Abstract Objectives Orofacial clefts are among the most common birth defects, with
an estimated worldwide incidence of around 1.5-1.7 per 1000 live-born babies. The
most frequent form of orofacial clefts is cleft lip with or without cleft palate (CL?±?CP).
The role of environmental factors in the development of clefts is unclear in most
patients, thus the aim of this study was to estimate possible maternal risk factors
in the origin of CL?±?CP. Materials and Methods 1648 CL?±?CP cases, 2654 matched controls
and 57?231 population controls were evaluated from The Hungarian Case?Control Surveillance
of Congenital Abnormalities. Maternal factors during the critical period in cases
and controls were compared. Adjusted odds ratios (OR) with 95% confidence intervals
(CI) were estimated in a multivariable conditional logistic regression model. Results
Among socio-demographic data, we have found significant differences between maternal
employment. The proportion of unskilled mothers (6.5%) were higher in the CL?±?CP
group than in controls (3.5%). Medically recorded maternal anaemia, excessive vomiting
and threatened abortion were associated with a higher risk of CL?±?CP. An elevated
risk was also found in various acute illnesses such as influenza (OR: 2.4, 95% CI:
3.0-5.8), acute bronchitis (OR: 4.5, 95% CI: 1.6-12.6) and urinary tract infections
(OR: 3.5, 95% CI: 2.0-6.0). Maternal migraine and essential hypertension occurred
more frequently in the mothers of cases than in controls. Conclusion The findings
of this study suggest that maternal diseases and lifestyle factors during the first
trimester play a significant role in the development of CL?±?CP.
