Fetal Abnormalities: What You Need to Know

Giving birth to a baby is the most beautiful experience of a woman’s life. Pregnancy is a painful and at the same time a beautiful experience that many women cherish. But there can be lots of complications involved in conception and then during the pregnancy. There can be many things that can occur to the fetus.

Most of the problems that happen during conception are due to chromosomal errors that cannot be rectified in most cases. Due to the problems in the early pregnancy period, fetal malfunctions can occur.

The chances of fetal abnormalities are more when you have a family history of birth defects or genetic disorders. If you are consuming drugs or alcohol during your pregnancy, it can cause fetal abnormalities. Fetal abnormalities can occur in women who have untreated bacterial infections that include sexually transmitted diseases during the pregnancy. In some women, taking powerful medicines during the pregnancy can lead to fetal abnormalities.

Studies have proven that it is not always possible to prevent birth defects, but we can reduce their severity. Taking folic acid before and during the pregnancy can help in avoiding birth defects related to the brain and spine of the baby. Some doctors may advise taking prenatal vitamins during the pregnancy to improve the health of the baby and mother.

Here we look at the 15 fetal abnormalities that can occur during the pregnancy.

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15 Achondroplasia

Achondroplasia is a fetal abnormality that occurs during early fetal development. If a newborn has Achondroplasia, then most of the cartilage, which is normally converted to bones, does not convert. The condition is usually noticed at the time of birth. The torso is unusually long and the limbs are short in comparison.

Achondroplasia is caused by the mutations in the FGFR3 gene and this causes the proteins to be overactive. If one of the parents has a shortage of FGFR3 gene, the chances of Achondroplasia are more than 50 percent in the newborn. In many cases, these fetal abnormalities cause death. The average height for adults with the disorder is 4’4” and they usually have bowed legs, poor muscle tone, and joint problems. Worldwide, it is estimated that 1 in every 100,000 births results in a child with achondroplasia. Children will be delayed in reaching some growth and motor skill milestones, but intelligence is normal.

14 Trisomy 18

Trisomy 18, also known as Edward’s Syndrome, is another disorder that can occur in a fetus due to chromosomal abnormalities. When the mother’s egg or the father’s sperm contains the wrong number of chromosomes, this error is passed on to the baby. Trisomy 18 means that the baby has 3 copies of chromosome 18. The most common type is full Trisomy 18 in which every cell in the baby’s body carries the extra chromosome.

Babies with Trisomy 18 can have problems with their kidney, heart, and lungs. A small head and weak cry are the other common problems seen in babies with Trisomy 18. During an ultrasound scan, the doctor may be able to identify if the baby has the Trisomy 18 disorder. There is no treatment for the Trisomy 18 disorder. The survival rate is very low and many don’t live past the first or second trimester. Those that do survive rarely make it to their first birthday.

13 Sickle Cell Disorder

Sickle Cell Disorder is another fetal abnormality that is a hereditary disorder. Sickle cell disorder is passed from both the parents to the baby. This disorder causes red blood cells to form in a sickle-like shape. The sickle shape of the cells hinders their ability to carry oxygen to the different parts of the body. Also, the cells are somewhat brittle and sharp. They can get caught in small blood vessels and cause pain and damage to the organs such as the heart, lungs, liver, kidneys and bones.

This disease is seen mostly in those of African descent but is also present in those from Mediterranean countries such as Greece, Italy, and Turkey. Also, those from the Spanish-speaking areas of Central and South America, parts of the Caribbean and people from India and the Arabian Peninsula.

Your baby will receive a routine blood test after birth, and if it shows sickle cell, a second, different blood test will be run to confirm. With modern medicine, children with sickle cell disease can grow up and live longer lives.

12 Tay-Sachs Disease

Tay-Sachs disease is considered a rare but dangerous genetic disorder that can be seen commonly in children. It causes progressive destruction of the complete nervous system. The destruction process will start in the fetus during the initial stages of the pregnancy. Children with this disease lack an enzyme that breaks down the fatty waste found in the brain cells. This waste accumulates and causes damage to the nervous system to the point it can no longer keep the body alive.

The baby looks normal when born and development of the baby slows down between three and six months of age. The child will begin to lose motor skills and have an exaggerated response to loud noises. A child affected by the Tay-Sachs disease usually dies by the age of 5 as the nervous system will be completely damaged by then. As of now, there is no cure for Tay-Sachs disease.

