Yes: FC2 Female Condom® can be used with the pill, injections, IUD contraceptives, post-sterilization and post-vasectomy to protect against STIs, including HIV.
No: FC2 cannot be used with the diaphragm, cervical cap, sponge, or NuvaRing® as the inner ring of FC2 fits into the same place at the cervix.
Can these items be removed during sex and then reinserted? For example, can the birth control ring be removed just before sex, female condom placed, sex happens, female condom removed, birth control ring replaced? What am I asking is weather the contraindication is simply due to the placement, or is the hormones or something else released by the birth control ring which makes the female condom less effective?