Brief Answer:
missed abortion....

Detailed Answer:
Hello,
Thanks for the query to HCM,
Missed miscarriages are fairly common in women and it is not related to 9th week per se. Th heart beat usually arrives by 6-7 weeks and if the foetus is not compatible to life due to possibly any congenital anomalies or any innate metabolic disorders then the heart may stop beating after starting once as nature decides on its own that this pregnancy is not compatible to life and hence its miscarried.
Another terminology is anembryonic gestation or blighted ovum where the heart beat never arrives till even 8th week and that also demands termination of pregnancy like this one.
The cause cannot usually be established as karyotyping , microarray and FISH studies are usually not possible on such a small embryo and even foetal tissue is inadequate for examination.
Again it is not necessary that first miscarriage will have an implication on next pregnancy as well, so you need to understand that.
Regards

---