Contraception

Reversible sterilization –Controlled by the individual –Different methods Natural method Physical and chemical barriers Steroid analogues and antagonist

Natural methods Coital methods –No chemical/physical interventions Societal view of artificial interventions Religious view of artificial interventions –Rhythm method Avoiding coitus around the time of ovulation –First part of menstrual cycle –Based on menstrual cycle –Based on lifespan of oocyte and sperms

Natural methods Coital methods –Rhythm method Avoiding coitus around the time of ovulation –Variation in body temperature during ovulation ( C increase) Not as effective –Variation in the time of ovulation –20 X less effective compared to oral contraceptions

Natural methods Coital methods –Coitus interruption Withdraw of penis before ejaculation Most common form of contraception –Not highly effective –Mutual masturbation and oral sex No vaginal insemination –Reduced disease transmission

Physical and chemical barriers Condoms –Male Most common form of mechanical contraception –Female Protection of cervical os from coming in contact with semen after coitus

Diaphragm –Similar to condom Barrier between vagina and cervix –Use in combination with spermatocides –Control of fertility by females Protection against inflammatory diseases Needs training/practice for high efficiency

Oral contraceptives Chemical suppression of ovulation –Artificial steroid analogues Longer half-life Progesterone analogue with or without estrogens –Mimics pregnancy to some extend –Effectiveness Duration of exposure Types of steroids being used

Use of progesterone-estrogen combination –Progesterone alone Suppression of ovulation –Variable effectiveness –Addition of estrogens Additional feedback Increased progesterone effectiveness –Suppression of gonadotropin secretion 21 days plus 7 day break –Removal of old endometrium

Progesterone only contraceptives –Oral or injectable from Suppression of ovulation Abnormal ovarian activity Less side effects compared to combination contraceptives Higher chance on failure compared to combination –Strict regiments

Side effects –Social –Psychological –Physiological –Some potential for developing life- threatening conditions Blood clotting

Morning-after pill –High dose of estrogen Taken within 72 hours after the intercourse –Progesterone antagonist RU 486

Steroidal contraceptives for men Suppression of gonadotropin secretion –Progesterone –GnRH analogue –Results in reduced androgen production Reduced libido Reduced masculine stimulation –Use of androgen Health risks

Future Problems –Not technology User issues –Immunological approach Against hormones Against sperms