If you are planning to embrace parenthood, first stop smoking, said experts ahead of World No Tobacco Day.

World No-Tobacco Day is celebrated every year on May 31 to educate people about the perils associated with tobacco consumption.

"Best time to quit smoking is at least four months before pregnancy, that is, whenever you plan pregnancy," Dr Rajashri Tayshete Bhasale, Consultant Gynecologist, Laparoscopic Surgeon and Obstetrician at Wockhardt Hospitals, Mira Road, told IANS.

"Smoking can interfere with females' normally functioning ovaries and reduces the number of mature eggs that can be fertilised by lowering the egg count," Dr Manju Gupta, Senior Consultant - Obstetrician & Gynaecologist, Motherhood Hospitals, Noida.

According to health experts, exposure to even secondhand or passive smoking can harm biological processes during -- preconception, pregnancy, and post-delivery.

"Even during the nine months of pregnancy, a woman's susceptibility to secondhand smoke's effects might alter, reflecting various pathways of harm as the foetus develops and grows," Dr Gupta told IANS.

"Avoid any contact with direct smoke or smoking in the same room. It is seen that traces of smoke are found for hours after smoking, hence any kind of smoking should be avoided in the house and also house guests should be instructed the same way," Dr Bhasale said.

She explained that nicotine, present in tobacco, is a potent vasoconstrictor thus it can lead to abortion, ectopic pregnancy, Intrauterine growth restriction (IUGR) or birth defects in babies.

Women exposed to smoke "are more likely to develop hypertension in pregnancy and its complications. Studies have shown smoking is associated with birth defects like cleft lip, cleft palate, congenital diaphragmatic hernia, limb reduction defect, gastroschisis, and hypospadias. More over-exposure in later months of pregnancy has shown to cause preterm delivery, low birth weight baby, stillbirth, intrauterine foetal demise or even sudden infant death syndrome," Dr Bhasale told IANS.

Tobacco is a leading cause of preventable morbidity and mortality in the country. Smoking is a growing matter of concern in India. Tobacco consumption impacts all the organs of the body.

Smoking contains tobacco which causes lung cancer, asthma, and chronic obstructive pulmonary disease (COPD), which includes emphysema, and chronic bronchitis.

"Other problems due to tobacco are wheezing, chronic cough, increased mucus, and shortness of breath. Smoking declines lung function. Thus, it is the need of the hour to quit tobacco and lead a healthy life. All forms of tobacco are harmful. Moreover, there is no safe level of exposure to tobacco. It is better to quit it in all forms," Dr Samir Garde, told IANS.