Effects Of Smoking While Pregnant
Smoking while pregnant can have a detrimental effect on the pregnancy and the newborn. To begin with, smoking (even passive smoking!) can come in the way of conception. In newborns, maternal smoking can result in birth defects, low birth weight, asthma, problems with the renal system. It may even result in the sudden death of the infants, also called cot death.
If you are a smoker trying to get pregnant, you would be doing yourself and your baby a big favor by kicking the butt right away. Want to know why? Statistics show over 1,000 babies in the US die each year because their mothers smoked while pregnant. A staggering 12-20 percent of pregnant women smoke in the US. Passive smoking, too, contributes generously to the number of babies affected by smoking.
The reason is simple. Babies in the womb eat what you eat; they inhale what you inhale. When you smoke cigarettes, you inhale poisons such as nicotine, lead, arsenic, and carbon monoxide which get into placenta that provides the life support for your baby. Result? The adverse effect of maternal smoking leads to difficulty in conception, low birth weight, birth defects and sometimes even sudden death in babies. According to American Lung Association, smoking during pregnancy is estimated to account for 20 to 30 percent of low birth weight babies, up to 14 percent of preterm deliveries, and about 10 percent of all infant deaths.1
Some studies show smoking can affect the renal system of the babies and also result in asthma. Here is a detailed look at the effects of smoking while pregnant:
Effects Of Smoking While Pregnant
1. Difficulty In Conceiving
Did you know that in most cases, menopause occurs one to four years earlier in women who smoke when compared with nonsmokers? That is because the rate at which the eggs are lost increases with chemicals like nicotine, cyanide, and carbon monoxide in cigarette reaching the womb. And eggs, if lost once cannot be regenerated or replaced. Smoking of the male partner, too, pauses problems in conceiving as the sperm quality and the motility as well as the count decrease in male smokers. Smoking also results in abnormally shaped sperms and decreases its ability to fertilize eggs. These are some of the reasons why women smokers find it difficult to conceive than others; the infertility rates in both male and female smokers are about twice the rate of infertility found in nonsmokers. Studies have found that even IVF may not be able to help smokers conceive. And even if they do conceive, they have more chances of having a chromosomally unhealthy pregnancy (such as a pregnancy affected by Down syndrome).2
2. Tobacco Affects Placenta
Studies have shown that chronic exposure to tobacco in early pregnancy can affect the health of the placenta because of the reduced blood flow to it. Result? Adverse pregnancy outcomes, mostly!3
Placenta previa: Placenta previa is a condition that occurs during pregnancy where the placenta is abnormally placed and covers the cervix partially or totally. This can lead to complicated pregnancies. Studies have shown that maternal smoking doubled the chances of placenta previa.4
3. Chances Of Ectopic Pregnancy
Another pregnancy-related complication often seen with maternal smoking is ectopic pregnancy where the fetus develops outside the uterus, mostly in the fallopian tube. Epidemiological studies have shown increased chances of ectopic pregnancy among smokers. Smoking could alter tubal epithelial cell turnover and change it structurally and functionally contributing to ectopic pregnancies.5
4. Miscarriage/Early Pregnancy
Active smoking among pregnant women was found to be associated with increased risk of miscarriage or abortions with the risk increasing by 1 percent for every cigarette smoked. Even second-hand smoking contributed to the risk of miscarriage by 11 percent.6 Similarly, smoking also has a dose-related impact on the risk of preterm birth.7 Studies have shown smoking also increased the risk of preterm premature rupture of membranes, and late pregnancy bleedings.8
5. Babies Born With Low Birth Weight
In a study done to understand the effect of smoking on the birth weight of the babies and maternal weight gain showed that while the maternal weight gain did not vary much between smokers and nonsmokers, smoking contributed significantly to the reduced birth weight of the babies, some of them as low as 2500 grams.9 There is no debating that smoking increases the chances of low birth weight among newborns but in a Japanese study on 92641 participants, it was also found that the strength of the association between maternal smoking and low birth weight increased with maternal age.10 The older the mother who smokes, the more are her chances of delivering a baby that weighs less.
6. Increased Chances Of Birth Defects
Maternal smoking is associated with a plethora of birth defects from cardiovascular/heart defects, musculoskeletal defects and limb reduction defects to chances of missing or extra digits, clubfoot, facial defects, eye defects, orofacial clefts, gastrointestinal defects, anal atresia, undescended testes, and more.11
7. Sudden Infant Death Syndrome
Sudden infant death syndrome (SIDS) continues to be the most prevalent cause of postneonatal infant mortality in the US with prenatal maternal tobacco use identified as a risk factor.12 There is a two-fold risk of SIDS among infants born to mothers who smoke.13
8. Smoking Affects Infant Renal System
Proteinuria is a condition where protein spills into the urine. It could be benign but when it is sustained and present in the urine in increasingly significant amounts, it is an indication of an underlying disease or a damage of the kidney. A Japanese study that set out to explore the relationship between maternal smoking and proteinuria in infants and small children found maternal smoking during pregnancy as one of the risk factors of childhood proteinuria.14
9. Childhood Asthma
It’s a known fact that maternal smoking has an effect on childhood asthma. This was further bolstered by a study done by a research team which spanned 16 institutes and centers in the continental United States, Puerto Rico and Mexico that tried to assess at what stage of the child’s growth was maternal smoking most impactful. Not surprisingly, it was found that maternal smoking during pregnancy had the most impact on childhood asthma.15
Does Second Hand Smoking Affect Pregnancy?
