Use condoms to help protect you against STIs when you have penetrative anal sex. Use a water-based lubricant, which is available from pharmacies. Oil-based lubricants (such as lotion and moisturiser) can cause latex condoms to break or fail. Get tips on using condoms properly. Male and female couples should use a new condom if they have vaginal sex straight after anal sex. This is to avoid transferring bacteria from the anus to the vagina, which may lead to a urinary infection.