I am almost eight weeks along in a twin pregnancy. Three weeks ago an ultrasound showed a spot in the uterus, but the babies were growing fine. A week later, another ultrasound showed one baby was weakening in growth, and we didn't hear heartbeats. Last week, the ultrasound showed both heartbeats had stopped. The spot is the same size, almost 20mm long (I think), but it seemed like it came too close to the embryos. I will have one more ultrasound to make sure, and then probably a D&C. The doctor thinks this may be a blood clot. Can that happen again? We got pregnant through fertility treatment.

S.

I'm sorry for your loss. It is always hard to lose a wanted pregnancy, and doubly so when you have to work so hard to get pregnant in the first place.

What you describe could indeed be a blood clot from separation of the placenta. If too large an area of the placenta separates from the wall of the uterus, it cannot supply oxygen and nutrients in sufficient amounts to the fetus(es). The result will be miscarriage (early in pregnancy) or poor growth or stillbirth (later in pregnancy).

The risk of recurrence depends on many factors. For instance, if you have high blood pressure, it will be more likely to happen again than if your blood pressure is normal. In general, however, miscarriages are very common, occurring in 20 percent of recognized pregnancies, and they do not recur again and again. The odds are that you will have a happier outcome next time around.