Is Mom's Diet a Key to Her Baby's Sex?
Researchers Question Findings of Study That Linked Breakfast Cereal to Delivery of Boys
Looking at the 'Big Picture'
Meanwhile, the study authors stand by their findings, noting in a reply to the criticism, also published online in the journal, that the U.S. scientists are overlooking their primary finding about the "big picture" dietary patterns of pregnant women.
"Mothers' intakes of a range of nutrients are linked with the sex of the infant," Fiona Mathews, DPhil, lecturer in mammalian biology at the University of Exeter, England, the study's lead author, tells WebMD in an email.
Mathews also says that the U.S. team "applied a nonstandard statistical method to the data from my work."
She points to two other studies, both published in 2008, that support the hypothesis that the maternal environment around conception may favor the survival of "girl" sperm (with X chromosome) or "boy" sperm (Y chromosome).
"One [study] looked at maternal weight change between pregnancies and found that women who gained more weight were more likely to have sons," she says. The other found that women with eating disorders that resulted in reduced calorie intake were less likely to have boys.
Two infertility specialists who reviewed the study and reanalysis for WebMD side with the U.S. researchers, although one says the "maternal environment" may influence gender.
The association between cereal and gender is "a random event," says David Adamson, MD, a fertility specialist in Palo Alto and San Jose, Calif., and immediate past president of the American Society for Reproductive Medicine.
Even if it is not a chance association, he says, it does not prove cause and effect.
Any link between cereal eating and the sex of the baby is a "random chance event," agrees Steven Ory, MD, a past president of the American Society for Reproductive Medicine and a fertility specialist in Margate, Fla.
"What we've learned about sex selection in the recent past is that it's ultimately determined by the father," he says, although he adds that there may be some factors in the mother's reproductive tract that may make it more likely for "girl" or "boy" sperm to meet the egg.
The best advice for mothers-to-be? Ory and others recommend a healthy, well-balanced diet before conception and during pregnancy. "I don't think there is any realistic hope that their cereal is going to influence the sex of their baby."