Birth Prevalence Of Cleft Palate Research Articles

The Epidemiology of Cleft Lip and Palate in Canada, 1998 to 2007.

To examine the birth prevalence, gender distribution, and pattern of surgical intervention for clefts in Canada (1998 to 2007). Also to highlight the difficulties associated with studying the epidemiology of clefts using the current data collection mechanisms. Epidemiologic data acquired from the Canadian Institute for Health Information. Population-based study in Canada 1998 to 2007. All live births with an International Classification of Diseases (9th or 10th revision) diagnostic code for cleft palate or for cleft lip with or without cleft palate or with a surgical intervention code for repair of cleft lip or cleft palate. Birth prevalence, gender distribution, and pattern of surgical intervention. There were 3,015,325 live births in Canada (1998 to 2007). The mean birth prevalence was 0.82 per 1000 live births for cleft lip with or without cleft palate and 0.58 per 1000 live births for cleft palate. The birth prevalence of cleft lip with or without cleft palate was significantly higher in boys, with a stable boy to girl ratio of 1.75:1. Cleft palate was significantly greater in girls; however, the boy to girl ratio decreased from 0.97:1 in 1998 to 0.59:1 in 2007. The median age of repair in Canada from 1998 to 2007 was 4.7 months for cleft lip and 11.6 months for cleft palate. Thirty percent of patients underwent cleft palate repair after age 1. The birth prevalence of cleft palate and cleft lip with or without cleft palate is stable in Canada. An increasing birth prevalence of cleft palate in girls is suggested. The timing of surgical intervention is consistent with current standards. The challenges associated with collecting these data in Canada are discussed.

Epidemiology of Orofacial clefts in Africa: Methodological challenges in ascertainment.

To carry out a systematic review of the birth prevalence of cleft lip with or without cleft palate (CLP) and cleft palate (CP) in Africa based on available published data. Using the Cochrane search strategy and the following keywords words "cleft palate", "prevalence", "incidence", "cleft lip" and "Africa" to screen Ovid Medline {1966 to March 2007), Cinahl {1982-March 2007}, Pub Med, Scopus, and Web-Google. All identified published, prospective and retrospective studies on the birth prevalence of CLP and CP in Africa were included. The dates, location, sources, number of births (live births, still births, number of cleft cases, prevalence rates, sex ratio, cleft types, and clefts with associated anomalies were extracted. Ascertainment of cases was through the hospitals. Overall there were 57 CL/P, 56 CL and 36 CP reported from all the studies. From seven studies combined, 21 males and 20 females had CL, 10 males and 22 females with CP and 26 males and 24 females with CL/P. There were 3 cases with CL/P, 2 with CP and 2 with CL from the three studies that reported clefts with associated anomalies. For an improved ascertainment of cleft cases, there is a need to set up a birth defects surveillance system in the form of a national birth registry. Future studies should then aim to include the entire population in geographically defined regions. Reliable data on incidence is an essential pre-requisite for studies into aetiology and prevention.

Re: "Risk of Oral Clefts in Relation to Prepregnancy Weight Change and Interpregnancy Interval"

In an earlier issue of this Journal, Villamor et al. (1) reported a strong, positive, linear association between interpregnancy interval and birth prevalence of cleft palate. We were surprised to see a linear increase in risk instead of a J-shaped association. Reported risks of adverse birth outcome typically peak at both ends of the interpregnancy interval spectrum, and lowest risks are found mostly for intervals between 12 and 23 months (2). Although the causes of these excess risks are still uncertain and probably different for short and long intervals (3), we have hypothesized that the increased risks associated with short interpregnancy intervals are (at least partly) attributable to maternal depletion of micronutrients, particularly folate (4). Pregnancy places a burden on maternal micronutrient reserves and, if a new conception occurs before these reserves are sufficiently restored, growth and development of the conceptus may be compromised. Pregnancies accomplished shortly after the preceding delivery, in addition, are more likely than others to be unintended (5), which decreases the probability that periconceptional folic acid (or multivitamin) supplements were used. As Villamor et al. note, the risk of orofacial clefts has been found to depend on periconceptional intake of folate and other micronutrients. The authors mention that confirmation of their observation in other study populations is required, and we agree. We would, however, suggest an adjustment of the categorization of interpregnancy interval, because it is possible that the one used (<12, 12–23, 24–35, 36–47, 48 months) was too broad to reveal any increased risks after short interpregnancy intervals. As a first move, Villamor et al. (1) might want to repeat their analyses with a more fine-tuned classification of short interpregnancy intervals (e.g., categories spanning no more than 3 months). Because short interpregnancy intervals are—at least in principle—avoidable, any risks linked to them should not remain unnecessarily concealed.

National estimates and race/ethnic‐specific variation of selected birth defects in the United States, 1999–2001

In the United States, birth defects affect approximately 3% of all births, are a leading cause of infant mortality, and contribute substantially to childhood morbidity. Population-based data from the National Birth Defects Prevention Network were combined to estimate the prevalence of 21 selected defects for 1999-2001, stratified by surveillance system type. National prevalence was estimated for each defect by pooling data from 11 states with active case-finding, and adjusting for the racial/ethnic distribution of US live births. We also assessed racial/ethnic variation of the selected birth defects. National birth defect prevalence estimates ranged from 0.82 per 10,000 live births for truncus arteriosus to 13.65 per 10,000 live births for Down syndrome. Compared with infants of non-Hispanic (NH) white mothers, infants of NH black mothers had a significantly higher birth prevalence of tetralogy of Fallot, lower limb reduction defects, and trisomy 18, and a significantly lower birth prevalence of cleft palate, cleft lip with or without cleft palate, esophageal atresia/tracheoesophageal fistula, gastroschisis, and Down syndrome. Infants of Hispanic mothers, compared with infants of NH white mothers, had a significantly higher birth prevalence of anencephalus, spina bifida, encephalocele, gastroschisis, and Down syndrome, and a significantly lower birth prevalence of tetralogy of Fallot, hypoplastic left heart syndrome, cleft palate without cleft lip, and esophageal atresia/tracheoesophageal fistula. This study can be used to evaluate individual state surveillance data, and to help plan for public health care and educational needs. It also provides valuable data on racial/ethnic patterns of selected major birth defects.