Early in embryonic development, the lip and palate parts are formed by tissues on either side gradually joining together toward the midline. Cleft lip or palate occurs when certain factors interfere early in gestation (before 2 months of age) and the connection is not reached as intended. What exactly causes cleft lip and palate deformities? Most of the causative factors are still unknown, and some patients may be related to genetic or environmental factors.
Genetic factors: Genetic studies have proven that the disease is polygenic, with 20-30% of patients having a positive genetic predisposition. We also often see the occurrence of similar malformations in relatives of patients.
Here is a information on genetic problems: 1. If both parents are normal, the probability of having the first child with cleft lip and palate is 1:550; 2. If both parents are normal and one child has cleft lip and palate, the probability of having the second child with cleft lip and palate is 1:20; 3. If both parents are normal and the first and second children have cleft lip and palate, the probability of having the third child with cleft lip and palate is 1:4; 4. If both parents have a cleft lip and palate, the likelihood of having a child with a cleft lip and palate is 1:20; 5. If both parents have a cleft lip and palate and one child has a cleft lip and palate, the likelihood of having a second child with a cleft lip and palate is 1:4; 6.
Environmental factors: such as vitamin deficiency during pregnancy, viral infection of the mother during pregnancy, exposure to X-rays, hormones or anti-tumor drugs, antihistamines, tobacco and alcohol stimulation, etc., may cause a series of malformations such as mutation of genes.
To sum up, the teratogenic factors are various but not very clear, and can be simply considered as a polygenic hereditary disease. The folklore of mothers cutting cloth, nailing doors, moving houses, moving cabinets, etc. during pregnancy is pure speculation and not enough to be believed. Having a child with a cleft lip and palate is not anyone’s fault, nor is it the parents’ fault, and until medical research has identified the true cause, parents need not feel guilty for having such a child.