What Are the Most Common Fetal Defects?

Fetal malformations are structural or chromosomal abnormalities that occur in the womb. Fetal malformations account for about 3% of live births. About 5 million birth-deficient babies are born every year around the world, with an average of one every 5 to 6 minutes, and more than 85% occur in developing countries. The total number of children with congenital disabilities in China is as high as 800 to 1.2 million, accounting for 4% to 6% of the total number of births in China. Severe deformities can cause fetal / newborn death or severe disability.

Basic Information

English name: fetalanomaly
Visiting department: Obstetrics and Gynecology

Common causes: Maternal or environmental factors, genetic factors
Common symptoms: 21-trisomy syndrome, congenital heart disease, neural tube defects, cleft lip and palate, multi-finger / toe, hydrocephalus, etc.

Causes of Fetal Malformations

1.Maternal or environmental factors

(1) When the radiation dose absorbed by the fetus during early pregnancy exceeds 5rad, the risk of fetal malformation will increase significantly;

(2) Chemical agents Certain drugs can cause fetal malformations, especially when used during early pregnancy. Therefore, medications during pregnancy should be administered rationally under the guidance of a doctor. Rural women should avoid exposure to pesticides during pregnancy. Long-term heavy drinking can cause fetal alcohol syndrome, manifested by microcephaly, mental retardation and special facial features. Heavy metals (mercury, lead, etc.) increase the risk of fetal malformations.

(3) Infection During pregnancy, infection of certain microorganisms by the mother can cause fetal infection and fetal malformations, such as rubella, giant cells, herpes simplex, toxoplasma, and syphilis.

(4) High fever during early pregnancy.

(5) Poor blood glucose control in pregnant women with hyperglycemic diabetes during pregnancy can increase the risk of fetal malformations, mainly congenital heart disease, neural tube defects, cleft lip and palate.

(6) Dietary factors Folic acid deficiency in food increases the risk of fetal neural tube defects and cleft lip and palate.

2. Genetic factors

Abnormality caused by abnormal genetic material from parents. Such as: parents chromosomal abnormalities, parents carrying mutant genes and so on. Sometimes the fertilized egg itself has an abnormal chromosome segregation or a genetic mutation. When close relatives marry, because the risk of both spouses carrying the same abnormal gene increases, leading to a significant increase in the incidence of some recessive genetic diseases, it is not appropriate for close relatives to get married or have children.

Clinical manifestations of fetal malformations

The most common fetal malformations include: trisomy 21, congenital heart disease, neural tube defects, cleft lip and palate, multi-finger / toe, hydrocephalus, etc.

Fetal malformation

At present, screening of major fetal malformations in China during pregnancy mainly includes: trisomy 21, trisomy 18, open neural tube defects, anencephaly, severe hydrocephalus, and some severe congenital Heart disease, etc.

Fetal ultrasound

It is a common method for detecting fetal malformations. Generally, it is checked at 20 to 24 weeks of pregnancy. All fetal organs can be clearly shown by B-ultrasound. If the B-ultrasound finds a serious fetal malformation at this time, it should be aborted in time to avoid delay By the end of pregnancy, it will cause greater pain to pregnant women. However, not all deformed fetuses can be detected by B-ultrasound. B-ultrasound can't be detected by congenital stupidity or some minor deformities due to chromosomal abnormalities; some deformities can only be shown in late pregnancy; due to ultrasound Due to limited resolution and technical reasons, some malformations may be missed during ultrasound examinations.

2. Fetal magnetic resonance examination

Because of its characteristics of multi-bit imaging, high soft tissue resolution, no radiation, and fetal safety, magnetic resonance has broad prospects in obstetric applications. And it has become an important means of verification and supplementary diagnosis of fetal abnormalities detected by ultrasound in prenatal diagnosis. Especially in the diagnosis of fetal central nervous system abnormalities, such as the identification of cerebral hemorrhage and other aspects have more outstanding performance.

3. Interventional prenatal diagnosis

Through techniques such as amniotic fluid puncture and umbilical cord blood puncture, chromosome karyotype analysis and genetic testing can be performed on fetal cells to diagnose certain fetal congenital diseases.

Diagnosis of fetal malformations

Through fetal system ultrasound, amniocentesis and other prenatal diagnostic techniques, many malformed fetuses have been diagnosed in utero. However, the current prenatal diagnosis rate for fetal malformations is not satisfactory. The main reasons are: some malformations are difficult to find in the uterus; the limitations of the antenatal diagnosis technology itself; the medical conditions limit the prenatal diagnosis Difficult to carry out widely.

Fetal malformation treatment

Most non-fatal deformities do not require surgical intervention during pregnancy, such as congenital heart disease, and can be treated after birth. However, some fetal malformations may affect the intrauterine safety of the fetus and require intervention during pregnancy. Due to the high risk of surgery and high technical requirements, most intrauterine treatments of fetuses are still in the experimental stage.

Intrauterine therapy

Fetal scope surgery is mainly used to treat twin blood transfusion syndrome or fetal reduction surgery. There are reports abroad for the treatment of fetal diaphragmatic hernia, meningocele, urinary tract obstruction and so on.

2. Postpartum treatment

Such as hydrocephalus shunt surgery, cleft lip and palate repair, surgical treatment of congenital heart disease, phenylketonuria drug treatment and so on.

Fetal malformation prevention

1. Pre-marital medical examination. Some diseases found through the examination, such as hepatitis B and sexually transmitted diseases, will affect the health of the offspring, cause fetal malformations, and only become pregnant after curing

2. Make preparations for pregnancy, prepare for a planned and planned pregnancy, and perform some necessary tests, such as rubella virus testing. Rubella virus infection can cause fetal congenital heart disease and congenital deafness, cataracts and other deformities. Rubella vaccine can be used to prevent rubella virus infection.

3. Taking folic acid before pregnancy: Taking folic acid in the first three months of pregnancy can effectively prevent fetal neural tube defects.

4. High-risk pregnant women should undergo prenatal consultation.

5. Regular postpartum checkups during pregnancy: Avoid exposure to adverse environments and drugs, quit drinking and smoking, do Down's screening, B-ultrasound, etc. Perform prenatal diagnosis if necessary to detect fetal malformations in a timely manner.

6. When you need medication, you should consult your doctor to avoid improper medication affecting the fetus.