Contents
The number of pregnant women smoking has decreased slightly over the past 10 years, but about 15% of pregnant women continue to smoke constantly or periodically.
Tobacco smoke contains hundreds of toxic components, some of which may affect pregnancy outcomes.
It is well known that nicotine affects blood circulation and reduces the intensity of blood circulation in the mother-fetus system. Other components of tobacco smoke, cadmium and lead, are found in the follicular fluid and placental tissue of smokers. Lead is a known neurotoxin; and some polycyclic aromatic hydrocarbons have mutagenic activity.
Decreased fertility
It has been proven that the ability to conceive is reduced in 30% of women who smoke. If a man smokes, this can lead to a decrease in the quality of sperm; there is no effect on the efficiency of conception in cases where the woman in the couple is a non-smoker.
Disorders of placental development
The risk of deviations in the process of placental development depends on the duration of smoking; on average, deviations occur 1,5 times more often than in non-smoking women.
The mechanisms of disturbances in the development of the placenta have not been sufficiently studied. It is believed that prolonged spasm of the uterine vessels caused by smoking and decreased blood flow in the developing placenta play a role. Reduced placental blood flow can lead to intrauterine fetal growth retardation.
Of all cases of placental development disorders, 10% are caused by smoking. They can be prevented if a woman stops smoking.
intrauterine growth retardation
Intrauterine growth retardation (IUGR) is the most obvious and well-known outcome of pregnancy in a smoking mother.
Smoking during pregnancy on average reduces the weight of a newborn by 200 g; weight loss directly depends on the number of cigarettes smoked.
The risk of having a baby whose weight is less than 2,5 kg is increased by 2 times and also depends on the number of cigarettes smoked per day.
This risk is especially increased among older women who smoke. If a woman stops smoking in the early stages of pregnancy, this prevents risks.
Premature birth
If cases of impaired placental development caused by smoking are excluded, the risk of premature birth in other smoking mothers will be increased by 30%.
The likelihood of this outcome increases as smoking intensity increases. For example, the risk of premature rupture of water at 33 weeks is doubled in a woman who smokes about 20 cigarettes per day.
It is believed that 5% of all preterm births are caused by smoking during pregnancy. They can be prevented if the woman gives up the habit.
Birth defects
The risk of developing cleft lip and hard palate in infants of smoking mothers is increased by an average of 2 times. There is no evidence of an increased risk of developing other abnormalities due to smoking during pregnancy.
In conclusion, we can summarize the above.
Smoking during pregnancy leads to many abnormalities in fetal development and adverse pregnancy outcomes. The most common deviations are:
- intrauterine growth retardation,
- disturbances in the structure of the placenta,
- increased risk of perinatal mortality
- morbidity of the newborn.
Smoking remains the main behavioral risk factor during pregnancy.
To prevent pathologies of fetal development during pregnancy. We recommend regular examinations and screenings by experienced obstetricians and gynecologists.