During my second pregnancy I received a phone call from my obstetrician after routine blood tests during my first trimester. He said that I had a positive antibody titer and that I would need more blood tests to find out exactly which antibody I had. He went on to explain that the antibodies in my blood, that were not present during my first pregnancy, probably came from my firstborn’s blood mixing with mine during delivery. Apparently my husband passed on a blood component that was normal in him, but was “foreign” to my body, onto my son, who in turn made my body think that it should build a defense against this component in case it should ever encounter this strange being again.
Now that I was pregnant again, those antibodies could eventually recognize this foreign blood in the baby that I was carrying, and attack. The antibodies attack the red blood cells and can cause severe anemia and then multi-organ failure in the baby. The good news was that if the baby could be born without my antibodies attacking then there was no further risk to the child.
I went into research mode, only to find out very little about blood antibodies and treatment during pregnancy. I did find out that the anemia associated with these antibodies is the same thing that can happen with Rh incompatibility. There is a treatment for this problem, but my antibodies were different and there was no treatment.
My doctor instructed me to see a perinatologist, an expert in high risk pregnancies. He told me that since the medical profession had eliminated the Rh problem by giving mothers who were Rh negative a shot called rhogam, that they were seeing an increase in different antibody anemias. He also laid out the tests I would need to go through over the next six months.
We started with more blood tests. As it turned out, I not only had one kind of antibody, I had two different ones. My husband was tested also, and he tested positive for both of the antigens. An antigen is a substance that prompts the generation of antibodies and can cause an immune response. These antigens were a perfectly normal genetic compound in his blood. The two antigens were called Kell and Kidd. I assumed they were named after the researchers who had discovered them.
The next step was ultrasounds at least every two weeks. The doctors were monitoring blood flow through the baby’s middle cerebral artery. This artery is located in the brain. If the timing of the blood flow sped up at any point during the pregnancy that was indicative of my antibodies attacking the baby’s red blood cells. If that would have happened then there were only two solutions: deliver the baby or, if the baby was too premature, perform an intrauterine blood transfusion. The blood transfusion would have to be given directly into the umbilical cord through the uterus.
With each appointment the doctor asked me if I wanted to know the sex of the baby. I caved at only the second ultrasound. I couldn’t say no more than once and was told that “it” was officially a boy.
He then suggested an amniocentesis to determine if this baby had the antigens. If the baby tested negative, then there was nothing to worry about. My antibodies would have nothing to attack. As it turned out, he only carried one of the antigens. This did reduce the risk to him, but didn’t eliminate it.
Other than the inconvenience of multiple doctors’ appointments, the pregnancy seemed perfectly normal. We were told that with each pregnancy the risks increase. Apparently the antibodies get smarter and react quicker when they face the same antigens over and over again. We were told that if we wanted to have anymore children then we should use a sperm donor. It did not take us long to decide that I would have a tubal ligation performed at the time of my c-section.
By my third trimester I had to have ultrasounds every week. The longer the pregnancy went on, the greater the chance that my antibodies would recognize the foreign blood and attack it. My doctor also performed weekly non-stress tests. He would monitor both the baby’s heart rate and uterine activity to see how the baby would react to contractions. If his heart rate dropped then they would consider delivering early.
At my thirty-seven week ultrasound my perinatologist said that our son would be born by the end of week. He felt that we were pushing our luck and didn’t want to risk letting the pregnancy go the full forty weeks. He contacted my obstetrician and scheduled a c-section for Friday morning.Our son was born a healthy 6 pounds, 9 ounces. His blood did contain a low antibody amount. Those antibodies had just begun to recognize his “foreign” blood. Luckily, his body was able to clear the antibodies on its own. He had a mild case of jaundice because of this, but other than that, he’s had absolutely no problems at all.
