CHICAGO (Reuters) - Nearly a third of U.S. parents know surprisingly little about typical infant development, and this lack of understanding can rob their babies of much-needed mental stimulation, researchers said on Sunday.

A man and his baby wait outside at a rally for Pope Benedict XVI at St. Joseph's Seminary in Yonkers, New York April 19, 2008. REUTERS/Lucas Jackson

“There are numerous parenting books telling people what to expect when they’re pregnant,” said Dr. Heather Paradis of the University of Rochester Medical Center in New York.

“But once a baby is born, an astonishing number of parents are not only unsure of what to anticipate as their child develops, but are also uncertain of when, how or how much they are to help their babies reach various milestones, such as talking, grabbing, discerning right from wrong, or even potty-training,” said Paradis, who presented her findings at Pediatric Academic Society meeting in Honolulu.

She and colleagues analyzed parenting know-how based on a national sample of parents representing more than 10,000 9-month-old babies.

These parents completed an 11-question survey designed to see which parents were well prepared and which were not.

The survey asked questions like, “Should a 1-year-old child be able to tell between right from wrong?” and “Should a 1-year-old child be ready to begin toilet-training?”

The correct answer to both is no.

Parents who got four or fewer correct answers were considered to have low parenting knowledge.

VIDEO ANALYSIS

The researchers then compared these surveys with a videotaped analysis of the same families teaching their child a new task, such as playing with blocks.

They also looked at information provided by the parents about how often they engaged their children in enrichment activities, such as reading books, singing songs or telling stories.

They found that 31.2 percent of the parents had a low level of knowledge about what to expect from their child, and this was strongly correlated with lower parental education level and income.

“The fact that almost a third of parents could only answer four out of eleven questions correctly was very surprising to us,” Paradis said in a telephone interview.

Even when the researchers controlled for factors like the mother’s age, education, income and mental state, they still found a significant number of parents with unrealistic expectations about their baby’s development.

And that had a negative impact on the parent-child relationship. “Parents who had less knowledge had less quality interaction with their kids,” Paradis said.

Paradis said one way to address the problem is to urge pediatricians to educate parents during well-baby visits.

“My hope for pediatricians is that we’re able to come up with some novel approaches to educating parents in the office setting,” she said.