This question follows from: What are “the tokens of virginity”?
Are there any Jewish groups then and now that check for a woman's virginity say by laying out a garment when marriage is first consummated? [cf. Deut 22:17].
From what I understand in parts of Judea originally (see source below) the friend of the groom and the friend of the bride together checked the sheet.
No bleeding does not mean not a virgin unless we double checked she was not virgin even if she was never with a man but was hit with a stick (i.e. is missing her Hyman for a different reason. If she was hit with a stick her kesuba is the same an a non-virgin).
The virginity check only helps the husband to lower the amount of the kesuba, or to nullify the wedding, if she admits that she was with another man.
If I remember correctly in the Talmud it stated the possibility that the blood is blocked by semen
Now (from what I see) usually only the husband checks (if he wants to), and we trust him (she can curse anyone that is lying regarding her (see end of previous link). Since he pays for the meal he would not want to ruin his wife (Helkas Mechokek 2 and Bais Shmuel 2) .