraternal twins in the journal Pediatrics. All of the parents interviewed for the study had babies 18 months old.
Between 25 percent and 30 percent of children and adolescents have sleep disorders. So the purpose of the study, the authors wrote, was to determine the contribution genes and environment play in sleep behaviors in early childhood. They found that identical and fraternal twins slept an average of 9.7 hours a night and napped for another 2.1 hours during the day. Fifty-three percent of them slept in the same room as their parents.
The Times reports that the child's environment, not genes, determined whether twins sleep in their own room or with their parents, but genes do play a role in whether they consistently wake up during the night. Thirty-one percent if identical twins woke up at least seven times a week and only 19 percent of fraternal twins did the same. About 31 percent of the variation in the length of time twins slept at night was explained by genetics, along with 36 percent of the variation in length of nap time, the Times reports.
The authors conclude: "Most sleep disturbances during early childhood are explained by common shared environmental factors, and behavioral interventions adopted by parents and focused on modifying sleep behavior could contribute to solving sleep disturbances in this age group." However, the authors add, "the influence of genetic factors should not be underestimated" and they suggest further research.