Maternal floor infarction

On Thursday, Oct. 15, my doctor called with the results of my clotting disorder tests and Luke’s autopsy (clotting disorders such as a Factor V or Factor II mutation are one cause of stillbirths).

First, she said, all my labs came back normal except one. I have the xx mutation of the MTHFR gene, involved in metabolizing folic acid. It’s a common mutation, she said: “80 percent of the female population has it.” I would need to take baby aspirin throughout a subsequent pregnancy.

Next, the autopsy. “The baby was fine,” she said. “There was nothing wrong with him. It was the placenta.”

The cause, she continued, was determined to be an extremely rare placental disorder known as maternal floor infarction (MFI). (The condition may also be known as massive perivillous fibrin deposition, or MPFD, although at least one journal abstract I found seems to suggest that they are different conditions on a spectrum.) In any case, what happened was that a clot formed, resulting in placenta insufficiency: a placenta unable to sustain Luke. In the scientific language, fibrin (a clotting protein) built up in the spaces between the placental villi, the small fingerlike projections that we all learned about in health class. The placenta was actually 75 percent “infarcted.”

From the autopsy report: Massive perivillous fibrin deposition is a condition characterized by enmeshment of chorionic villi in a fibrinoid material and in placental insufficiency of various degrees. The perivillous fibrin deposition essentially strangles the chorionic villi. This in turn leads to a marked reduction of fetal blood flow in the affected villi and secondary stromal fibrosis. Thus, functional villi are reduced in number, and if the process is sufficiently large, placental function is compromised. The consequences include a significant risk of intrauterine growth restriction, intrauterine death, and preterm delivery.

“We do not know what causes it,” my doctor said, “and the downside is that it has a high risk of recurrence.” Around 30-32 weeks of a subsequent pregnancy, she said, I would be monitored more closely, with twice-weekly ultrasounds, and would be induced at 37 weeks (which was the plan anyway, before we knew the cause). “The ultrasound can show some things, but not everything,” she said; I would also have to be hyper-vigilant about kick counts, but in the end, we would have to leave things up to a certain amount of chance.

I reeled from shock. I had always figured the autopsy would come back inconclusive, or with some kind of freak cord accident. I knew the chance of having two stillbirths was incredibly rare, much more rare than the risk of having one (I think it’s like 2 percent of all stillbirth moms go on to have a second stillbirth), and it never occurred to me that a subsequent pregnancy would really, truly be high risk and that my rainbow baby could be just a fleeting dream. Suddenly I was launched into the grieving process all over again, and now trying to figure out how we could decide whether to try to have another child.

After digesting this information for a few days, I contacted the Star Legacy Foundation for Stillbirth Awareness. In online searches for both maternal floor infarction and massive perivillous fibrin deposition, I had found mostly technical journal abstracts, nothing much written from the lay perspective or by other mothers in the same situation. I asked the foundation if they had any information on the condition(s) written for a lay audience. To my surprise and eternal gratitude, they responded within hours and forwarded my inquiry to two members of their board.

The first, placental pathologist Dr. Mana Parast of the University of California, responded with a recommendation that I be screened for autoimmune conditions such as lupus and antiphospholipid antibody syndrome (a clotting disorder). She said if an autoimmune condition is indicated, she has known women treated with low molecular weight heparin or other treatments during subsequent pregnancies who delivered healthy babies (and normal-looking placentas).

Then she mentioned that she might question whether the cause was MFI, and not instead a condition that can mimic MFI called villitis of unknown etiology (VUE), in which the mother’s immune system attacks paternal antigens on placental cells. It can also be associated with fibrin deposition in the placenta. The recurrence rate is high, just as for MFI (up to 50 percent in subsequent pregnancies), but there is no treatment.

Since I had a normal pregnancy with Zoe, she questions the MFI diagnosis, unless Zoe had undetected fetal growth restriction or I developed an autoimmune disease after that pregnancy. On the other hand, VUE, she noted, gets worse with subsequent pregnancies (i.e., “mom’s immune system is now alerted to the paternal antigens, so she’ll fight them back faster”).

We are in the process of sending samples of my placenta to a Yale pathologist, Dr. Harvey Kliman, also recommended by the Star Legacy Foundation. Hopefully Dr. Kliman will be able to give us a definitive answer as to MFI/MPFD or VUE, and we can go from there.

Star Legacy also connected me with Dr. Alexander Heazell of the UK’s University of Manchester, who has created “rainbow clinics” to work closely with parents to plan and deliver subsequent pregnancies. Dr. Heazell was in a radiology residency program when his child was stillborn, and he changed his focus to OB/GYN, dedicating his career to finding answers. He didn’t have much to add to what I already knew, but it gave me hope to hear that his clinics have yet to lose a rainbow pregnancy.

In the meantime, I have a number of questions swirling around my head—ones I can’t seem to find many answers to because a) I don’t want to shell out hundreds of bucks for a journal subscription, and b) the disorder is so rare and so poorly understood that there aren’t many journal articles on it to begin with. Among my questions:

1. MFI is associated with central nervous system (CNS) injuries and “adverse neurodevelopment outcomes” such as cerebral palsy. What impact does treatment (aspirin, heparin) have on the risk of such outcomes?
2. Is VUE also associated with such outcomes?
3. Are MFI and MPFD truly on a spectrum? What does that mean for my situation? Where am I on the spectrum?
4. In the case of MFI, does treatment eliminate or merely reduce the risk of another stillbirth?
5. What exactly is the risk of recurrence with MFI?
6. Does my MTHFR mutation have anything to do with MFI? I’ve seen other women with MFI say they were prescribed extra folic acid (not sure if they meant folate) in subsequent pregnancies; is this because the MTHFR mutation is somehow related?
7. Is MFI/MPFD related to a clotting disorder, an autoimmune disorder, or both?
8. I’ve heard that some women develop clotting disorders only in pregnancy—so even if I came back negative for Factor V now, maybe I would have it during pregnancy?
9. Exactly which autoimmune diseases should I be screened for?
10. Why the fuck is this happening to me?

Thanks to the kind folks at Star Legacy, I have some of these questions out to the placental pathologists and hope to hear more answers soon—and hopefully Dr. Kliman will also be able to clear a lot of this up for us. All I can do now is focus on the next step.