At 10 weeks of pregnancy, which is approximately two and a half months along, you are nearing the end of the first trimester. By this time, an ultrasound should definitely be able to detect a fetal heartbeat. If no heartbeat is observed by the 9th week, it is typically diagnosed as a missed miscarriage. Therefore, if no heartbeat is detected at 10 weeks, it should also be diagnosed as a missed miscarriage. There are two possible scenarios when there is no fetal heartbeat at 10 weeks: 1. It’s possible that there was never a heartbeat, indicating that the gestational sac was of poor quality from the start. 2. A heartbeat might have been present initially but later disappeared, possibly due to external factors or chromosomal abnormalities in the gestational sac. In such cases, a comprehensive screening should be conducted to determine the cause of the missed miscarriage. This may include tests for chromosomal issues, immune system factors, rheumatological conditions, infections, and coagulation disorders. Identifying the underlying cause can help guide future pregnancies and reduce the risk of recurrent miscarriages.