[Periodic abstinence: its possibilities].
D003267:Contraception; D003268:Contraception Behavior; D005193:Family Planning Services; D010061:Ovulation Detection; D012746:Sexual Abstinence
Cervical Mucus Method; Contraception; Contraception Failure--statistics; Contraceptive Usage; Family Planning; Family Planning, Behavioral Methods; Natural Family Planning; Sexual Abstinence; Sympto-thermal Method