24 Jul Alport syndrome and Pregnancy
Pregnant women with Alport syndrome should be monitored closely and partner with their Nephrology and OB/GYN doctors for the best care during their pregnancy. ASF asked Dr. Michelle Rheault, Co-Director of the Alport syndrome Treatments and Outcomes Registry (ASTOR), to address some common concerns for pregnant women with Alport syndrome.
What do we know about the risks of pregnancy for women with Alport syndrome?
Very little is known about the risk of pregnancy in women with Alport syndrome, with only 10 pregnancies in 9 patients reported in the medical literature. Of course, we all know women with Alport syndrome who have had normal, healthy pregnancies, but these are not likely to get written about, so reports are skewed toward those with worse outcomes. In most reports, complications for the mother have included worsening protein in the urine (proteinuria), increased creatinine, high blood pressure, and preeclampsia. In women whose proteinuria increased during pregnancy, there was most often a return to pre-pregnancy levels after delivery. Some women have been reported to have worsening kidney function that did not improve after pregnancy. Research studies are needed to better define the risk of pregnancy for women with Alport syndrome. Women with Alport syndrome should talk to their nephrologist prior to pregnancy to discuss individual risks as these will vary depending on age, chronic kidney disease stage, urine protein levels, baseline blood pressure, weight, and other factors.
Preeclampsia refers to the new onset of high blood pressure, often with protein in the urine and edema (fluid retention and puffiness) that begins after 20 weeks of pregnancy (~ 4 ½ months). Some women with preeclampsia develop seizures and this is called “eclampsia”. High blood pressure and proteinuria due to preeclampsia should go back to normal after delivery, however this may take weeks to months. The treatment for preeclampsia is delivery of the baby, which can lead to complications of prematurity if this is required before 37 weeks gestation. Women with Alport syndrome may already have high blood pressure or proteinuria before pregnancy. If they develop worsening high blood pressure and proteinuria, this is called “superimposed preeclampsia”. Not all high blood pressure during pregnancy is due to preeclampsia. Women can also have “gestational hypertension” which is blood pressure that is newly elevated during pregnancy without proteinuria or other signs of preeclampsia that goes away after delivery. They may also have “chronic hypertension” which is blood pressure that was elevated before the pregnancy started and continues throughout the pregnancy.
What about risks of pregnancy for women with chronic kidney disease in general?
Chronic kidney disease from any cause is a risk factor for worse pregnancy outcomes, with increased risk for both the mother and baby. A recent review showed that the risk of gestational hypertension, preeclampsia, and eclampsia was about 5 times higher in women with chronic kidney disease than those with normal kidney function. Preeclampsia complicates about 25% of pregnancies in women who have chronic kidney disease or hypertension prior to pregnancy, with up to 40-60% of women with advanced chronic kidney disease (CKD stages 3, 4, and 5) developing preeclampsia. There is also a two-fold increased risk of adverse outcomes for the baby including premature birth, low birth weight, and poor fetal growth. Healthy pregnancies are certainly possible in women with chronic kidney disease, even those on dialysis or after kidney transplantation, however very close monitoring by doctors for both the mother and baby are required.
Can ACE inhibitors harm my baby?
Many women with Alport syndrome are on angiotensin converting enzyme inhibitors (ACE-I: enalapril, lisinopril, etc.) or angiotensin receptor blockers (ARB: losartan, etc) to treat high blood pressure or reduce protein in the urine. If these medications are taken early in pregnancy, even before a woman knows they are pregnant, they can cause severe birth defects including permanent kidney failure in the infant. If a woman is taking these medications, they should use reliable birth control so that they do not get pregnant. When they are ready to start a family, they should talk to their nephrologist about stopping the ACE or ARB prior to conception.
Will my baby have Alport syndrome?
A genetic counselor can help you determine your risk for passing on Alport syndrome to your children. The risk will depend on what type of mutation you have and what your inheritance pattern is (X-linked vs. autosomal recessive vs. autosomal dominant).