Aneurysms and Pregnancy: Vaginal Delivery May Be Safe

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An aneurysm is a weakened, stretched-out part of the wall of an artery or vein that can look like a bubble or a balloon. An aneurysm can exist for years without causing a problem. You may never know you have one and live a long healthy life.

But an aneurysm can turn deadly. The weak spot can break or rupture, which leads to devastating internal bleeding and damage, and possible death. The most serious aneurysm ruptures would be to blood vessels in the brain, where the bleeding would cause brain damage. A brain aneurysm that ruptures is one type of stroke. Another serious type of aneurysm would be one that occurs in the aorta, the largest blood vessel in the body, which runs from the heart down through the chest and abdomen.

According to the Centers for Disease Control and Prevention, around 30,000 people die from brain aneurysms and about 25,000 people die from aortic aneurysms each year in the United States. According to the Brain Aneurysm Foundation, about 6.5 million people in the United States have an unruptured brain aneurysm (about 1 in 50 people). Women are a bit more likely than men to have a brain aneurysm, according to the foundation, but are less like to develop an aortic aneurysm than men, according to the Mayo Clinic.

Several things can cause aneurysms to develop. You may have been born with a weakened spot on an artery that starts to develop into an aneurysm as you grow older. The common causes of aneurysms that develop on their own are high blood pressure and atherosclerosis (deposits of fat that clog the arteries). A deep wound or infection can also weaken a spot on an artery that then develops into an aneurysm.

An aneurysm that doesn’t rupture may have no symptoms at all. Symptoms for a brain aneurysm that ruptures include a seriously bad and sudden headache, nausea and vomiting, a stiff neck, blurred or double vision, or a seizure. Because a ruptured brain aneurysm is a type of stroke, it has many of the same symptoms like a drooping eyelid or side of the face, or weakness in the arm or leg on one side of the body. Symptoms of an aortic aneurysm include sudden intense pain in the chest of pack, low blood pressure, shortness of breath or trouble breathing, and loss of consciousness.

Aneurysms and Pregnancy

So, what do aneurysms have to do with pregnancy? The good news is that the vast majority of pregnant women never have to worry about them because despite the scary numbers we gave you, they are still rather rare in healthy people under age 35. However, if a pregnant woman has an aneurysm, there is the possibility that it could rupture during pregnancy and childbirth. For this reason, women who were known to have an aneurysm have been advised to have a cesarean section birth.

But a study found that a cesarean section may not be needed for women who have an aneurysm. Dr. Brian Hoh of the University of Florida and his colleagues used information from a large national database to estimate the risk of a rupturing a brain aneurysm during pregnancy and childbirth. They found 714 cases of women who were hospitalized for a ruptured aneurysm during pregnancy between 1988 and 2009. They also found cases of 172 women who had a ruptured aneurysm during delivery in that time period.

Using that data, they estimated there was a 1.4% risk of aneurysm rupture during pregnancy and 0.05% risk during delivery. These rates were about the same as the risk of an aneurysm rupture in the general population, the study found. In addition, they found that there was no evidence that having a cesarean delivery improved the outcome for either the mother or the baby.

This means that a woman with a known aneurysm can deliver vaginally if she and her obstetrician have no other reasons to have a cesarean section.

If a brain aneurysm ruptures, there is a serious risk of death or brain damage. The same study found that a rupture in a pregnant woman or one who just gave birth can be treated. Treatment for a ruptured aneurysm can be done by either surgically closing the weakened area of artery with a metal clip or threading a catheter into the ruptured blood vessel and inserting a coil of very thin wire to close off the rupture.

Valerie DeBenedette
Valerie DeBenedette is an experienced health and medical writer who lives about an hour north of New York City with a dog that is smaller than her cat. Her work has appeared in magazines, newspapers, newsletters, and on websites. She is a member of the National Association of Science Writers.

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