21mm gestational sac, yolk sac but no fetal pole. Any hope or am I preparing for the worst?

Throwaway, first pregnancy, 30, UK.
Looking for honest experiences, not just reassurance.
Had a transvaginal scan today due to some spotting. Results:
Single gestational sac, MSD 21.67mm
Yolk sac present
No embryo/fetal pole seen
Both ovaries normal, no free fluid

For anyone who had a sac this size with only a yolk sac and no pole at a similar dating - could you share what happened at your follow-up? Trying to brace myself honestly while the rest of me is still hoping.