The placenta (afterbirth) is lifeline between mother and child. When a pregnant woman smokes, the oxygen in her blood is replaced by carbon monoxide. Carbon monoxide is a poisonous gas that deprives the muscles, brain and body tissue of oxygen, which hampers functioning of the child’s heart. If the child has not enough oxygen, he/she will suffer from this phenomenon, which is called oxygen starvation. Hypoxia affects for a long period of time. Instant effect is that the movements of the child inside the womb slow down, and the heart rate accelerates, as the child tries to get more oxygen. Movements of the child slow down to thirty minutes after the mother smoked at least one cigarette. – The placenta provides the baby with nutrients; smoking increases the chances that the baby will be born smaller than expected (a child with low birth weight). Studies show that some women consider underweight of the child as an advantage, however, there is plenty of evidences that speak to the contrary. If the child is smaller in size than it should be at birth, it will be smaller at further development. Children born underweight will likely need the intensive care. The placenta is a barrier / filter for certain substances. Unfortunately, it can not hold all of them, and many of them get inside. Nicotine, carbon monoxide and other chemicals contained in tobacco smoke are passed to the child. Cigarettes contain about four thousand chemicals, of which over thirty are known as carcinogens. German studies have shown traces of nitro amino ketones contained in the nicotine, which is the most powerful substance that causes cancer. It was found in 22 infants out of 31 in mothers who smoked during pregnancy.

Effect of nicotine
Nicotine comes to brain through the blood circulation and then in other parts of the body. Eighty percent of nicotine can be decomposed to cotinine, enzymes contained in the liver. Cotinine may act on the uterus, causing contractions or labor. Many chemicals, including nicotine, can instantly get from the blood circulation of the mother into the blood of the fetus. (That’s why doctors are so concerned about the drugs usage of pregnant women). If you smoke during pregnancy, your child is exposed to approximately the same amount of nicotine that you are. This means that as soon as he or she is born, and will no longer receive intravenous nicotine, a lack of nicotine will occur. Clinical studies have shown that nicotine concentration in the placenta, amniotic fluid and fetal serum were respectively higher than the value of maternal serum measurements at various stages throughout pregnancy. Nicotine alters blood pressure of a smoker, heart rate, and even its metabolism. Nicotine immediately gets into the small blood vessels, causing its narrowing, which reduces blood flow to the uterus, and, accordingly, to the child. Nicotine can delay the production of prostacyclin, a potent vasodilators which prevents accumulation of platelets in the arteries. Studies have shown that nicotine increases uterine vascular resistance and decrease blood flow to the uterus, possibly as a result of catecholamine. Smoking dramatically and chronically reduces blood flow to the uterus, apparently as a result of nicotine. There is evidence that nicotine reduces fetal growth and can lead to an increased risk of sudden premature termination of pregnancy and premature birth. Possible cause of fetal growth retardation is a fetal ischemia (reduced blood flow) and hypoxia (oxygen deficiency), due to the effect of nicotine on the placental circulation. Nicotine coming from cigarettes, or replacement therapy, effects negatively on human health. Studies among female smokers showed that 74 percent would like to quit, but despite these attempts, most women remain dependent on nicotine and have difficulties of overcoming their addiction to this drug. Pregnant women who smoke are often very motivated to quit smoking, especially in the early stages of pregnancy, but many of them continue to smoke. Smoking among mothers is remarkably high 23% and only 3% of women quit smoking by relying only on their own willpower. There is an increased risk when the prospective mother smokes. Risk of miscarriage is higher by 27% among smokers. Mortality during birth (defined as stillbirth or neonatal death within the first week of life) is increased by one third among children of smoking women. The risk of underweight is three times higher. Moreover, the more cigarettes a woman smokes during pregnancy, the greater the probable reduction in birth weight. Recent studies have shown that cigarettes can reduce blood flow to the placenta, which limits the amount of nutrients entering the fetus. There are 35% cases of sudden infant death during sleep, associated with smoking during pregnancy. Smoking mother is associated with increased risk of cancer in children. Infants of smoking parents have the risk of serious respiratory infections than infants of nonsmoking parents. Smoking during pregnancy also increases the risk of asthma in babies. Smoking during pregnancy is associated with behavioral problems and lack of attention. Women who smoked more than one pack of cigarettes a day were significantly more susceptible to have children with behavior problems. Substance abuse is higher among children of women who smoked during pregnancy, as well as a higher risk of bad behavior. Smoking during pregnancy can also affect the physical growth and mental development of children. It was noted that children of smokers are experiencing slower growth compared with nonsmokers, and poor progress in reading and mathematics until the age of sixteen years, and even higher qualifications obtained in twenty-three years. On average, smokers have more complications during pregnancy and childbirth, which may include bleeding during pregnancy, premature separation of placenta and premature rupture of membranes. Some studies have also shown an association between smoking and ectopic pregnancy, and birth defects in children of smoking women. Women often experience nausea, urinary tract infections, thrush, feel bad and often visit hospital. There is also evidence that smoking violates the hormonal balance in women during pregnancy and that this may have consequences on the reproductive organs of their children.