Cleft lip and palate, commonly known as “hare lip”, is one of the most common congenital malformations of the oral and maxillofacial region. Numerous experimental studies and epidemiological findings have shown that cleft lip and palate is caused by multiple factors rather than a single factor. Broadly speaking, it can be divided into two aspects: genetic and environmental factors, and is related to nutritional, genetic, infectious and endocrine factors. In early pregnancy, pregnant women are affected by related factors, which can affect the development of the lip and palate, leading to the occurrence of cleft lip and palate.
A. The etiology of cleft lip and palate
1, genetic factors: in the immediate family or collateral relatives of cleft lip and palate patients sometimes have similar deformities, so it is believed that cleft lip and palate deformity and genetics have a certain relationship. Epidemiological investigations have shown that the incidence of cleft lip and palate in the offspring of those with cleft lip and palate deformities in the immediate family is higher than that of those without cleft lip and palate deformities in the relatives. Genetic studies have also concluded that cleft lip and palate is a polygenic hereditary disease, rather than a single gene causing the disease.
2, environmental factors: mainly refers to the environment in terms of embryonic growth and development, the entire physiological state of the mother constitutes the environmental conditions for embryonic development. The development of the lip and palate is basically completed in the first trimester of the embryo; therefore, when the physiological state of the mother is invaded or disturbed during the first trimester of pregnancy, it may affect the growth and development of the embryo’s jaw and face, thus leading to the occurrence of cleft lip and palate.
①Nutritional deficiencies: In experimental animal studies, it was found that mice deficient in food components such as vitamin A, B2 and folic acid can produce malformations such as cleft lip and palate, while it is not clear whether congenital malformations can also occur in humans due to deficiencies of such substances. Therefore, nutritional deficiency in early pregnancy may be one of the triggers for the development. It is recommended that folic acid and vitamin supplements may be appropriate before and during pregnancy.
②Infection and injury: If the mother suffers some kind of injury in the early stage of pregnancy, especially injury to the uterus and its adjacent parts, such as improper incomplete abortion or unscientific drug abortion, it can affect the development of embryo and lead to malformation. Maternal viral infections such as rubella can also affect the development of the embryo and become a possible cause of cleft lip and palate.
(iii) Endocrine influences: Infants born after hormone therapy during the first 3 months of pregnancy have some congenital malformation. In the investigation of the family history of children with cleft lip and palate, it was also found that some mothers had various obvious traumatic factors in early pregnancy, and it is inferred that this may lead to a stress response, resulting in increased secretion of adrenocorticotropic hormones in the body and inducing congenital malformations.
④Drug factors: Most drugs can enter the embryo through the placenta after entering the mother’s body. Some drugs may affect the development of the embryo and cause malformation. It is known that antitumor drugs such as cyclophosphamide and methotrexate, anticonvulsant drugs such as phenytoin sodium, antihistamines and Minkajin for pregnancy vomiting and some sleeping drugs such as thalidomide can cause fetal malformation.
⑤ Physical injury: During the fetal development period, frequent exposure to radiation or microwaves may affect the growth and development of the fetus, leading to the occurrence of cleft lip and palate.
(6) Alcohol and tobacco factors: heavy smoking and alcohol abuse in early pregnancy have a higher incidence of cleft lip and palate in their children than in women without alcohol and tobacco habits.
The teratogenic factors of cleft lip and palate are diverse and not yet clear, and can be simply considered as a polygenic genetic disorder. And folklore says that factors such as the mother cutting cloth, nailing doors, moving house and moving cabinets during pregnancy are purely feudal superstition.
Second, how should I prevent cleft lip and palate?
1, pre-conception examination: cleft lip and palate is a polygenic genetic disease, before pregnancy, it is important to conduct a comprehensive and detailed pre-conception examination.
2.Healthy pregnancy: Since the development of lip and palate is mainly in the first trimester of pregnancy, the mother may cause genetic mutation and lead to cleft lip and palate if she is infected with virus, taking certain drugs, exposed to X-rays or lack of oxygen in early pregnancy.
3. Nutritional balance: The mother is the only source of nutrition for the fetus. During pregnancy, a balanced and diversified diet is very important. Eat more vegetables and fresh fruits while pregnant, and less food containing sugar, salt and processed foods.
4, mood relaxation: when pregnant women have bad moods such as worry, anxiety, irritability and fear, adrenocorticotropic hormones may prevent the fusion of certain tissues of the embryo, resulting in fetal cleft lip or palate.
5.Early treatment of systemic diseases: If pregnant women have diabetes, anemia, gynecological diseases and hypothyroidism diseases, they should be treated as early as possible to ensure that the corresponding indicators are within the normal range.
6.Consult your doctor before using drugs: Since many drugs can pass the placental barrier and thus affect the development of the fetus. Therefore, you should try not to take drugs during pregnancy, if you must serve you need to consult your doctor and try to use drugs that cannot pass the placental barrier, such as penicillin, cephalosporins, etc.
7, avoid colds: research found that many mothers of cleft lip and palate patients have had symptoms of colds in early pregnancy, and even take drugs to treat colds, which is one of the important factors leading to the occurrence of cleft lip and palate.
8, away from viruses: viral infections can significantly affect the growth and development of the fetus, so women during pregnancy should stay away from or guard against viral infections, such as rubella and other viral infections.
9, away from radiation: both men and women in the first three months of the decision to get pregnant, try to avoid contact with radioactive supplies, away from computers, cell phones to board a large amount of radiation of electronic products, if necessary, use protective equipment.
10, quit smoking and alcohol: smoking and alcohol consumption is one of the high-risk factors for the occurrence of cleft lip and palate. Epidemiological surveys have found that smoking or drinking alcohol can make the risk of cleft lip and palate several times higher. Therefore, before pregnancy and during pregnancy should avoid exposure to smoking and alcohol and other harmful factors.
11, pay attention to marriage and maternity checkups: Although marriage checkups are not mandatory in China at present, it is best to conduct the first screening through marriage checkups before marriage to detect genetic diseases such as cleft lip and palate. In addition, fetal development to 20 to 24 weeks can be seen from the ultrasound examination whether the fetus has limb stumps and other more obvious deformities.
PS:
Cleft lip and palate, commonly known as “harelip”, is mostly known as a congenital malformation. But there is a legend in South Africa that children with cleft lip and palate are little angels who were kissed by God, who left a hickey – a mark of distinction for these little angels, or “angel’s kiss” – the name of a cocktail. Angel’s Kiss is probably the most unusual and emotional name for a disease.