11 Anencephaly

Anencephaly is a serious disorder related to the central nervous system. In this condition, the cranial vault and brain are not correctly formed. The hindbrain is present, but the cerebellum and cerebrum are not present or not fully formed.

Anencephaly results when the neural tube fails to close during the early days of development of the fetus. Usually, it results in a fetal loss, neonatal death or stillbirth. Anencephaly is fairly rare and it is estimated that there are less than 20,000 cases per year. Most cases result in miscarriage. The disorder is usually found in  the first or second ultrasound and many mothers are encouraged to abort the fetus. However, there are many cases where children have lived past one year of age. Research has shown that a lack of folic acid in the diet increases the chances of having a baby with anencephaly. It is recommended by that all women who are considering becoming pregnant and those who are pregnant make sure they get the correct amount of folic acid in their diet.

10 Open Spina Bifida

Open Spina Bifida is another form of neural tube defect. Normally, the neural tube is formed in the early days of pregnancy and is closed on the 28th day after conception. The fetus with open spina bifida has a portion of the neural tube that is not fully developed or closed correctly. As with other neural tube abnormalities, there is no known cause. The term comes from the Latin “spina,” which means spine, and “bifida” meaning “split.”

The severity of Open Spina Bifida varies from child to child. Studies have proven that girl children are more prone to open spina bifida and women who had open Spina Bifida or a family history of it have the highest chances of giving birth to a baby with the Spina Bifida disorder. Studies have shown that taking folic acid before and during the pregnancy and following a healthy diet can help in reducing the risk. Surgery can remedy the condition.

9 Cleft Lip and Cleft Palate

A cleft lip occurs when the two sides of the babies face fail to meet in the middle during the second to seventh week of growth within the womb. It may or may not be accompanied by a cleft palate. A cleft palate occurs when there is a gap or opening in the roof of the mouth. It happens during the early formation of the fetus when the roof of the baby’s mouth does not close properly. This makes it very difficult for babies to feed because of the difficulty in maintaining suction and can lead to numerous ear infections.

A cleft palate (or a cleft lip) has affected more than 7,000 babies every year. Both conditions can be fixed with surgery. Like the majority of birth defects, research has not found a specific cause. The Centers for Disease Control and Prevention has been doing extensive research and have found that smoking, diabetes and certain medications (specifically for epilepsy) increase the risk.

8 Congenital Heart Disease

Congenital heart disease is a serious disorder that can occur in your baby during the early days of pregnancy. It is considered that around 1 percent of babies born in America are suffering from congenital heart disease and it is the most common form of birth defect. There are actually many different kinds of congenital heart disease and many do not show up until later in life. If an abnormality is noticed during a normal ultrasound, you will be referred to a pediatric heart specialist who will do further testing and discuss the results with you and possible steps to take after birth.

Even though the exact reason for the disorder is still unknown, women with a family history of heart-related diseases have a high risk of giving birth to a child with heart disease. You can detect if your baby has congenital heart disease with the help of a fetal echocardiogram. The severity of congenital heart disorder can range from mild to severe and the treatment is based on how severe the condition is after the baby is born.

7 Heart Rhythm Problem

Another serious heart disorder associated with a fetus is a heart rhythm problem. A normal rhythm for a fetus is between 120 and 160 beats per minute. However, fetuses with rates as slow as 90 is not a cause for concern. Fetuses may suffer from bradycardia, a heart rate that is too slow, or tachycardia, where the heart rate is too fast. Most cases remedy after birth. However, some with tachycardia may require medication, through the mother and close supervision. Some fetuses may suffer actual heart defects that cause an interruption in the electrical connection between the two parts of the heart, the upper part and the lower part.

There is only a remote chance that a fetus may die due to a heart rhythm problem. In most cases, after the delivery of the baby, treatment can be done to correct the disorder. Even though the exact cause of the heart rhythm problem is unknown, consuming a lot of caffeine during pregnancy is not good for your baby’s heart.

6 Gastroschisis

Gastroschisis is another genetic disorder occurring in the fetus during the early days of pregnancy when the baby’s abdominal (belly) wall is not formed correctly. Here, the baby’s intestines form outside of the body, through a hole in the belly.

The size of the hole can be small or big and in some rare cases other organs, such as the liver and stomach also come out through this hole. Since the intestines are not protected by the abdominal wall, they are exposed to the amniotic fluid and can become irritated causing twisting, swelling or shortening.

The survival rate of babies suffering from Gastroschisis is high. The condition is usually found during normal ultrasound sessions and so a surgical team can be ready to go after the baby’s birth. The baby will undergo surgery to put all the organs inside and the child can lead a normal life. The exact reason for Gastroschisis is not known, but smoking during pregnancy can increase the risk.

