Anyone know about momo twins?

Ashley • TTC #2 after a twin miscarriage Eric born 5/12/14 twins lost 10/8/17

earlier this week i posted because they said they didn't find anything on my ultrasound. today I'm posting because it turns out they did. they found a single gestational sac with two fetal poles measuring 5weeks 3 days and 6weeks 0 days (as of Monday) but no heartbeat.

been doing a serious amount of research since i received this news on Wednesday. Twins in a single sac are momo twins (single sac-single placenta). also at the age they are measuring it isn't unusual not to see a heartbeat on the U/S.

I'm just extremely worried about my babies now. Even if everything is ok now there's a lot of complications with a momo twin pregnancy.