Maternal cigarette smoking and the associated risk of having a child with orofacial clefts in China: a case-control study

An intercontinental comparison of the influence of smoking on the occurrence of nonsyndromic cleft lip and palate: a meta-analysis and systematic review

BACKGROUND

The influence of smoking on nonsyndromic clefts has been a topic of research for many years. However, few studies have investigated the effect of smoking on causing clefts in different gene pools.

METHODS

A meta-analysis was conducted of case-control studies related to smoking. Keywords such as "clefts," "cleft lip," "cleft palate," "orofacial cleft," and "smoking" were used to search the MEDLINE, Embase, and Cochrane databases.

RESULTS

In total, 51 articles were reviewed. The RevMan software was utilized for the analysis, and the Mantel-Haenszel method was employed to pool the odds ratios (ORs) and 95% confidence intervals. Although the overall OR, a measure of the association between exposure and outcome, was higher for smokers than for non-smokers, this association was significantly stronger in individuals from Asia and South America (1.73), and lowest in Europe (1.31). Among active and passive smokers in Asia, the OR was approximately 0.93, indicating an equivalent impact from both types of smoking.

CONCLUSION

This analysis indirectly suggests that restriction measures targeting both active and passive smoking are crucial in Asia.

3D-printed TCP-HA scaffolds delivering MicroRNA-302a-3p improve bone regeneration in a mouse calvarial model

OBJECTIVE

To demonstrate hydroxyapatite nanoparticles modified with cationic functional molecules. 3-aminopropyltriethoxysilane (HA-NPs-APTES) carrying microRNA-302a-3p (miR) in the 3D-printed tricalcium phosphate/Hydroxyapatite (TCP/HA) scaffold can increase healing of the critical-sized bone defect.

MATERIALS AND METHODS

3D-printed TCP/HA were modified with HA-NPs-APTES by two methods (M1, M2). The dispersion of particles was visualized by fluorescent microscopy. Biocompatibility of the scaffolds was tested by alizarin assay. Delivery of miR to the cells and osteogenic gene expression were evaluated by qPCR. After selecting best method (M2), scaffolds, scaffolds+HA-NPs-APTES with or without miR were implanted in 4 mm mouse calvarium defect (n = 4 per group). After 2,4 and 6 weeks, bone regeneration were evaluated by microCT and histology sections.

RESULTS

Both M1 and M2 scaffolds were biocompatible with cell adhesion on its surface. M2 scaffold showed significant increase of miR, suggesting successful delivery, resulted in downregulation of its target mRNA COUP-TFII, and upregulation of RUNX2 mRNA. Calvarium defect with M2 scaffold also showed significantly higher BV/TV and higher number of filled spaces at all time points. Histomorphometry demonstrated new bone formed at the center of the HA-NPs-APTES-miR scaffold earlier than controls.

CONCLUSION

TCP/HA scaffold modified with HA-NPs-APTES facilitated delivery of miR and enhanced bone regeneration.

Environmental tobacco smoke exposure and non-syndromic orofacial cleft: Systematic review and meta-analysis

INTRODUCTION

Environmental tobacco smoke (ETS) is associated with several congenital anomalies, including non-syndromic orofacial clefts (NSOFCs). This systematic review aimed to update the literature on the association between ETS and NSOFCs.

METHODS

Four databases were searched up to March 2022, and studies that evaluated the association between ETS and NSOFCs were selected. Two authors selected the studies, extracted the data, and evaluated the risk of bias. Comparing the association of maternal exposure to ETS and active parental smoking with NSOFCs allowed for the creation of pooled effect estimates for the included studies.

RESULTS

Twenty-six studies were deemed eligible for this review, of which 14 were reported in a previous systematic review. Twenty five were case-control studies, and one was a cohort study. In total, these studies included 2142 NSOFC cases compared to 118129 controls. All meta-analyses showed an association between ETS and the risk of having a child with NSOFC, based on the cleft phenotype, risk of bias, and year of publication, with a pooled increased odds ratio of 1.80 (95% CI: 1.51-2.15). These studies had a marked heterogeneity, which decreased upon subgrouping based on the recent year of publication and the risk of bias.

CONCLUSIONS

ETS exposure was associated with more than a 1.5-fold increase in the risk of having a child with NSOFC, showing a higher odds ratio than paternal and maternal active smoking.

TRIAL REGISTRATION

The study is registered on the International Prospective Register of Systematic Reviews database # CRD42021272909.

