Smoking can be detrimental to unborn babies. A study in China reveals that paternal smoking increases the risk of babies born with congenital heart defects.

Both maternal and paternal smoking poses health risks for an unborn child. However, the study suggests that secondhand smoke inhaled by pregnant women is even more harmful to babies as compared to mothers smoking during pregnancy. The most common source of this passive smoke — the fathers.

Relationship Between Paternal Smoking And CHD

The compilation involved a huge database of 125 observational studies of 137,574 cases of babies with CHDs and 8.8 million prospective parents.

The research is the first to probe the relationship between paternal smoking and maternal passive smoking and the risk of congenital heart defects in babies. Previous research has focused on women smokers.

Overall results of the research concluded that maternal active smoking, maternal passive smoking as well as paternal smoking increased the risk of CHD in offspring.

"Fathers-to-be should quit smoking," advised Dr. Jiabi Qin of the Department of Epidemiology, Xiangya School of Public Health, Central South University in China.

The risk is also said to be higher among Asians.

Refraining from smoking during preconception to early stages of pregnancy may help prevent CHD in a baby.

Risks Of Parental Smoking

The study emphasized that smoking fathers-to-be increase the risk of babies born with CHDs by 74 percent while passive smoking in women raises the risk to 124 percent.

Dr. Qin said women should stop smoking altogether even before trying to get pregnant. Doing this would ensure that mothers-to-be are smoke-free when they conceive.

It is also significant for pregnant women to keep away from people who are smoking.

"Employers can help by ensuring that workplaces are smokefree," Dr. Qin added.

While the exact mechanisms linking parental smoking and high risk of CHD of offspring were not clearly established, previous studies cited indicate that nicotine induces fetal hypoxia, elevates fetal blood pressure level and reduces blood flow to the placenta. The vasoconstrictor action of nicotine also influences the function of muscle cells and cardiac muscles in the aorta.

According to the Centers for Disease Control and Prevention, tobacco smoking during pregnancy raises the risk of health problems for developing babies, including preterm birth, low birth weight, and birth defects of the mouth and lip.

Low-birth-weight babies are much prone to infections, weakened lungs, breathing difficulties, and long-term health problems in adulthood.

Smoking during pregnancy can also result in miscarriage and premature labor. It can also increase the risk of sudden unexpected infant death or SUID.