Are the secretions mixed with a spot of blood after marital foreplay and before penetration a result of the rupture of the hymen or for another reason, and must the husband be informed of that immediately?

If the شرعي (Shari'i) contract has been concluded, the woman becomes a wife, and it becomes permissible for them to enjoy each other. However, it is advisable to postpone sexual intercourse to respect common customs, and because the Shari'a has attached some rulings to the contract and others to consummation. Hastening sexual intercourse may lead to harms, such as the wife becoming pregnant before the expected consummation, which would put her in an embarrassing situation. The blood the questioner saw might be due to the hymen or not, and it is better for her to inform the husband about it to avoid future misunderstanding.