In 2015, a couple from Texas received news during a routine ultrasound that their baby had anencephaly, a fatal birth defect that results in the fetus being born without parts of the skull or brain. Their doctor advised them to terminate the pregnancy, due to the fact that anencephaly has a 100% mortality rate, but the couple decided to carry the fetus to term. After a total of 39 weeks of pregnancy, the baby was born and 10 and a half hours later, died. Cases like this affect a number of families every year and can often be prevented through proper consumption of folic acid.
In this particular case, the infant had anencephaly, which is a type of open neural tube defect (NTD) that is localized in the brain; NTDs are defects where the brain and/or spinal cord is exposed at birth due to improper closure of the neural tube. The neural tube develops three to four weeks after conception and later forms the brain, skull, spine and spinal cord. Another type of open NTD is called spina bifida which is localized in the spinal cord and results in varying degrees of severity depending on the size and location of the opening. Some cases can be mild, with 15% of the healthy population unaware that they have a mild case, whereas others may require constant treatment and have a life-long disability. Neural tube defects occur in approximately one in 1,000 live births in the United States every year, with anencephaly and spina bifida being the most common.
The most effective way to prevent NTDs is by having pregnant mothers take folic acid supplements, which have been found to prevent up to 70% of NTDs. Folic acid is the synthetic form of vitamin B9, which can also be referred to as folate. In general, folate aids in DNA and RNA synthesis, protein metabolism and the production of red blood cells, however the specific mechanisms that describe how folic acid prevents NTDs have yet to be discovered. Currently, research has shown that most women who had a pregnancy affected by NTDs were not folate deficient, but rather genetic defects in folate absorption and metabolism caused the formation of NTDs. In these cases, it is recommended to increase folate intake through folic acid supplements to compensate for the ineffective usage by the body.
Folate can be consumed in its natural form through food such as green leafy vegetables like spinach, broccoli and brussels sprouts or as folic acid in supplements. The drawbacks with using diet as the only source of folate are that it can be harder to manage how much folate is being consumed and ensure that it is above the recommended daily amount. Additionally, folate in the form of folic acid is better absorbed by the body, at a rate of 85%, while only 50% of folate from food is able to be absorbed.
The CDC recommends that all women of reproductive age take 400 micrograms of folic acid everyday as a precaution in case of an unplanned pregnancy. The neural tube forms roughly three to four weeks after conception, so women may not realize that they are pregnant until after the neural tube has formed. At this stage, it is too late to take preventative measures against NTDs and the fetus is at risk of being born with certain birth defects. For women who are planning on getting pregnant, it is recommended that they start taking folic acid at least one month before conception and through the first three months of pregnancy. For women who previously had a pregnancy affected by NTDs, there is a 2 to 3% chance of having another pregnancy affected by NTDs. The recommended amount of folic acid in these cases is 4,000 micrograms or four milligrams which can only be obtained with a prescription while 400 micrograms of folic acid are found in over-the-counter supplements.
Before taking folic acid or starting a folate-rich diet, women should talk with their obstetrician to create an individualized vitamin regimen. Diet, lifestyle and genetics all impact fetal development, so finding a balance with the help of medical professionals can help reduce the occurrence of birth defects like NTDs.