Mothers' knowledge and experience concerning presurgical orthopedic management for infants with cleft lip and palate

OBJECTIVES:

The present study aimed to assess the level of mothers’ knowledge toward cleft lip and palate and their experience concerning presurgical orthopedic management.

MATERIALS AND METHODS:

This was a cross-sectional study where the mothers were invited to complete a self-administered validated and reliable questionnaire. The questionnaire included questions that aimed to assess mother's knowledge related to the most prevalent aspects of cleft lip and palate anomaly itself and additionally, questions associated with presurgical orthopedic treatment as an adjunct therapy. Descriptive statistics were used to define the characteristics of the study variables. Chi-square test was utilized to assess relationships between categorical variables.

RESULTS:

Totally, 145 mothers completed the survey (response rate was 73%). Forty-six (46%) of the mothers provided an incomplete or improper definition of the anomaly and 35 (24%) claimed that they know the cause of the anomaly. The majority of mothers did not identify family history as a risk factor; consanguinity was identified in 29% (n = 42). Of the total, 58 mothers (40%) agreed that dental management of CLP requires teamwork and the majority (n = 126, 87%) recognized the plastic surgeon as the most important specialist. Mothers aged 20-30 years old (n = 42, 53%), and those who are university graduates (n = 38, 48%), as well as employed mothers (n = 52, 66%) have in general a higher degree of knowledge regarding cleft lip and palate (P < 0.001). More than half of the mothers (n = 70, 57%) reported that presurgical orthopedic treatment was useful and needed for their infants.

CONCLUSIONS:

Most of the mothers reported a high level of knowledge about cleft lip and palate and they experienced the usefulness of the orthopedic appliances for their infants. However, there was uncertainty in some parts such as definition, diagnosis, causes, and risk factors for cleft lip and palate. Therefore, understanding the causes of cleft lip and palate, as well as comprehensive education concerning the essential role of the orthopedic appliances to improve cleft lip and palate are crucial for mothers to improve their infants’ quality of life.

Maternal Cigarette Smoking and Cleft Lip and Palate: A Systematic Review and Meta-Analysis

Objectives

A systematic review and meta-analysis to determine the association between active maternal smoking and cleft lip and palate etiology.

Data sources

Medline, Embase, Web of Science and the Cochrane Library from inception to November, 2020.

Study selection

Observational studies of cigarette smoking habits in pregnant women. Outcomes included cleft lip and/or palate, cleft lip  ±  palate and cleft palate only.

Data analysis

Publication bias analyses were performed and the Newcastle Ottawa scales were used to assess study quality. Fixed or random effect models were used in the meta-analysis, dependent on risk of statistical heterogeneity.

Results

Forty-five studies were eligible for inclusion of which 11 were cohort and 34 were case–control studies. Sixteen studies were of sufficient standard for inclusion in the meta-analysis. The summary odds ratio for the association between smoking and cleft lip and/or palate was 1.42 (95%CI 1.27-1.59) with a population attributable fraction of 4% (95%CI 3%-5%). There was limited evidence to show a dose–response effect of smoking.

Conclusions

This review reports a moderate association between maternal smoking and orofacial cleft but the overall quality of the conventional observational studies included was poor. There is a need for high quality and novel research strategies to further define the role of smoking in the etiology of cleft lip and palate.

A Retrospective Cohort Study to Evaluate the Association Between Types of Nonsyndromic Oral Clefts and a Child's Gender and Maternal Age

Aims

To evaluate the association between nonsyndromic cleft lip with or without cleft palate (NSCL±P) anomaly and the affected child's gender and maternal age.

Materials and Methods

Records of 141 newborns received at the orthodontic craniofacial clinic of the Jordanian Royal Rehabilitation Center between 2017 and 2019 were retrospectively analyzed. Two variables were paid attention to: child's gender and maternal age. Five cleft types were considered: unilateral CLP (right; URCLP and left; ULCLP), bilateral CLP (BCLP), isolated cleft palate (CP) and isolated cleft lip (CL). Maternal age was classified into four subgroups: "26-30" years, "31-35" years, "36-40" years, and "above 40" years. Chi-square test and multinomial logistic regression analysis were used to analyze the resultant data.

Results

A significant occurrence of the NSCL±P in females was found compared with males. The different cleft types were found to be significantly associated with the different maternal age groups investigated. The ULCLP was the most prevalent cleft type for affected children among all maternal age groups except the "31-35" group, at which the BCLP exceeded.

Conclusions

The children's gender and the maternal age have a significant impact on defining the developing oral cleft types.

