SUNDAY, April 13, 2003 (HealthDayNews) -- Newborn rats exposed to nicotine in the womb have an increased risk of apnea, a condition where breathing simply stops.
That's the claim of a study presented April 12 at the Experimental Biology meeting in San Diego.
University of Arizona researchers exposed developing rat fetuses to nicotine and found that it led to enhanced function of GABAa receptors, an important component of brain cells that control breathing rhythm.
This increased function of GABAa receptors in the baby rats made them more likely to suffer apnea.
The amount of nicotine given to the pregnant mother rats was calculated to produce nicotine blood levels equal to those found in a person who smokes two packs of cigarettes per day. The mother rats were given the nicotine from the fifth day of pregnancy through to the 21st day, when they delivered their pups.
The researchers suggest their findings offer important evidence that exposure to nicotine in the womb increases the functional capacity or density of GABAa receptors on neurons that control breathing.
This evidence in newborn rats may indicate that prenatal nicotine exposure could be a factor in causing human babies to suffer frequent, longer-lasting and possibly fatal apnea episodes.
Sudden Infant Death Syndrome (SIDS) cases occur most often in human babies between the ages of two to four months, while they are sleeping. These deaths are often attributed to apnea or breathing cessation and the failure of the baby to resume breathing.
Previous research has found that babies of mothers who smoke during pregnancy have a five times greater risk of SIDS.
More information
Here's where you can learn more about SIDS.
