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Pregnancy and Reproduction
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Couples considering pregnancy are advised to understand how Marfan syndrome is inherited in families so they know the risk of having a child with the disorder. If either parent is affected, each pregnancy has a 50-50 chance of producing an affected child. In addition, affected women considering pregnancy should understand the medical risks and special care needed to manage a pregnancy. The following are common questions to consider regarding pregnancy and Marfan syndrome:
Q&A Q & A I have Marfan syndrome and I want to have a baby. What should I do before I become pregnant?
There are several things to consider before becoming pregnant: - Have an examination with your family doctor or internist to evaluate your overall health.
- Visit your cardiologist and have an echocardiogram to make sure your aorta is not at a size that would make pregnancy too risky.
- See a perinatologist (maternal-fetal medicine specialist or high risk obstetrician) to talk about specific issues related to pregnancy and Marfan syndrome.
- Consult with a clinical geneticist or genetic counselor to help you and your partner understand how Marfan syndrome is inherited and to learn about the choices you have.
Am I at greater risk of medical problems while I am pregnant?
All women with Marfan syndrome are at increased risk for complications during pregnancy. Therefore, it is important that you are cared for by an obstetrician with the experience and expertise needed to manage potentially life-threatening heart problems. You should also be carefully followed by your cardiologist throughout the pregnancy, with echocardiograms done at least every three months.
There are not a lot of studies in this area, but available research shows that: - Women with an aortic root less than 4.0 cm are at very low risk for a rapid change in aortic size or aortic tear during or immediately after pregnancy.
- Women with an aortic root above 4.0 cm are at greater risk, and this risk appears to increase proportionally to aortic size.
- Women with Marfan syndrome with an aortic root of more than 5.0 cm are at extreme risk during pregnancy. In this case, pregnancy is not recommended.
Am I more likely to have a miscarriage due to Marfan syndrome?
The miscarriage rate in women with Marfan syndrome is no different than that in the general population. What is the chance that my baby will have Marfan syndrome?
When one parent has Marfan syndrome, each child born has a 50% chance of being affected by the disorder, regardless of the sex of the child or the affected parent. If both parents are affected, there is a 75% risk that the child will be affected. A child who inherits the Marfan gene from two affected parents would be severely affected. Is there any way to make sure I have a baby that does not have Marfan syndrome?
There are two basic approaches a couple might use to have a baby without Marfan syndrome. One uses amniocentesis or chorionic villus sampling of the fetus early in pregnancy to determine if the fetus is affected. The other uses in-vitro fertilization with pre-implantation genetic diagnosis. Both methods require knowledge of the location of the parental mutation as determined by either mutational or linkage analysis. For a description of these tests see Molecular Testing for Marfan Syndrome. Either method takes time to obtain the test results. Therefore it is important to undergo the testing prior to becoming pregnant. Since this is a complex and rapidly changing area of medicine, prospective parents should discuss the latest status of available options with their doctors and genetic counselors. Is there anything special I need to do during pregnancy?
A woman with Marfan syndrome should have an echocardiogram before she becomes pregnant. While she is pregnant she should have an echocardiogram once during the first two months and at least once in each trimester.
If a woman’s aorta measures close to 4.0 cm, more frequent echocardiograms are recommended (every 6-8 weeks) to check for any sudden increase in the size of the aorta. Women who experience a significant increase in their aortic root diameter during the course of the pregnancy should also have more frequent echocardiograms. I am currently on coumadin (or another anticoagulant). Can I continue to take this medication while I am pregnant?Coumadin has been associated with birth defedts if taken during the 7th - 11th week of a pregnancy. For this reason, in the United States, women with Marfan syndrome who require anticoagulation during pregnancy are generally placed on another kind of medication, heparin, which does not cross the placenta and is not associated with birth defects. Frequent monitoring of the time it takes the blood to clot (prothrombin time, PTT) is necessary to make sure that the blood is thin enough and won’t clot. Heparin is stopped briefly for 24 -48 hours surrounding the time of birth.
Coumadin can be safely used while breast-feeding because the level of the medication that is in breast milk is very low and does not have any anticoagulation effect in the infant.
Therefore, after delivery, heparin should be restarted and Coumadin also started. The heparin can be discontinued once the Coumadin has reached the level where it has its desired effect.
Pregnancy and the postpartum period are times of markedly increased risk of clot formation and, therefore, women who require anticoagulation should be fully anticoagulated throughout this time. I am currently on a beta-blocker. Can I take this medication while I am pregnant?
Many women with Marfan syndrome, especially those who have moderate or marked aortic dilatation for age, are treated with beta-blockers to attempt to lower the risk of aortic enlargement and dissection. Beta-blockers can be continued throughout the pregnancy, including the first trimester.
There have been some studies that showed a lower birth weight in infants exposed to beta-blockers during pregnancy. This happened most often with atenolol (Tenormin), a commonly used beta-blocker for people with Marfan syndrome. In addition, two beta-blockers -- atenolol and propranolol -- have been associated with minor heart problems immediately after birth, but they correct themselves within two days after birth.
Babies who have been exposed to beta-blockers should be closely watched after they are born. This can be done in the traditional nursery setting for an otherwise healthy infant. Just make sure that your pediatrician is aware of the mother’s use of beta-blockers. Should I expect any additional bone and joint problems during pregnancy?
Pregnancy often causes an increase in joint and bone pain, especially in the lower back, pelvis and legs. Walking around usually causes more pain; sitting and reclining lessen it. Occasionally, bed rest is required for parts of the pregnancy if sitting or reclining does not help. Is it safer for me to have a vaginal delivery of a c-section?
Research shows that women with Marfan syndrome who have an aortic diameter of less than 4.0 cm have similar outcomes with a vaginal delivery and a c-section.
Some recommendations to reduce risk include: - Use of an epidural to keep the blood pressure stable.
- Avoid bearing down or "pushing." Instead, forceps should be used to assist with the delivery once the cervix is dilated.
There is some controversy about whether vaginal delivery or c-section is safer for women with a larger aortic diameter. It may be less risky to deliver these women by c-section before they go into labor. Can I have an epidural?
Epidural anesthesia is safe for the vast majority of women with Marfan syndrome. However, it is not advised for women with moderately severe dural ectasia. Dural ectasia causes the dura to balloon out, leaving virtually no epidural space. The chances of a spinal fluid (CSF) leak would seem to be high. Are there special considerations for the baby at birth?
At birth, the pediatrician should conduct a basic examination, as would be done for any newborn. The only pressing issue is the presence of severe mitral regurgitation (the back flow of blood from the left ventricle to the left atrium of the heart through a defective mitral valve; also known as mitral incompetence). This is the most common cause of significant problems in infants, but more often seen in infants who are the first in the family to be affected with Marfan syndrome. Severe mitral regurgitation can be heard by a doctor with a stethoscope.
For the child – whether he or she inherited the disorder or is the first in the family affected -- an early evaluation of their eyes is important to be sure that their eyesight develops normally. Because lens dislocation may be present at birth or shortly after, a dilated eye exam is recommended. In general, comprehensive evaluation of the child by the pediatrician is important and should be done in conjunction with evaluation by a geneticist, cardiologist, ophthalmologist and other specialists, as needed. Links:for more detailed medical information on pregnancy see our Obstetric Concerns Brochure. For information on how Marfan syndrome is inherited, see an excerpt from our booklet Marfan syndrome and an article on Inheritance.
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