Congenital malformations are associated with secondhand smoke among nonsmoking women: A meta-analysis

BACKGROUND

The association between active maternal smoking and congenital malformations is well established, but little is known about the association between secondhand smoke and congenital malformations. Moreover, studies regarding the association between congenital malformations and secondhand smoke have not yielded consistent results.

METHODS

In July 2018, we searched PubMed, EMBASE, and China Biology Medicine databases for observational studies characterizing the relationship between secondhand smoke and congenital malformations of offspring in nonsmoking women. Two reviewers independently decided on whether a study should be included, did data extraction, and assessed study quality. Pooled risks with 95% confidence intervals were calculated using either the fixed-effects models or random-effects models. Further subgroup analyses and sensitivity analyses were performed to explore the potential source of heterogeneity and to examine the robustness of risk estimates.

RESULTS

Thirty-three studies with a total of 31 944 cases and 32 335 controls were included. Secondhand smoke exposure was associated with an increased risk of congenital malformations (odds ratio = 1.92; 95% confidence interval 1.61-2.30). Secondhand smoke was correlated with significantly increased risk for digestive system (1.17 [1.05-1.32]), nervous system (1.74 [1.33-2.29]), and cardiovascular system (2.10 [1.32-3.35]) malformations and for oral clefts (1.87 [1.47-2.39]).

CONCLUSIONS

Secondhand smoke exposure increases the risk for overall and several organ-system malformations. These findings highlight the necessity of improving community awareness to prevent secondhand smoke exposure during the preconception and conception periods.

Is there an association between maternal smoking and oral clefts?

Data sourcesCochrane, PubMed and Ovid Medline. A search timeline of January 1966 to May 2015 was used and language was restricted to English.Study selectionCase-control and cohort studies relating to oral clefts, with information on maternal active smoking, before and after conception, excluding paternal smoking and exposure to environmental tobacco smoke.Data extraction and synthesisTwo authors extracted data independently. Both Begg's and Egger's funnel plots were used to assess publication bias. Sensitivity analysis was performed to assess impact of the different study types and chi-squared and P values were determined by SPSS software. Studies with missing data were excluded from the meta-analysis.ResultsA statistically significant association was found between maternal active smoking and CL +/- P (odds ratio [OR] 1.368; 95% confidence interval [CI] 1.259-1.486) as well as CP (OR 1.241; 95% CI 1.117-1.378). Half the studies showed positive dose-response effect for each subgroup (test for linear trend, P < .05).ConclusionsWomen who smoke during pregnancy have a moderate risk of having a child with a CL +/- P or CP. A dose-response effect between maternal smoking and clefts was not established.

Associations between maternal periconceptional exposure to secondhand tobacco smoke and major birth defects

BACKGROUND

While associations between secondhand smoke and a few birth defects (namely, oral clefts and neural tube defects) have been noted in the scientific literature, to our knowledge, there is no single or comprehensive source of population-based information on its associations with a range of birth defects among nonsmoking mothers.

OBJECTIVE

We utilized data from the National Birth Defects Prevention Study, a large population-based multisite case-control study, to examine associations between maternal reports of periconceptional exposure to secondhand smoke in the household or workplace/school and major birth defects.

STUDY DESIGN

The multisite National Birth Defects Prevention Study is the largest case-control study of birth defects to date in the United States. We selected cases from birth defect groups having >100 total cases, as well as all nonmalformed controls (10,200), from delivery years 1997 through 2009; 44 birth defects were examined. After excluding cases and controls from multiple births and whose mothers reported active smoking or pregestational diabetes, we analyzed data on periconceptional secondhand smoke exposure-encompassing the period 1 month prior to conception through the first trimester. For the birth defect craniosynostosis, we additionally examined the effect of exposure in the second and third trimesters as well due to the potential sensitivity to teratogens for this defect throughout pregnancy. Covariates included in all final models of birth defects with ≥5 exposed mothers were study site, previous live births, time between estimated date of delivery and interview date, maternal age at estimated date of delivery, race/ethnicity, education, body mass index, nativity, household income divided by number of people supported by this income, periconceptional alcohol consumption, and folic acid supplementation. For each birth defect examined, we used logistic regression analyses to estimate both crude and adjusted odds ratios and 95% confidence intervals for both isolated and total case groups for various sources of exposure (household only; workplace/school only; household and workplace/school; household or workplace/school).

