What the hell is a beta?
I heard this question a couple times after my last post, so we'll do some science education first!
When the embryo implants in the uterus, it starts secreting the "pregnancy" hormone, which is called human chorionic gonadotropin, or hCG. hCG will start small and continue to rise throughout pregnancy.
Home pregnancy tests are trying to detect hCG. Some have different sensititives than others. Perhaps one can detect it when it is at a level of 10 mlU/ml or above, some may be more like 50. But if you get a positive, you just know that it is above that range...you don't know the actual number.
The beta is the actual numerical measurement of that hormone. So, while we knew we had something in our system from the home pregnancy tests, we didn't know how much. This is normal for most natural pregnancies. Those folks would never get a blood test unless there were issues suspected. They would just wait for the first ob/gyn appointment (usually not for several more weeks), and plan to do an ultrasound at that time to detect the fetal heartbeat.
The good news for us is that we are not normal. We actually are technically normal now, as our "known" issue was getting pregnant, not staying pregnant (FINGERS CROSSED!). But the clinic treats all patients the same, so we get the similar special treatment as someone who needs more constant monitoring because of recurring miscarriages or something along those lines.
The actual acceptable range of hCG at any given point is pretty wide. You can go to several websites, and even the "min" and "max" and "average" they quote will be different. One of the medical sites indicates that for 17 dpo (which is the day that is equivalent to our first beta test a couple days ago), the range should be 60 to 429 with an average of 132. Well, I already know that is kind of b.s., because I know several people who have been outside that range (either above or below) and are perfectly fine. But we'll take our 274 and like it, because we are like being considered normal so far.
More important than the actual number is the rate of increase. Normally progressing betas should double every 30-72 hours while the level is below 1,200 mlU/ml. So our 274 on its own is somewhat meaningless in judging the viability of our pregnancy. We really want to take the beta test again and calculate the doubling time as well, which was the point of today's test. The doctor told us that he would be happy for at least 500 (doubling time of 55.32 hours). T and I were hoping for some more cushion than that, and were keeping our fingers crossed for at least 600 (42.45 hour doubling time). We were even taking the tests at the same time on each day to make the results really aligned.
We totally killed it! Beta #2 was 755. This equates to a doubling time of 32.82 hours! Yay!!!!!!
So now we start a period which may even be worse than the traditional two week waits of yore. We have nothing else upcoming except an ultrasound, which won't be for a couple weeks. Blech. I can't wait that long!!
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