Consequences of smoking on pregnancy carrying

Consequences of smoking on pregnancy carrying

1. increased risk of ectopic pregnancy

Smoking increases the risk of ectopic pregnancy in a Dose - effect. Nicotine has a direct toxic action on tubal mobility. If smoking is stopped one month before conception, the risk is again equal to that of the general population.

<10 cigarettes / day relative risk (RR) is 1, 5 times greater
> 20 cigarettes / day x 3 RR
> 30 cigarettes / day x 5 RR
2. increased risk of miscarriage
Consequences of smoking on pregnancy carrying
The relative risk of miscarriage in women smokers is 1, 5 to 3, and is dose-dependent. Thus, women who smoke more than 20 cigarettes / day, the risk is 20% compared to 10% for nonsmokers and may reach 35% for consumption of 35 cigarettes / day.
The risk of miscarriage increases in exposure to passive smoking (at least one hour per day).
Consequences of smoking on pregnancy carrying
3. increased risk of uterine

The risk of uterine bleeding (abnormal bleeding) in the third trimester of pregnancy, smoking is also related to dose-dependent. Retroplacentar doubles the risk of hematoma and the placenta praevia is 2-3 times higher in women who smoke during pregnancy.

4. increased risk of preterm birth

Risk does not lead to pregnancy to term is 2 times higher in smokers woman. This risk is dose dependent (consumption <20 cigarettes a day increases the risk of premature birth by 20% and consumption of> 20 cigarettes per day increases the risk by 50%). Moreover, the risk of prematurity related to smoking increases with maternal age.
Consequences of smoking on pregnancy carrying
It should be noted that this increased risk disappears if women quit smoking before conception.
Consequences of smoking on pregnancy carrying
In addition to increased frequency of obstetric complications that may be at the origin of prematurity (placenta praevia or hematoma retroplacentar), there are specific mechanisms.
- Increased risk of fetal death in utero
11% of cases of fetal death in utero can be attributed to tobacco use.
Increased risk of fetal death in utero is explained by intrauterine growth retardation, occurrence of hematoma retroplacentar or placenta praevia.