While maternal smoking is dangerous to the health of the babies, second-hand smoke, and even third-hand smoke are found to be detrimental to the health and development of the babies. Babies have small lungs and toxins from second or third-hand smoking build up over time affecting the child’s health adversely.16 Second-hand smoke can reduce the baby’s birth weight and increase the risk of cot death or SIDS. Babies whose parents smoke are more likely to get lung diseases like bronchitis and pneumonia during their first year.17
The sooner you stop smoking the better it is for the baby. Consider these while smoking next time:
- By stopping smoking, you are preventing harmful gases and toxins from entering your body and causing damage to the baby.
- Pregnancy complications will be reduced.
- Reduced risk of stillbirth, preterm birth, and cot death.
- Better birth weight in babies.
References [ + ]
|1.||↑||Smoking During Pregnancy. APA.|
|2.||↑||Smoking And Infertility. American Society For Reproductive Medicine.|
|3.||↑||Zdravkovic, T., O. Genbacev, M. T. McMaster, and S. J. Fisher. “The adverse effects of maternal smoking on the human placenta: a review.” Placenta 26 (2005): S81-S86.|
|4.||↑||Kramer, Michael D., Victoria Taylor, Durlin E. Hickok, Janet R. Daling, Thomas L. Vanghan, and Kathryn A. Hollenbach. “Maternal smoking and placenta previa.” Epidemiology 2, no. 3 (1991): 221-223.|
|5.||↑||Horne, Andrew W., Jeremy K. Brown, Junko Nio-Kobayashi, Hazirah BZ Abidin, Zety EHA Adin, Lyndsey Boswell, Stewart Burgess, Kai-Fai Lee, and W. Colin Duncan. “The association between smoking and ectopic pregnancy: why nicotine is BAD for your fallopian tube.” PLoS One 9, no. 2 (2014): e89400.|
|6.||↑||Pineles, Beth L., Edward Park, and Jonathan M. Samet. “Systematic review and meta-analysis of miscarriage and maternal exposure to tobacco smoke during pregnancy.” American journal of epidemiology 179, no. 7 (2014): 807-823.|
|7.||↑||Kyrklund-Blomberg, Nina B., and Sven Cnattingius. “Preterm birth and maternal smoking: risks related to gestational age and onset of delivery.” American journal of obstetrics and gynecology 179, no. 4 (1998): 1051-1055.|
|8.||↑||Kyrklund‐Blomberg, Nina B., Fredrik Granath, and Sven Cnattingius. “Maternal smoking and causes of very preterm birth.” Acta obstetricia et gynecologica Scandinavica 84, no. 6 (2005): 572-577.|
|9.||↑||Meyer, Mary B. “How does maternal smoking affect birth weight and maternal weight gain?: Evidence from the Ontario perinatal mortality study.” American journal of obstetrics and gynecology 131, no. 8 (1978): 888-893.|
|10.||↑||Zheng, Wei, Kohta Suzuki, Taichiro Tanaka, Moriyasu Kohama, Zentaro Yamagata, and Okinawa Child Health Study Group. “Association between Maternal Smoking during Pregnancy and Low Birthweight: Effects by Maternal Age.” PloS one 11, no. 1 (2016): e0146241.|
|11.||↑||Hackshaw, Allan, Charles Rodeck, and Sadie Boniface. “Maternal smoking in pregnancy and birth defects: a systematic review based on 173 687 malformed cases and 11.7 million controls.” Human reproduction update 17, no. 5 (2011): 589-604.|
|12.||↑||Pollack, Harold A. “Sudden infant death syndrome, maternal smoking during pregnancy, and the cost-effectiveness of smoking cessation intervention.” American Journal of Public Health 91, no. 3 (2001): 432.|
|13.||↑||Anderson, Mark E., Daniel C. Johnson, and Holly A. Batal. “Sudden Infant Death Syndrome and prenatal maternal smoking: rising attributed risk in the Back to Sleep era.” BMC medicine 3, no. 1 (2005): 4.|
|14.||↑||Shinzawa, Maki, Shiro Tanaka, Hironobu Tokumasu, Daisuke Takada, Tatsuo Tsukamoto, Motoko Yanagita, and Koji Kawakami. “Maternal Smoking during Pregnancy, Household Smoking after the Child’s Birth, and Childhood Proteinuria at Age 3 Years.” Clinical Journal of the American Society of Nephrology (2016): CJN-05980616.|
|15.||↑||Smoking During Pregnancy Linked To Persistent Asthma In Childhood. UCSF.|
|16.||↑||Smoking During Pregnancy. AAP.|
|17.||↑||Stop Smoking In Pregnancy. NHS.|