RESULTS

The prevalence of secondhand smoke exposure only across all sources ranged from 12.9-27.8% for cases and 14.5-15.8% for controls. The adjusted odds ratios for any vs no secondhand smoke exposure in the household or workplace/school and isolated birth defects were significantly elevated for neural tube defects (anencephaly: adjusted odds ratio, 1.66; 95% confidence interval, 1.22-2.25; and spina bifida: adjusted odds ratio, 1.49; 95% confidence interval, 1.20-1.86); orofacial clefts (cleft lip without cleft palate: adjusted odds ratio, 1.41; 95% confidence interval, 1.10-1.81; cleft lip with or without cleft palate: adjusted odds ratio, 1.24; 95% confidence interval, 1.05-1.46; cleft palate alone: adjusted odds ratio, 1.31; 95% confidence interval, 1.06-1.63); bilateral renal agenesis (adjusted odds ratio, 1.99; 95% confidence interval, 1.05-3.75); amniotic band syndrome-limb body wall complex (adjusted odds ratio, 1.66; 95% confidence interval, 1.10-2.51); and atrial septal defects, secundum (adjusted odds ratio, 1.37; 95% confidence interval, 1.09-1.72). There were no significant inverse associations observed.

CONCLUSION

Additional studies replicating the findings are needed to better understand the moderate positive associations observed between periconceptional secondhand smoke and several birth defects in this analysis. Increased odds ratios resulting from chance (eg, multiple comparisons) or recall bias cannot be ruled out.

Environmental factors related to the occurrence of oral clefts in a Brazilian subpopulation

Background:

A cross-sectional study was conducted at the Craniofacial Rehabilitation Center in the General Hospital of the University of Cuiabá, Cuiabá city, Mato Grosso, Brazil.

Materials and Methods:

Poisson regression model was used to analyze the relationship between antenatal factors and the occurrence of oral clefts in 116 patients.

Results:

Oral clefts were more common in males (64.66%) and White race (46.02%). The mean age of the children was 21.91 months. The most common type of cleft was cleft lip and palate (CLP, 55.17%). Maternal and paternal smoking in the first trimester of pregnancy and parity were significantly associated with the occurrence of CLP. Parent's age, educational level, and occupation did not interfere in the occurrence of oral clefts. There was also no significant association between maternal illness, medication use, alcohol consumption, and maternal exposure to chemicals in the first trimester of pregnancy and the occurrence of clefts in this population.

Conclusion:

The analysis of the environmental factors present during the pregnancy of children with oral clefts revealed a significant association between parity (second onward), maternal smoking, and paternal smoking and the occurrence of CL and/or palate in this population.

Environmental Risk Factors in the Etiology of Nonsyndromic Orofacial Clefts in the Western Region of Saudi Arabia

OBJECTIVES

Nonsyndromic orofacial cleft (NSOFC) etiology is multifactorial and heterogeneous. This study aimed to identify environmental risk factors related to NSOFC in the Western Region of Saudi Arabia.

METHODS

A case-control study carried out in seven hospitals in two main cities (Jeddah and Maddina) over 2 years on parents of 112 infants with NSOFC (infants were also examined) and 138 infant controls, matched for age (<18 months), gender, and location, completed a questionnaire on 3-month pregestation and first trimester events.

RESULTS

There was significantly increased NSOFC risk with twin pregnancies (P = .01, odds ratio [OR] = 9.5, 95% confidence interval [CI]: 1.15 to 78.4), maternal antibiotic use (P = .021, OR = 2.71, 95% CI: 1.11 to 6.62), antiemetic medication (P = .005, OR = 2.85, 95% CI: 1.3 to 6), severe morning sickness (P = .006, OR = 3.6, 95% CI: 1.34 to 9.65), illness (P = .009, OR = 2.19, 95% CI: 1.17 to 4.08), common cold/flu (P = .003, OR = 3.32, 95% CI: 1.48 to 7.58), Jorak smoking (P = .004, OR = 14.07, 95% CI: 1.55 to 128.1), and passive smoking (P = .05, OR = 2.05, 95% CI: 1.05 to 4.01). Reduced NSOFC risk was found with calcium supplementation (P = .02, OR = 0.32, 95% CI: 0.11 to 0.88), incense use (P = .03, OR = 0.58, 95% CI: 0.34 to 0.98), and maternal drinking water, with Zamzam water (which contains a high concentration of minerals) showing a significant protective effect compared with tap water (P = .01, 95% CI: 0.06 to 0.6) and bottled water (P = .02, 95% CI: 0.03 to 0.57).

