Is this sign considered inappropriate to use in public?
The sign itself is a neutral, medical term. While the context of your conversation dictates its appropriateness, it is perfectly acceptable to use in educational, medical, or private settings.
Do I need to mouth the word 'condom' while signing?
Yes, it is helpful to mouth the word 'condom' to provide clear context. Because the sign uses a simple sliding motion, mouthing helps ensure it isn't confused with other classifier descriptions.
Can I use either hand as the base?
Typically, your non-dominant hand serves as the stationary base (the upright finger), while your dominant hand performs the sliding action. This follows standard ASL grammar rules for active and passive hands.