What is Iniencephaly?
Iniencephaly is a defect of the central nervous system that develops before birth. The condition arises when an embryo’s neural tube, the tissue that eventually forms the central nervous system, develops incorrectly. As a result, the neural tube doesn’t close as it usually does in the first few weeks of pregnancy, resulting in an abnormally formed head, spinal cord, and bones of the spine. Malformation of the brain (anencephaly) is also commonly present.
The condition is almost always fatal to the baby before or soon after birth, typically within a few hours. In addition, Iniencephaly poses a risk to the mother’s life, as the malformations of the baby’s body increase the risk of delivery complications.
Features of Iniencephaly
Iniencephaly results in severe malformations of the baby’s body, including:
- Head bent backward and facing upward
- Neck underdeveloped or entirely absent
- Severe abnormal curvature of the spine
Other central nervous system malformations are sometimes present, such as protrusions of tissue through abnormal openings in the skull (cephalocele). In addition, malformations of other parts of the body, including the heart and gastrointestinal system, can also occur.
What Causes Iniencephaly?
Scientists are not sure what causes iniencephaly. Genetics, environment, and nutrition of the mother during pregnancy all seem to play a role in the development of iniencephaly, spina bifida, and other neural tube defects, but the interplay of all these factors is not well understood.
Research has indicated several risk factors that appear to increase the chance of iniencephaly and other neural tube defects:
- Folate deficiency. When a mother has a nutritional deficiency of folate (also called vitamin B-9 or folic acid) during pregnancy, her baby’s risk of iniencephaly or other neural tube defects increases.
- Family history. Risk increases in families in which previous children have had iniencephaly or other neural tube defects. Risk is also higher when the mother herself has suffered from a neural tube defect. Most cases of iniencephaly, however, occur in babies with no family history of the disorder.
- Obesity and Diabetes. Women who are significantly overweight or have uncontrolled high blood sugar are at higher risk of having a baby with iniencephaly.
- Exposure to high temperatures. The risk of iniencephaly seems to increase if an embryo is exposed to high temperatures during pregnancy. For example, this can occur if the mother has a high fever or uses a sauna or hot tub.
- Drug reactions. Certain anti-seizure medications, such as valproic acid, seem to interfere with the body’s folate processing and increase the risk of neural tube defects when taken by the mother during pregnancy. In addition, the use of some diuretics, antihistamines, and sulfa drugs during pregnancy can also increase risk.
Is Iniencephaly Hereditary?
The role that inherited factors play in the risk of neural tube defects is unclear. Most cases occur in babies with no family history of the conditions. However, the fact that risk increases with a family history of neural tube defects suggests that genetics play some role. Genetic factors are also indicated by the fact that the disorder is more common in females than in males.
How Is Iniencephaly Detected?
Iniencephaly may be detected before birth via ultrasound imaging exams. However, when iniencephalic malformations are detected before birth, they may be mistaken for several other conditions, including:
- Craniorachischisis (anencephaly combined with malformation of the spine)
- Teratomas (tumors that may be either benign or malignant)
- Goiter (enlargement of the thyroid)
- Lymphangioma (malformations of the lymphatic system)
How Is Iniencephaly Diagnosed?
The diagnostic process for iniencephaly typically involves imaging scans during pregnancy and examination of the baby after birth.
Ultrasound imaging scans use high-frequency sound waves to produce a visual image of the fetus. Ultrasound scans may show iniencephaly when performed during the second trimester of pregnancy, but because other conditions can have physical features similar to those of iniencephaly, imaging alone is usually not sufficient for a definite diagnosis.
Although iniencephaly is almost always fatal to the baby, a definitive diagnosis is important because some of the conditions that may be mistaken for iniencephaly have different causes and could affect future pregnancies. Therefore, a postnatal examination to look for the distinctive features of iniencephaly is the only sure way to diagnose the condition.
PLEASE CONSULT A PHYSICIAN FOR MORE INFORMATION.
How Is Iniencephaly Treated?
There is no treatment for iniencephaly. When the condition is diagnosed before birth, the health of the mother becomes a consideration. Termination of the pregnancy before the fetus is viable is an option, but in areas where abortion is illegal, even when the life of the mother is at risk, delivery may be necessary. Cesarean delivery may reduce the risk to the mother in some cases, and vaginal delivery may be induced in the third trimester in other cases.
How Does Iniencephaly Progress?
Iniencephaly is virtually always fatal to the baby. In many cases, the baby miscarries or is stillborn. When the baby survives birth, the condition is usually fatal within a few hours. Researchers have reported a very small number of cases (fewer than ten) in which children with iniencephaly have survived past infancy. Of these surviving children, only three are known to have undergone surgeries to repair the malformations of the condition.
How Is Iniencephaly Prevented?
Women who are pregnant or could become pregnant can reduce their risk of having a baby with iniencephaly or other neural tube defects by proactively addressing several risk factors.
- Ensure an adequate intake of folic acid. The recommended daily dose of folic acid is 400 micrograms (mcg). Women who have had a previous pregnancy with a neural tube defect may be encouraged to take a higher dose. Consult a doctor for guidance.
- Manage diabetes according to your doctor’s instructions, and have blood sugar levels under control before you become pregnant.
- Take steps to control obesity.
- Avoid hot tubs, saunas, and high-temperature environments during pregnancy. Treat high fevers promptly with the over-the-counter fever reducer acetaminophen.
- Tell your doctor about any medications or dietary supplements you’re taking.
Iniencephaly Caregiver Tips
- Take time to process your grief after a diagnosis of iniencephaly. Everyone grieves in their own way, and you shouldn’t hold yourself to anyone else’s standards or schedules. Acknowledge the pain you feel, and don’t be afraid to seek help when you need it.
- Find a community. Online support groups can be a valuable source of information and emotional assistance.
Iniencephaly Brain Science
Much of the research regarding neural tube defects is focused on understanding the genetic component of the disorder. Of particular interest are genes that play a role in the processing of folic acid. A deficiency of the chemical seems to play a vital role in the development of neural tube defects. The most studied of these genes is the MTHFR gene, but several other genes are also associated with folic acid. So far, no consistent link between variations in any of these genes and iniencephaly has been found.
Title: Folate Metabolism in Normal Weight and Obese Women of Child-bearing Age
Contact: Lynn B Bailey, PhD
University of Georgia
Current recommendations established in 1998 specify that all women capable of becoming pregnant consume 400 micrograms of folate daily from supplements, fortified foods, or both, in addition to consuming food folate from a varied diet. Despite this recommendation, obese women have a lower folate status than women of normal weight, which suggests that obesity may have a negative impact on folate metabolism. Therefore, the objective of this study is to determine if there are differences in the metabolic response to a single dose of folate between normal weight and obese women of childbearing age. The two groups of women will be given the currently recommended amount of folic acid, 400 micrograms, and blood samples will be taken before the vitamin is given and at various points afterward to determine serum folate response to the folate dose. Results of this research should help determine if folate requirements are higher for obese than for non-obese women. The long-term goal of this and follow-up studies is to generate data that will contribute to the evidence base used by scientific advisory panels to determine whether dietary folate intake recommendations should be based on body weight.
Title: Genetics of Spina Bifida and Anencephaly
Contact: Allison Ashley-Koch, PhD
This research study aims to discover the genetic and environmental factors that contribute to the cause of neural tube defects such as spina bifida and anencephaly. Ultimately, this type of research may result in improved diagnosis, improved treatment, and possibly prevention.