Smoking cigarettes is a common habit that many women get into in their young age and find so hard to get rid of by the time it really matters to avoid it. Continuous studies on smoking and its effects on pregnancy have reported its possible disadvantages on the infant. Orofacial deformations like cleft lip palettes can not only cause embarrassment and poor self-esteem on the children but also add medical costs to resolve it.
In a study done by Dr. Rachel M. Freathy, et.
al. (2009), women may find it hard to quit smoking during pregnancy because of a common genetic variant in the 15q24 nicotinic acetylcholine receptor gene cluster. The study was made by observing the smoking habits of 7,845 pregnant women from South West England. According to the report, 34 percent of the samples with the addictive gene claimed to quit by their last trimester compared to the 47 percent of the women with the non-addictive gene.
Although the project provides the largest sample of women in an observational study related to pregnancy and smoking cessation, the manner of observation was based on self-reports done by the participants which lessens the credibility of the data. Orofacial cleft defects affects an estimated 0.5 to 3 per 1000 births across all races (Krapels, et al., 2006). These defects can be traced to many environmental factors. In a study conducted by Dr. Irina Cech, et al.
(2007) on the cleft births in Harris Country, Texas during the period of 1990 to 1994, the levels of radium and radon in drinking water was revealed to be a possible cause. The weakness of this report is that it has based its reports on extrapolated data obtained from water distribution systems and not specifically the tap water in the samples’ households.A study conducted by Dr Susan Lieff, et al. (1999) claims that maternal smoking does not affect the development of orofacial cleft defects on the infants.
Using data from 3,774 mothers interviewed between 1976 to 1992, the researchers tried to analyze the effects of maternal smoking during the first trimester of pregnancy paying attention to the dose of nicotine. It also included its observations on the dietary and supplemental folate intake of the mothers and their family’s history of clefts. The results showed that there is only a small risk involved for women to be born with children with cleft defects if they smoked during their first trimester of pregnancy. Limitations of the study includes the use of only women from the white race. Factors stemming from racial and genetic relationship to maternal smoking could have been a link to more accurate results.
Another study by Dr. Wyszynski, et al. (2002), calculated data by using the United Natality database of 1997.
The researchers considered the cases of 2,029 nonsyndromic oral clefts and 4,050 of nonmalformed controls based on parental race, child’s gender, county and birth month. These were extracted from 3,093,821 births representing 80 percent of live births all over the country for that year. The results also showed that maternal smoking almost does not exist as a threat to orofacial cleft defects in infants. The limitation of the study includes, however, the fact that one cannot know the exposure of the women to other risk factors that may result to cleft defects based only on natality records.A case-controlled study (Little, et al. 2004), this time in the United Kingdom, also suggests that maternal smoking may not be a huge factor in the development of orofacial cleft defects on the infants. The researchers assessed the mothers and babies of 191 samples through a structured interview based on the mother’s exposure to tobacco smoke. Results showed that there was a positive relationship between maternal smoking during the first trimester to the birth of infants with cleft defects but it was not strong enough to suggest that smoking was a huge influence in the development of orofacial cleft defects.
Limitations of the study include the bias that mothers may not recall well their experiences and may affect the calculations of the data. Smoking during pregnancy has been associated with the problem of having babies with orofacial cleft defects. However, the studies above prove that there is only a small risk involved for the babies to have these defects when their mothers smoke during pregnancy. This does not conclude, of course, that maternal smoking cannot be associated with the risk of having babies with birth defects since many researches are also being done to see its effects on other aspects of infant health.ReferencesCech, I., Burau, K.
D., and Walston, J. (2007). Spatial Distribution of Orofacial Cleft Defect Births in Harris County, Texas, 1990 to 1994, and Historical Evidence for the Presence ofLow-level Radioactivity in Tap Water.
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