In April, six organizations filed a petition with the U.S. Food and Drug Administration to take action that could prevent hundreds of birth defects of the spine and brain every year. The request is for folic acid, a B vitamin, to be added to corn masa flour. It demands urgent attention.

The goal is to reduce the incidence of open neural tube defects — spina bifida and anencephaly. The B vitamin, folic acid, is necessary for complete closure of the neural tube that forms the skull, brain and spine of the developing fetus.

Normal development and closure of the embryonic neural tube is completed in the first four weeks of pregnancy. Folic acid taken before conception and in early pregnancy prevents 50 to 70 percent of defects in closure of the neural tube.

The most common neural tube defect (NTD) is spina bifida, in which a portion of the spine fails to close, leaving an open, defective spinal cord, most often in the lower back.

Children with spina bifida have open-spine defects and paralyses of their lower limbs and other organ malfunctions. They require a lifetime of expensive treatments.

Another NTD is anencephaly, in which the skull and brain do not form. The condition is always fatal.

Surviving children with NTDs have tragic and largely preventable developmental abnormalities — devastating for the children and their families, but also for their doctors, nurses and other caregivers. As a practicing obstetrician, I delivered two anencephalic babies — more than enough for me for a lifetime. They constitute my most devastating obstetric experiences.

Women who might become pregnant are encouraged to take a supplement with 400 micrograms of folic acid a day; women who are not planning a pregnancy often don’t follow that advice. A little extra folic acid in staple foods has proved to reduce the prevalence of these birth defects in many countries across the world.

Since 1998, folic acid has been added to enriched wheat flour in the United States; many breakfast cereals are also fortified with folic acid. As a result, the prevalence of neural tube defects such as spina bifida has dropped by one-third.

Hispanics, however, are 20 percent more likely than non-Hispanics to have a child with an NTD. One simple way to address this disparity is to fortify corn masa flour, which is used to make tortillas and tamales, commonly eaten by Hispanic populations. This strategy works because people remember to eat but don’t always remember to take a supplement pill.

After wheat flours and breakfast cereals were fortified with folic acid in the United States, the Centers for Disease Control and Prevention conducted a study to be sure Americans were not getting too much folic acid; it showed that we were not.

The FDA is not required to act within a certain time frame, but the present review process could take two years. That’s too long. It only takes 28 days for a fetal neural tube to develop. Surely we can act on this petition in less than 24 months.

Warren C. Plauche is emeritus professor of maternal-fetal medicine at LSU School of Medicine in New Orleans. He lives in Snellville.