Harder To Conceive
Smoking makes it harder for a woman to get pregnant. Female smokers tend to have lower estrogen levels than non-smokers. This seems to be because the granulosa cells surrounding each ovum are inhibited by cigarette toxins. Lower oestrogen levels may fail to stimulate the release of adequate amount of LH, and this can prevent ovulation from occurring. Even if they do ovulate regularly, nicotine and other cigarette toxins can still reduce the chance of fertilisation by making the ova impenetrable to sperm. In general, women who smoke prior to pregnancy are approximately twice as likely to experience a delay in conception. These effect mean that non-smokers are twice as likely as smokers to become pregnant within a year of trying.
Smoking can also shorten a women’s reproductive life – heavy smokers tend to reach the menopause several years early. As fertility tends to decline sharply in the ten years leading up to the menopause, this could mean that the fertility of a 35-year-old smoker may be equivalent to that of a 40-year-old non-smoker.
A woman who smoke during her pregnancy can starve her unborn baby of the oxygen and essential nutrient he or she needs to grow properly. The baby will have a 30% higher odds of being born prematurely. The nicotine in cigarette smoke constricts the blood vessels in placenta and carbon monoxide, which is poisonous, enters the baby’s bloodstream, replacing some of the valuable oxygen molecules carried by hemoglobin in the red blood cells. Moreover, because the fetus cannot breathe the smoke out, he has to wait for the placenta to clear it. These effects account for the fact that, on average, baby born to smoking mother are usually born too early and have low birth weight (less then 2,500 grams or 5.5 pounds), making it more likely the baby will become sick or die.
Higher Risk Of Miscarriage
Women who smoke during pregnancy are twice as likely to experience premature rupture of membranes, placental abruption, and placenta praevia during pregnancy. To compensate for the reduced oxygen hence blood supply, the placenta tends to over-grow and may become detached from the uterus before the end of a woman’s pregnancy. This is known as placental abruption and is a serious condition which can cause life-threatening bleeding for the mother-to-be and baby.
Placenta preavia (where the placenta implants too low in the uterus and can overlie the cervix) is also more common among women who smoke during their pregnancies. In this position, the placenta can become detached in early labour and can cause heavy bleeding. In such instances, an emergency caesarean section is usually needed.
Sudden Infant Death Syndrome (SIDS)
Smoking during and after pregnancy will increase the risk factors of sudden infant death syndrome (SIDS) by 1.4 to 3.0 times.
Babies born to women who smoke are more likely to have a cleft lip or cleft palate – types of birth defect.
- Source: Centers for Disease Control and Prevention (CDC). (2010c).
- Information on birth defect. Retrived Oct 29, 2016, from www.cdc.gov/birthdefects
- March of Dimes, (2010c)
- Maternity Nursing Care, By Lynna Y. Littleton-Gibbs, Joan Engebretson (2013c)