5 Congenital Diaphragmatic Hernia

CDH or congenital diaphragmatic hernia occurs when the diaphragm is not completely formed in the fetus. Newborns with the disorder usually have extreme trouble breathing, which is life threatening without treatment. The diaphragm is the flat muscle that separates the abdominal cavities from the chest. In most cases, CDH occurs on the left side. When the abdominal organs move up into the chest cavity through the hole in the diaphragm, it constricts the ability of the lung’s growth. Underdeveloped lungs cause reduced blood flow to the lungs and results in pulmonary hypertension as well. This can lead to gastrointestinal reflux, developmental delays, feeding disorders and asthma. Infants with this defect often die of pulmonary hypoplasia, or decreased lung volume, leading to not enough oxygen, and pulmonary hypertension, or increased blood pressure in the lungs.

The defect is often found during a routine sonogram. Depending on the severity of the problems, fetal intervention can help, meaning surgery while the fetus is still inside the mother. This can correct the problem and allow the lungs to develop more normally.

4 Trisomy 13

Trisomy 13 or Patau Syndrome is another chromosome related abnormality that can be seen in the fetus. It is caused by an additional number 13 chromosome, rather than the normal two. It can appear in every cell of the body or only in some cells, called mosaic variations. Infants with mosaic variations are less affected and have a higher chance of survival. However, survival rates are low with a 50 percent chance of infants living past the first 13 days. However, there are known cases where children have lived to the age of 10.

Infants born with this disorder suffer from extensive abnormalities that can affect nearly every organ in the body. The brains of babies with trisomy 13 are poorly formed. Eye defects, cleft palate and lip and heart defects are most common. Many suffer from spina bifida and all suffer from developmental delays. Although the exact cause is unknown, some research has shown that the incidence increases with the mother's age.

3 Skeletal Dysplasia

Skeletal dysplasia is a medical condition that can occur in your child and can affect the growth of the bones and the cartilage. It is a genetic defect that is caused by the defect of a particular gene. There are actually many types of skeletal dysplasia, sometimes referred to as dwarfism or simply a disproportionate short stature. The different types are categorized depending on the particular gene that has the defect. If a person is of short stature and proportional, they usually suffer from a metabolic disorder.

A child born with skeletal dysplasia can have lots of differences in the size and shape of the legs, arms and the skull. They are usually short in nature. They may have missing ribs and limbs and experience fractured bones easily. The exact genetic defect that can cause skeletal dysplasia can be difficult to point out. A doctor can diagnose the problem during the fetal formation but the type of skeletal dysplasia can be measured only after the child is born.

2 Chromosome Abnormalities

Sometimes the abnormalities can be in the chromosomes and sometimes in one or more genes. Gene abnormalities do not cause any abnormality in the fetus unless the abnormal gene is inherited from both the parents. If there is one copy of a defective gene in a pair, the good copy from the other parent takes over. The majority of chromosome disorders are from the gain or loss of an entire chromosome and this affects hundreds or thousands of genes and usually end in death and miscarriage. The mechanism that allows some fetuses to survive and not others is not understood at this time.

Down’s syndrome or Trisomy 21 is the most common chromosome abnormality that can be seen in the fetus during the initial days of development. This is when there is a third copy of chromosome 21 in the genes. If you have delivered a baby with Down’s syndrome earlier, than the risk of having another baby with Down’s syndrome increases by three-fold.

1 Cystic Fibrosis

Cystic Fibrosis is a life-threatening disorder that can occur in newborns. A child with Cystic Fibrosis has a faulty gene. Due to the faulty gene, the movement of sodium chloride is affected. That results in thick and sticky mucus that will block the movement of oxygen in the lungs and cause breathing problems. The disease also affects the production of sweat and digestive juices. Instead of acting as a slippery lubricant, fluids become thick and plug airways and other passageways in the body, including the pancreas.

If any of the parents are suffering from cystic fibrosis, then it is very important to conduct tests to identify if the fetus has cystic fibrosis. Parents usually play the role of the carrier and can easily transfer CF to their babies. Although the disease is serious and requires daily care, people with the disease go on to live full lives, often living into their 50s.

Sources: National Institutes of Health, BabyCenter, Healthline, Livestrong, WebMD, Genome.gov, E Medicine, Mayo Clinic, Heart.org, American Pregnancy, CDC, UCSF.edu, Net Doctor

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