|at 33 weeks and 6 days|
|at 33 weeks and 6 days|
I've been wanting to write about this for a little while now, but I couldn't find the right words. It's hard to write about something that you don't know enough about, and yet, because I'm living through it now, and have had to live through it in my previous pregnancy, I know a little more about it than the people who have just learned that this is something they will be facing in their pregnancy. And I know a little more about it than most of my friends and loved ones who have been praying for me and supporting me through the past several weeks. I have written about it in bits and pieces over most of my other pregnancy posts, so you can always browse through those as well.
The anti-little c antibody is part of the Rh complex. Most people know about the "D" antigen and know if they are Rh (D) positive or negative, if they know what blood type they are. What most of us don't know is that there are four other antigens that are part of this complex: "C", "c", "E", and "e". And this is actually ok, because encountering incompatibilities with these other antigens is actually quite rare. Also, these other antigens don't usually affect the babies as much as "D". Little "c" is one, however, that can cause hyperbilirubinemia (high levels of bilirubin and jaundice) and can cause anemia in the fetus and newborn, known as hemolytic disease of the fetus and newborn - HDF/N. Antibodies from the mother's blood cross the placenta and begin to attack and break down the baby's red blood cells.
When antibodies are detected in a pregnant women's blood during her labwork, she and her baby need to be monitored throughout the pregnancy, especially if the father's bloodwork shows that he has the antigen in question. (In our case, all of Dave's children will have the little "c" antigen.) In my experience, this has initially been through monthly bloodwork, where they measure the antibody titers. The longer the mother is exposed to the antigen, the more antibodies are produced and the higher the titers go.The ratio for "D" is fairly well established at 1:16 and this ratio tends to be used for most other antibodies, even though these haven't been established.
In October, my titers reached this critical level and I was referred to a perinatologist for further monitoring. My first appointment with them, however, was not until November 22. Dave and I had known that the antibodies were going to be an issue during this pregnancy. When we had Titus, he did not develop anemia, but his bilirubin levels were quite out of control and he ended up back in the hospital for a few days. Knowing that this baby would need special care after birth, we had always planned to travel to the Calgary area when it was time to have access to the care needed. What we did not expect was how soon that specialized care would need to come. In the last three weeks, our lives have been turned inside out and upside down while the boys and I have moved into my parents' home and I've been juggling multiple appointments every week. It is hard to be separated during this time.
The primary way the our baby is currently being monitored is through ultrasound and doppler technology, using a technique know as middle cerebral artery peak systolic velocity or MCA-PSV. They convert the raw numbers of peak velocity into multiples of a median (MoM) to account for differences in gestational age. I have had this done five times in the past three weeks. Each time the numbers have been creeping up, getting closer and closer to the 1.50 MoMs that they do not want to see. The understanding is that the higher the velocity through the cerebral artery, the more likely it is that the baby has developed anemia, especially the closer you get to 1.50 MoMs.
The treatment for anemia in the fetus is different depending on how far along in the pregnancy you are and the severity of the case. Here in Calgary, the threshold is 34 weeks. If the baby shows definite signs of anemia before 34 weeks, they will perform an intrauterine blood transfusion, where they replace some of the baby's blood with blood that is compatible with the mother's blood type. If this occurs after 34 weeks, they will deliver the baby prior to performing a blood transfusion. Even if the baby does not develop anemia, the antibodies can still cause high levels of bilirubin and jaundice that require intense intervention through the administration of IVIg and phototherapy. I've been told that IVIg works both to coat the red blood cells and prevent further breakdown, as well as to remove the antibodies from the system. However it works, it is what brought Titus' bilirubin under control after be was born.
This past week, I reached and passed the 34 week threshold. And I am very relieved over that. I really did not want my baby to have a blood transfusion before even being born. But the MCA values also seemed to be reaching critical levels. I have been very blessed with a perinatologist that listens to my concerns and takes careful consideration of my concerns as well as the factors affecting the baby. She does not want to see the levels reach or go above 1.50 MoM, and neither do Dave and I. We don't want this baby to develop anemia. So this week, she sent me to get two doses of a steriod shot to develop the baby's lungs, as well as arranged an extra ultrasound to double check the MCA values. Those values from the extra ultrasound were pretty shocking to me. They were the lowest numbers that I had seen in any of the ultrasounds. I can only say that I think they must have been "God numbers" because they were so vastly different from the others. And I know that there are many people praying that I "make it one more week" from my ultrasound last Tuesday.
Right now, I'm living in a tough spot of uncertainty. The numbers from Thursday's ultrasound make me wonder if I'm crazy to think that this baby is going to be born so early. And yet, the numbers from the ultrasound from Tuesday make me antsy to "get this baby out" to minimize how much longer she will be exposed to the antibodies. Whether she has anemia or not, she will still have a struggle ahead of her and will need to be treated aggressively to prevent her bilirubin levels to get out of hand. In addition to my worries, I've been struggling with a lot of extra pain and sleeplessness this week. I have finally realized that some of these physical symptoms, especially the sleeplessness, are linked to the steriod shots that I had. My worst night of sleep was after my second dose. This weekend, I hit a wall and my body has been letting me know that it doesn't like how it has been treated lately. I've spent most of today resting and trying to regain some sense of well-being. I'm really hoping that tomorrow will be better.
So, what is best for baby? And how on earth do you prepare for having the baby when your family is separated by hundreds of miles and you don't know how urgently that baby will need to be delivered? Right now, we're operating under the assumption that the baby will be born this week and Dave is coming to join us here. We're also hoping and praying that by Christmastime, we'll be able to bring our baby home and be together as a family. I am a little sad as I contemplate the birth. The boys are both so excited to be getting a little sister, but when will they get to meet her? Probably not until she is discharged. This time, wondering when the baby will be born is harder than it ever was with the boys, because I also am so worried about my baby's health.
For further reading:
- Middle cerebral artery peak systolic velocity for the diagnosis of fetal anemia: the untold story
- Antibody titer testing on pregnant women when the patient has an antibody known to possibly cause hemolytic disease of the newborn/fetus (HDN/F)