16w0d - Neo ain't got nothin' on me!

You know the scene in The Matrix where Neo dodges the bullets? Well, he's not the only one with this skill. Heck, I even had a dream about dodging bullets a few months back. Apparently, it was more prophetic than I thought.

A bit of history first. This pregnancy resulted from a dodged IVF bullet. Then, we had the scare with The Bean's bladder, but turns out we dodged that one too. Now, I have a third (and hopefully last) bullet that we've dodged.

After my OB appointment last Friday, I got a call from my OB. He'd been going over my records that were transferred from the MW upstairs that I'd seen at 8wks. At that appointment, the MW had me do the basic OB bloodwork panel. In those test results my new OB saw that I had tested positive for the anti-Jk antibody. (Huh?) He wanted me to get some more blood drawn to double check and to measure the amount of antibodies in my blood. I was taking NSWO to swim class so I didn't have time to ask much more so I got straight to work researching this issue when I got home. What I found wasn't very good.

Bear with me, this is fairly complicated, but I'll try to explain as best as I can. Most people are aware of the Rh blood grouping system. Most people are positive for Rh (A+, AB+, O+, etc.) but some are Rh negative (A-, B-, O-). There is a protein on the red blood cell's surface that determines your Rh status. There are other proteins on the red blood cell as well and one of them is called Jk, from the Kidd group. About 15% of the population is Rh- and the number of people with blood that is Jk- is far smaller (maybe 1-2%). If the mother is Jk- and her partner is Jk+ there is a chance that the baby could be Jk+ as well. If the blood between mother and fetus mixes, the mother's body will see the presence of the protein as a foreign invader and develop antibodies to it. Most women who are Rh- get an injection called Rhogam to prevent these antibodies from being formed by her body. Unfortunately, there is no equivilant injection for people who are Jk-.

If the mother develops antibodies to the blood of her fetus, it is more likely to affect subsequent pregnancies if the next fetus is also Jk+. The antibodies she makes are small enough to pass thru the placenta to the baby and they start attacking the protein on the fetus' red blood cells causing them to explode. This causes anemia for the baby because it has too few red blood cells to carry oxygen to the body's cells. Depending on how much antibodies the mother is making it can have anywhere from no effect up to a severe effect on the fetus. If the level of antibodies gets too high, they have to monitor the baby for effects. The old way of doing this was repeated amnios every few weeks. Luckily, there is a better way that isn't nearly as invasive. Using doppler imaging with ultrasound they can measure how fast the blood is flowing thru the middle cerebral artery of the baby. If it's too fast, that means the blood is too thin so the heart is working harder to get the oxygen where it needs to go. If that happens, they will often need to perform an IUT (intra-uterine tranfusion - giving the baby new blood via the umbilical cord while in utero) of the baby to give it less anemic blood that the mother's body doesn't see as an invader (Jk- blood). Over time, the baby's bone marrow will replace the baby's blood and the mother's antibodies will attack again. IUTs may need to be repeated until the baby is big enough to be delivered early, often around 34 weeks gestation. (Full-term is 40 weeks). Sometimes, the baby will need another transfusion after birth and can suffer from HDN (hemolytic disease of the newborn) including severe jaundice as well as the other risks associated with premature delivery. These babies can spend weeks in the NICU trying to recover. Most do well, but it isn't an easy road for the pregnancy or the newborn.

So, after all that doom and gloom, back to my original point, we dodged another bullet. The lab results came back from Monday's blood draw and apparently there are no anti-Jk antibodies in that sample. Since the original test went to a different lab, there's a chance that it was lab error or perhaps there are so little of the antibodies in my blood that they are not showing up at this point. In any event, we have been cleared of this possible complication and couldn't be happier about that. Now, I'm just hoping that we don't need to dodge anything else, but at least I'm getting good at it.