CONCLUSION

Twin births, maternal antibiotic use, antiemetic medication, severe morning sickness, common cold/flu, Jorak smoking, and passive smoking were associated with infants born with NSOFC. Calcium supplementation, incense use, and Zamzam water reduced the risk of NSOFC, raising the possibility of community preventive programs.

Windows of Sensitivity to Toxic Chemicals in the Development of Cleft Palates

Cleft lip and cleft palate are among the most common birth defects worldwide. There is a genetic component to the development of these malformations, as well as evidence that environmental exposures and prescription drug use may exacerbate or even produce these manifestations. Thus, it is important to understand the underlying mechanisms and when these exposures affect development of the growing fetus. The purpose of this investigation was to critically review the available literature related to orofacial cleft formation following chemical exposure and identify specific time frames for windows of sensitivity. Further, an aim was to evaluate the potential for predicting effects in humans based on animal studies. Evidence indicates that chemical causes of cleft palate development are due to dose and timing of exposure, susceptibility of the species (i.e., the genetic makeup), and mechanism of action. Several studies demonstrated that dose is a crucial factor; however, some investigators argued that even more important than dose was timing of exposure. Data show that the window of sensitivity to environmental teratogens in the development of cleft palates is quite narrow and follows closely the window of palatogenesis in the fetus of any given species.

Passive smoking in the etiology of non-syndromic orofacial clefts: a systematic review and meta-analysis

BACKGROUND

Studies have found a consistent positive association between maternal smoking and non-syndromic orofacial clefts (NSOFC). However, no comprehensive assessment of the association between NSOFC and passive smoking has been undertaken. This systematic review and meta-analysis explores the relationship between maternal passive smoking and NSOFC, and compares the associations between passive and active smoking.

METHODS AND FINDINGS

Search strategy, inclusion / exclusion criteria, and data extraction from studies reporting maternal passive smoking and NSOFC was implemented without language restrictions. Risks of bias in the identified studies were assessed and this information was used in sensitivity analyses to explain heterogeneity. Meta-analysis and meta-regression of the extracted data were performed. Egger's test was used to test for small study effects. Fourteen eligible articles were identified. Maternal passive smoking exposure was associated with a twofold increase in risk of NSOFC (odds ratio: 2.11, 95% confidence interval: 1.54-2.89); this was apparent for both cleft lip with and without palate (OR: 2.05, 95% CI: 1.27-3.3) and cleft palate (OR: 2.11, 95% CI: 1.23-3.62). There was substantial heterogeneity between studies. In the studies that provided data enabling crude and adjusted odd ratios to be compared, adjustment for potential confounders attenuated the magnitude of association to about a 1.5-fold increase in risk.

CONCLUSION

Overall, maternal passive smoking exposure results in a 1.5 fold increase in risk of NSOFC, similar to the magnitude of risk reported for active smoking, but there is marked heterogeneity between studies. This heterogeneity is not explained by differences in the distribution of cleft types, adjustment for covariates, broad geographic region, or study bias/quality. This thorough meta-analysis provides further evidence to minimize exposure to environmental tobacco smoke in policy making fora and in health promotion initiatives.

A case-control study of environmental exposures for nonsyndromic cleft of the lip and/or palate in eastern Guangdong, China

OBJECTIVE

To study the relationship between environmental factors and nonsyndromic cleft of the lip and/or palate (NSCLP) in eastern Guangdong for the prevention of NSCLP.

METHODS

A 1:1 retrospective case-control study was carried out. Data from 479 children with NSCLP who accepted comprehensive care in our center were recruited as cases from April 2010 to April 2013. An equal number of controls were recruited from pediatrics during the same period. Then we conducted face-to-face interviews with both parents using a structural questionnaire to identify the relationship between NSCLP and environmental risk factors.

RESULTS

Univariate Chi-square analysis identified 23 factors (P<0.05) as being significantly related to NSCLP. Stepwise multiple logistic regression analyses demonstrated that there were 16 factors significantly associated with this disease. Being male (OR=0.609), parental childbearing age of 25-29 years (ORfather=0.633; ORmother=0.469), higher parental education level (high school or greater) and folic acid supplementation (OR=0.360) were protective factors against NSCLP. However, positive family history of NSCLP (OR=54.132), positive maternal abortion history (OR=3.698), high or low parental age at time of childbirth, poor maternal education level (primary school) (OR=2.258), maternal common cold during pregnancy (OR=1.464), and drug use during pregnancy (OR=3.364) were significant risk factors for NSCLP.

