Monoamniotic Vanishing Twin Syndrome

Has anyone had experience with monoamniotic vanishing twin syndrome?

At my first ultrasound at my IVF clinic last week at 7+2, the tech had a slightly hard time getting a good measurement of the baby but there was a great heartbeat and all looked well. I had my first ultrasound at my normal OB office yesterday at 8+2 and my nurse did an abdominal ultrasound. She couldn’t see a heartbeat so she had me do a vaginal ultrasound and the baby looked great with a really strong heartbeat. My nurse comes back in and says it seems like there are two babies in the same sac (mono mono) but one of them stopped growing at 7 weeks which is why we had such a hard time with the abdominal ultrasound. So in a nutshell, monoamniotic twins share the same placenta and sac whereas normal twins have their own. Just my luck, this is extremely rare and happens in less than 0.1% of all pregnancies.

Any similar stories with mono mono? I’m really sad that the one baby didn’t make it yet happy to have one that seems to be doing great. Really weird emotions with all of this because I know it would’ve been a really difficult pregnancy with both babies sharing the same sac 😕 Our first IVF cycle ended in a chemical miscarriage and then this cycle has the vanishing twin syndrome so I’m just super nervous as to what’s to come. I go back in for another ultrasound on Tuesday. Thank you for any responses.