New Delhi, Aug 21 (IANS): Even modest smoking of just 1-2 cigarettes per day, either before or during pregnancy is strongly linked to serious health issues for the foetus, warned research.

The research, led by Shandong University researchers in China, reinforces the body of evidence suggesting that women who are or planning to get pregnant should quit smoking to safeguard the health of their unborn child.

Previous research has linked smoking during pregnancy with the increase in the risk of preterm delivery, low birth weight, and restricted growth of the foetus.

However, the possibility that a newborn could be impacted by the mother's timing and intensity of cigarette smoking is less understood.

The researchers note that this is significant since many women think it's acceptable to smoke before getting pregnant, during the first three months of pregnancy, or that mild smoking is probably not detrimental.

For the study, they used national birth certification data from the US from 2016 to 2019 -- a total of 15,379,982 recorded live births.

Smoking was associated with an increased risk of major neonatal health issues, including the need for assisted ventilation, NICU admission, surfactant replacement therapy, suspected sepsis, and seizure or serious neurological problems.

The prevalence of these issues was just under 9.5 per cent. Smoking before pregnancy or during the first, second, or third trimester was associated with higher odds of their newborn experiencing more than one major health issue.

Even light smoking, such as 1-2 cigarettes a day, was associated with a heightened risk of major neonatal health issues, according to the findings published in the Journal of Epidemiology and Community Health.

The study concludes that there is no safe period or level of cigarette smoking shortly before or during pregnancy and emphasises the need to prevent smoking initiation for non-smokers and promote smoking cessation for smokers.