Patient Selection and Safety With TNF Inhibitors - Episode 26
Recommendations for evaluating and working with patients who have an autoimmune disease to establish a care plan during pregnancy.
Christopher Robinson, MD, MSCR, FACOG: When evaluating an individual who comes in to see us with autoimmune disease, it’s important to focus not just on the disease but also on the entire person. In other words, it’s important to take that disease and place it as part of their care plan, but it’s also important to plan how to minimize the impacts of that disease. There are 2 critical questions here. One is, does my disease state affect the development of my baby? And the second is, does my being pregnant affect the course of my disease over the long term? Those are both interesting questions that are important to answer.
When we look at whether the patient’s disease state affects her pregnancy, we evaluate things like the renal function of the patient. Usually, we evaluate the kidney function. Usually this is a protein-creatinine ratio or a 24-hour urine to evaluate total proteinuria. We know that women who have an autoimmune disease are at increased risk for hypertensive disease in pregnancy—1 specifically called preeclampsia. And so getting baseline information about some of these factors is very important in our helping to manage that patient and understand what her pregnancy course looks like later on in pregnancy.
We also look very early at things like supplementation with folate. Folic acid is very important at preventing certain birth defects. For instance, spine defects, or spina bifida, which is a very disabling condition, can be prevented in up to 70% of cases with appropriate folate supplementation. Some women with autoimmune disease, especially those who have Crohn disease or ulcerative colitis, may have impaired ability to absorb those agents. And so we actually double the amount of folate that’s recommended from 1 to 2 mg in those pregnancies to help reduce that risk.
We also look at things like the baseline health state of this woman. For instance, is she iron deficient as a result of her disease where she’s not absorbing iron normally? Inflammatory disease states, such as those found in autoimmune disease, often result in iron-deficiency anemia above and beyond what we see in the healthy population. More complicated to that is, even with supplementation orally, they may not absorb it well. So we may even discuss things like IV [intravenous] iron supplementation to ensure that the mother has adequate iron. A healthy pregnancy requires approximately 1.5 to 2 g of iron. If you think about that, if paper clips were made of iron, we’re talking about 3 or 4 paper clips. That’s supporting not only the baby but also the placenta and the blood that the baby need to develop over time. The fortunate thing is the baby will generally always receive that, but the mother will be deficient as a result of that. So we look at that.
We also talk about nutrition. One of the key features in autoimmune disease is sometimes patients cannot gain weight like normal patients would in pregnancy. There needs to be a focus not only on the amount. A lot of people focus on how much they should eat. Rather, what is the quality of what they eat? Looking at those quality choices and how to get to nutrition, how to get to the appropriate caloric increase across pregnancy, can help reduce things like problems with growth of the baby later on in pregnancy and also reduce the likelihood of an early delivery as a result of those complications.
We also turn ourselves to the disease state itself. Fortunately, autoimmune disease, in many cases, will improve in pregnancy, though it does not go away. That is an important aspect. Up to half of women may still experience signs and symptoms of a degree of autoimmune disease activity in pregnancy. Pregnancy is 1 of the only times in your life that you are carrying an individual inside your body that is not directly of yourself. And so it’s almost like a transplant. Many people have thought, “Well, why is it my baby would not be rejected by my immune system? If I received an artificial heart or kidney transplant, they would put me on a lot of medications to prevent that from happening.” The baby and specifically the placenta have developed some very unique molecular mechanisms to hide from the immune system. One of those aspects is really the turning down of the Th1 [type 1 helper] immunity, which is the immunity that’s responsible for T-cell mediated immunity, reducing the ability for that type of immunity from reacting with the pregnancy itself.
Now, of course that comes with other concerns. When we look at viruses, certain viruses in our environment can cause problems with babies, but they never would have caused a problem if you weren’t pregnant. That’s because that immune system is turned off. Because that is turned off, that also assists in the autoimmune disease activity state when you look at that across pregnancy. So that’s important.
It’s also important to have a plan for maintaining remission. In other words, our goal was to get a person into remission prior to coming into pregnancy. It may have required a change in medication, then still having a period of remission. We don’t want to turn everything off when pregnancy occurs. The key is, we want to maintain remission. And so, the purpose is really to evaluate how to maintain remission. And then, who are the different people who need to be at the table in making decisions?
One thing patients like to have is a group of physicians who are talking to one another, who have interactive discussions about how they are going to take care of the patient. This can involve gastroenterologists, maternal-fetal medicine specialists, an OB-GYN, a nutritionist. It may also involve other individuals, as needed, such as after-delivery lactation support. It may involve a surgeon. If a person has had a complex surgical history where they may need assistance in timing of delivery and, specifically, access to the baby at time of C-section [cesarean], that may also be necessary.
Then there needs to be follow-up throughout the pregnancy. From the maternal-fetal medicine specialist side, we’re going to evaluate certain parameters to tell us how the pregnancy is progressing from the fetal state. One of those key features is, how is the baby growing? We talked about inflammation in autoimmune disease. Inflammation can create the risk of preterm birth. As a result, we usually evaluate the cervix of the patient to look for evidence of a short cervix, which can be a precursor of a preterm birth. There are some things we can do about that if that were to exist.
We also follow that baby month by month, to look at growth. We monitor the mom’s nutrition across that time, looking at weight gain, looking at her blood pressure, monitoring how she is doing, sometimes checking blood counts, also checking some of those micronutrient counts such as B12 and iron levels, then continuing that prenatal vitamin across pregnancy and folic acid supplementation.
So we go through pregnancy. When we are close to term, we usually begin to monitor the baby on a weekly basis to ensure that the baby is doing well in utero—receiving adequate oxygen, activity, and those sort of things. And then we move toward the decision of timing of delivery. We begin to think about how the baby should be delivered. For instance, should the patient have a cesarean delivery or a vaginal delivery? In the majority of cases with autoimmune disease, a vaginal delivery should be planned. But if a person has a disease state in which the perineum is involved in active disease, the patient should be considered for cesarean. There may be other patients who have had complex, previous GI surgeries, where they have conduits that could be affected by having vaginal delivery. Those individuals may also plan to have a cesarean delivery. When that takes place, when we make those decisions, we then create timelines for that occurring. We try to get all these women to term. The goal is certainly to get to 39 weeks, completed gestation, and then have a healthy baby as a result of that.