‘Light smoking’ before pregnancy can cause major health problems

Even “light smoking” — defined as just one or two cigarettes a day — can be a real drag on pregnancy, causing “major health problems” for the newborn, researchers warn in a new study.

Though smoking during pregnancy is known to raise the risk of preterm delivery, low birth weight, restricted fetal growth and other complications, some 5% of US pregnant women admit to lighting up.

Scientists from China sought to figure out if the timing and intensity of cigarette smoking affect newborns.

They analyzed 12.1 million US births between 2016 and 2019. Mothers reported their cigarette habits three months before pregnancy and during each of the three trimesters.

The researchers found that women who smoked tended to be younger, white, unmarried, obese and poorly educated, with more prior births and infrequent prenatal care.

If a mother smoked just before pregnancy, her newborn’s risk of having more than one major health issue was 27% higher. If she smoked during pregnancy, the risk was 31% to 32% higher.

Health woes included newborn breathing struggles that required a ventilation machine, an admission to intensive care, a seizure or serious neurological troubles.

Smoking one or two cigarettes a day before pregnancy raised the risk of these issues by 16%. The risk was 31% higher if the mother smoked 20 or more cigarettes a day. 

The study findings were published Tuesday in the Journal of Epidemiology & Community Health.

The authors acknowledged that the data didn’t differentiate between those who smoked at any point in the three months before pregnancy and those who smoked throughout that period. Plus, information about secondhand exposure to tobacco smoke wasn’t available.

Still, the researchers say the “data suggest that there is no safe period and no safe level of cigarettes consumed shortly before or during pregnancy.”

Dr. Victor Klein, Northwell Health System director for quality and patient safety, obstetrics and gynecology, recommends wearing a nicotine patch and undergoing behavioral therapy before conceiving to learn coping strategies to avoid smoking or vaping during pregnancy.

He pointed out that smokers often downplay the amount they puff to health care providers and in surveys.

“This is an important study with large numbers of pregnancies,” Klein, who was not involved with the research, told The Post. “One can conclude that smoking even small numbers [of cigarettes] is not safe during pregnancy. Stopping smoking prior to pregnancy is best for the safest pregnancy.”