There is no amount of alcohol that is safe to drink during any trimester of pregnancy, advises a new report from the American Academy of Pediatrics. And all forms of alcohol — including beer, wine and liquor — pose a similar risk to the developing fetus, according to the report from the nation's largest group of pediatricians.

Although studies suggest that most women cut out alcohol completely when they are expecting, a small percentage of mothers-to-be admit that they continue to consume alcohol, and an even smaller amount say they binge drink, the researchers in the report said.

Women who binge drink when they are not pregnant may be more likely to consume alcohol during pregnancy, the researchers noted in their report published online today (Oct. 19) in the journal Pediatrics.

One of the reasons for releasing the report, titled "Fetal Alcohol Spectrum Disorders," is because somerecent research has been interpreted as suggesting that lower levels of alcohol use might be safe during pregnancy, said Dr. Janet F. Williams, a professor of pediatrics at the University of Texas Health Science Center at San Antonio and one of the report's lead authors. [7 Ways Pregnant Women Affect Babies]

But the pediatricians' group doesn't agree with this research interpretation, and says there's more evidence pointing to alcohol's dangers in pregnancy.

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In fact, there's more than 30 years of research that clearly connects alcohol use during pregnancy with birth defects, Williams said. And as detection methods become increasingly more sensitive, recent studies have revealed the subtle effects of prenatal alcohol exposure, she said.

"Prenatal exposure to alcohol is the leading preventable cause of birth defects and developmental disabilities," Williams said. These birth defects may affect the heart, kidneys or bones, as well as hearing, according to the Centers for Disease Control and Prevention.

Mothers who consume alcohol during pregnancy can put the fetus at risk of developing fetal alcohol spectrum disorders, an umbrella term for a group of conditions that can cause physical, behavioral and learning problems in a child.

Prenatal alcohol exposure

Fetal alcohol spectrum disorders (FASDs) are quite prevalent, yet doctors may not always diagnose them in children who have them, Williams told Live Science. But whenever a child exhibits a developmental delay, learning problems and behavioral difficulties, it's possible that FASD is the root issue, she said.

More attention has been paid to the condition called fetal alcohol syndrome, in which children might have more visible physical characteristics of developmental problems, along with learning and behavioral issues. In addition to growth problems, fetal alcohol syndrome has three common facial features: a thin upper lip, a smooth philtrum, or groove between the nose and upper lips, and a reduced distance between an eye's inner and outer corner.

Although Williams said that FASD is more difficult for pediatricians to detect, recognizing it early can improve a child's long-term outcome.

Prenatal alcohol exposure can produce a wide range of toxic effects on the developing fetus that can alter brain function. This can result in a young child or teen who has mild to severe problems with performance in school, attention, memory, judgment and language skills to name a few.

As a result, women who are expecting a baby or trying to become pregnant should refrain from drinking alcohol altogether because there is no completely safe level of alcohol use during pregnancy, Williams said.

Still, some pregnant women may rationalize their own alcohol use during pregnancy as safe because it is sufficiently low or infrequent, she said. If a pregnancy is unplanned, the best approach is for a woman to stop drinking as soon as she knows she is pregnant, Williams advised.

"No alcohol use during pregnancy guarantees that fetal alcohol spectrum disorders will not occur," Williams said. 

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