Q. When a couple marries, they must separate from each other as if she were a menstruate after their first experienced marital relations. Is this true only if she was a virgin or regardless of her physical status?
How about in the case of a virgin bride who is elderly and past menopause?
A. Shulchan Aruch (E. H. 193: 1) based on Talmud (Nida 65b) rules that the one that weds a virgin performs the mitzva of having relations with her and then separates. Since we are concerned that the blood experienced may be a nida or menstrual discharge.
The above applies as it is mentioned, only in the case of a virgin.
If the virgin bride is elderly and past menopause, Horav Shlomo Miller's Shlit'a opinion is that the law of separation still applies. The Rov explained that if it applies to a ketana (see Shulchan Aruch ibid.), it definitely applies to our case.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit'a