by Kathy Sena
Have you consulted one of the increasingly popular online Chinese calendar charts to predict your baby’s sex? A University of Michigan epidemiologist recommends that you hold off on painting the nursery pink or blue. Eduardo Villamor, M.D., along with colleagues in Sweden and Boston, found that the “Chinese lunar calendar” method of predicting a baby’s sex is no more accurate than flipping a coin.
“We didn’t undertake this study with the goal of being myth-busters. We were just curious about it, really,” Villamor says. “But based on our results, I would not trust these predictions whatsoever.”
Villamor and his colleagues reviewed records of 2.8 million Swedish births, between 1973 and 2006, to test the accuracy of the Chinese lunar calendar method. The technique involves converting the mother’s age and the month of conception to dates on the Chinese lunar calendar, then plugging those dates into a chart that purportedly predicts the baby’s sex.
Conversion tables and Chinese birth charts are available on numerous websites and continue to grow in popularity. “The whole thing sounds pretty nonsensical. There is no information on the rationale behind the chart and we couldn’t think of a biological basis for it,” says Villamor. “Even though we were skeptical, we tried to keep an open mind, and we just analyzed the data to see if there is anything to it. There isn’t.”
Some of the Chinese lunar calendar websites claim accuracy rates of up to 93 percent. But when Villamor and his colleagues compared the Swedish birth records to the charts’ predictions, they found that the Chinese charts were correct about 50 percent of the time — the same accuracy rate you’d get from flipping a coin.
Kathy Sena is an award-winning health and parenting writer and the mother of a 14-year-old son. Visit her website at www.kathysena.com and check out her blog, Parent Talk Today, at www.parenttalktoday.com.
