1d (6 letters). Could you get pregnant during a Viagra video
G?A?I?
21d (7 letters). Mangy creature in cap can't spread
??M?T?D (The T and D are correct so its not Lemming as suggested elsewhere).
21a (4 letters). Be persistent but not at first
??S?
20d (4 letters). With 2D or 23D, for example, loss in head area leads to minor religious entity. Note: Answer to clue 2D was Locust and 23D was Tsetse
S?C?