CONCLUSION

The findings are beneficial for researchers to understand the etiology of NSCLP and to lay a solid foundation for the prevention of NSCLP in eastern Guangdong through educational programs to teach parents about the benefits of folic acid supplementation, adequate parental age at childbirth (25-29 years), higher parental education level (high school or higher), and the dangers of common cold and drug use during the first trimester of pregnancy, positive family history and maternal abortion history.

Self-reported maternal cigarette smoke exposure during the periconceptional period and the risk for omphalocoele

BACKGROUND

We investigated whether maternal exposure to cigarette smoke was associated with omphalocoele and whether periconceptional folic acid modified the association.

METHODS

 : We analysed data from the National Birth Defects Prevention Study on omphalocoele case (n = 301) and control (n = 8135) mothers for infants born from 1997 through 2007. Mothers who reported active smoking or exposure to second-hand smoke during the periconceptional period (1 month before conception to 3 months after) were considered exposed. Those who reported use of folic acid supplements during the same period were considered supplement users. Odds ratios and 95% confidence intervals were estimated using multivariable logistic regression adjusted for alcohol use, preconception body mass index, and race/ethnicity.

RESULTS

One hundred fifteen (38.2%) case and 2592 (31.9%) control mothers reported exposure to cigarette smoke during the periconceptional period. Adjusted odds ratios [95% confidence intervals] were 1.19 [0.94, 1.53] for any smoke exposure, 0.87 [0.54, 1.40] for active smoking, 1.38 [1.00, 1.90] for second-hand smoke exposure, and 1.16 [0.80, 1.67] for both exposures combined. No dose-response relationship was observed. Folic acid-containing supplements did not reduce the risk for omphalocoele among women with active or second-hand smoke exposure.

CONCLUSIONS

Self-reported active maternal smoking, with or without exposure to second-hand smoke, during the periconceptional period was not associated with omphalocoele. In contrast, there was a possible association with periconceptional exposure to second-hand smoke.

The Impact of Paternal and Maternal Smoking on Semen Quality of Adolescent Men

Background

Maternal smoking during pregnancy has been reported to negatively impact sperm counts of the sons. Sufficient data on the effect of paternal smoking is lacking.

Objectives

We wished to elucidate the impact of maternal and paternal smoking during pregnancy and current own smoking on reproductive function of the male offspring.

Methods

Semen parameters including sperm DNA integrity were analyzed in 295 adolescents from the general population close to Malmö, Sweden, recruited for the study during 2008–2010. Information on maternal smoking was obtained from the Swedish Medical Birth Register, and regarding own and paternal smoking from questionnaires. The impacts of maternal, paternal and own smoking were evaluated in a multivariate regression model and by use of models including interaction terms. Totally, three exposures and five outcomes were evaluated.

Results

In maternally unexposed men, paternal smoking was associated with 46% lower total sperm count (95%CI: 21%, 64%) in maternally unexposed men. Both paternal and maternal smoking were associated with a lower sperm concentration (mean differences: 35%; 95%CI: 8.1%, 55% and 36%; 95%CI: 3.9%, 57%, respectively) if the other parent was a non-smoker. No statistically significant impact of own smoking on semen parameters was seen.

Conclusions

Prenatal both maternal and paternal smoking were separately associated with some decrease in sperm count in men of whom the other parent was not reported to smoke.

Orofacial clefts and risk factors in tehran, iran: a case control study

BACKGROUND

Non-syndromic cleft lip with or without cleft palate (CL/P) or cleft palate only (CPO) are orofacial clefts with multifactorial etiology. These include environmental factors and heterogeneous genetic background. Therefore, studies on different and homogenous populations can be useful in detecting related factors. The aim of the present study was to evaluate the risk factors in patients with non-syndromic cleft in Tehran, Iran.

METHODS

Data from 300 patients and 300 controls were collected between 2005 and 2010. Binary logistic regression analyses were used to calculate relative risk by odds ratio (OR) and %95 confidence interval.

RESULTS

Low maternal age (OR=1.06, 95% CI, 1.011-1.113), low socioeconomic status (OR=0.23, 95% CI, 0.007-0.074), maternal systemic disease (OR=0.364; 95% CI, 0.152-0.873) and passive smoking (OR=0.613, 95% CI, 0.430-0.874) increased the risk for CL/P and CPO. There was a significant difference in iron and folic acid use during pregnancy when the case and control groups were compared.

CONCLUSION

In assessing for orofacial cleft risk, we should consider lack of folic acid supplementation use, maternal age and systemic diseases and passive smoking as risk factors.