Smoking is dangerous for you and your baby. Many studies show that smoking during pregnancy is a risk factor for a number of complications, including miscarriage, low birthweight, premature births, stillbirth and placental abruption. Women who smoke during pregnancy put their baby at risk of sudden infant death syndrome (SIDS) after birth, attention deficit hyperactivity disorder (ADHD) and poor academic performance in school.

This occurs because cigarettes contain toxins like carbon monoxide and nicotine. These affect the development of the baby's organs such as the brain and lungs, by restricting the supply of oxygen and nutrients to the baby.

Therefore, it's best to stop smoking as soon as you begin planning a pregnancy. If you are already pregnant, you should quit as soon as possible to reduce your baby's exposure to harmful chemicals. Also try to avoid exposure to secondhand smoke, as this has also been found to be harmful to the fetus.

Electronic cigarettes (also known as e-cigarettes or vaping) are becoming increasingly popular but there is currently no data available on their use during pregnancy. Experts advise pregnant women to avoid e-cigarettes because there are no studies available to prove whether they are safe or not.

It's equally as important to avoid alcohol, illicit drugs and other recreational substances such as weed (also known as marijuana or cannabis). Some women perceive that weed may be safe since the use of medical marijuana has been legalized in some parts of the world, but the effects of these substances differ in pregnant women compared to the non-pregnant population. The current evidence available is contradictory and experts advise that until more research is done, pregnant women should not assume that it safe to use weed (or marijuana/cannabis) in any form during pregnancy.