I recently went in for my first ultrasound, I was guessed to be around 8 weeks 3 days. When the doctor began the ultrasound much to my surprise he said that it looked as though this started out as a twin pregnancy but one is a vanishing twin, he explained one sac clearly had a baby in it measuring 7 weeks 5 days with a detectable heartbeat while the other smaller sac next to it appeared to be empty. What are people’s experience with this and it turning out that the other twin just began developing after the first? The doctor was having a really hard time getting pictures due to positioning, I’m not getting my hopes too high but I have read some stories where the second sac does have a baby at the following ultrasound. I haven’t experienced any bleeding or unusual cramping