Wednesday, July 28, 2010

Other News

After Monday's ultrasound, we also met with our doctor. The results of that meeting:

1. No more shots; Sunday's progesterone injection was the last shot for this cycle.
2. The other hormone supplements are to be stepped down over the next two weeks.
3. We go back for one more sonogram and meeting with Dr. Ke on Monday August 9th; this is expected to be the last trip to the fertility clinic in Memphis.
4. We're to be handed over to our local OB effective August 17th, when we have our first appointment with him.

So all is well, I think. Did I miss anything?

Monday's Ultrasound

We had another sonogram on Monday the 26th.  A picture, shot with my iPhone:


A marked-up version so you'll know what you're looking at:


Baby is still doing well; 1.34cm in length, with a heartbeat of 166bpm, and a very recognizable person-shape. (Here, picture a baby laying on his right side.) All signs are good.

Wednesday, July 21, 2010

One Baby

Last Thursday, we went and had an ultrasound to settle the critical "one baby or two" question.  Here is the result of that test:


Unhelpful, right?  Like a snowy TV, really.  Here. let me give you a hand:

The picture shows one baby (because that's what we're having: one baby).  Don't be tempted to think the little peanut-shaped bright structure (the yolk sac, labeled here) is the baby; it's not.  The baby is a darker mass up from and left of the yolk sac.  I know this because, from inside the room, you can see the baby's tiny heart beating right in that area. The heartbeat was good and strong --- a particular concenr of ours, given our personal history. 

For scale, I've labeled the gestational sac, which is 1.7cm in length.  The baby here is about 0.3cm in length --  the size of a small coffee bean.  For this reason Sarah briefly took to referring to baby as "Latte Hopkins."

Friday, July 2, 2010

Twinning

Because it's come up in a couple of Facebook comments, I want to say a word or two about the upper bound on the number of babies Sarah might be carrying. 

The short answer is: two.  The doc transferred two embryos.  If they've both survived, then Sarah's carrying twins; if only one has survived, then it's just one baby (for this time).

The longer answer is: well, it depends.  There were two blastocysts on Day 5.  Most identical twinning is thought to happen at the blastocyst stage between Days 4 and 8. The astute reader will note that 5 is more than 4 but less than 8; this means it is at least possible for a day Day 5 blast to split into monozygotic (identical) twins after the transfer.  So it's possible, in the strictest sense of the word, that Sarah's carrying quads, in the form of two sets of identical twins.

Setting aside what is and isn't possible, the likelihood of Sarah carrying one, two, or more babies is subject to the usual rules of probability.  On transfer day, Dr. Kutteh told us that the probabilities broke down by thirds: one-third of women in Sarah's situation would have twins; one third would get a single pregnancy; and one third would get no pregnancy.  Two weeks on, we know we're not in the "no pregnancy" group.  So there's a ~50% chance that we're in the singleton group, and a ~50% chance we're in the dizygotic twins group.

Beyond that, probabilities get small. Identical twins account for about 3 of every 1000 pregnancies.  That's 0.3%.  So the probabilities break down like this:

49.85% one baby
49.85% fraternal twins
0.15% identical twins
0.15% triplets, composed of 1 set of identical twins and a fraternal triplet.

The probability of quads of any kind is too small to register at this number of sig figs.  And of course the identical twinning numbers here are too big: some identicals form between days 1 and 5, and we know that didn't happen.  But this is a good rough guide to the possibility of tour taking home more than two babies this go-round. 

The take home message is: because identical twinning is always rare the odds are slim; but because identical twinning does happen and can't be ruled out on the basis of the transfer day, the odds are not zero


Follow-On Test Result

The other day I mentioned that we got a positive pregnancy test.  I believe (this technical details are not 100% certain) that the test was a quantitative assay for hCG, and that the numerical result was 120.07 mIU/mL.  Following this result we were instructed to come back in for a follow-on test today.  The doctors were hoping to see an 80-100% increase in this level in the 48 hours between tests.  This near-doubling would nail down the "is she pregnant?" question for sure and certain.

(In addition, this rate of change is commonly used to check for ectopic pregnancy.  In our case an ectopic pregnancy is very unlikely; 98% of ectopics occur in the fallopian tubes, which Sarah doesn't have.)

As you might imagine, this post exists to report the result of the follow on test.  Drawn this morning, Sarah's blood contains 383.75 mIU/mL hCG.  (Again, the unit is somewhat uncertain, but the number is right.)  That's well more than a doubling; in fact it's slightly more than a tripling in 48 hours (an increase of 220%, to be precise).

Now, I know your next question, and the answer is: yes, high [hCG] levels and a high rate of increase in [hCG] can indeed suggest the presence of twins.  That said, as an indicator this is highly imperfect.  The basic problem appears to be that individual variance is very high, so even very wide divergence from the 48hr doubling may simply be individual "noise" rather than a twinning "signal".  That said, these test results are definitely adding dramatic tension to the time from now until the ultrasound on the 15th.