According to the study, conducted in the University of Michigan Health System, chronic snorers or moms who snored before and during pregnancy are two thirds more likely to have a baby that's born below the tenth percentile for babies of the same gestational age compared to non-snorers.
Chronic snorers are also more than twice as likely to need an elective C-section, researchers found.
Lead author Louise O'Brien, Ph.D., M.S., associate professor at U-M's Sleep Disorders Center, said that chronic snoring is associated with both smaller babies and C-sections, even after accounting other risk factors.
The study suggests that doctors have a window of opportunity to screen pregnant women for breathing problems during sleep that may put them at risk of poor delivery outcomes, O'Brien explained.
Timing of snoring patterns also made a difference in outcomes, researchers found.
Meanwhile, those who started snoring only during pregnancy had higher risk of both elective and emergency C-sections than women who did not snore.
The study included 1,673 pregnant women, who were recruited from prenatal clinics at U-M between 2007 and 2010, with 35 percent of the women reporting habitual snoring.
The study is published in the scientific journal Sleep.