Contraception

 Preventing ovulation ◦ Oral contraceptive ◦ Implant  Preventing fertilisation ◦ Barrier methods  Condom  Vaginal sponge  Cervical cap  Diaphragm Contraception  Preventing fertilisation ◦ Sterilisation  Vasectomy  Tubal ligation  Preventing implantation ◦ IUD ◦ Post-coital contraception

 Chastity belt  Very effective (but probably very painful) - provided no-one else has a key!

Have sex and …  Prevent the production of ova or sperm  Prevent fertilisation of the ovum  Prevent implantation Don’t have sex …  Abstinence

 Oestrogen-based pills send false messages to the brain and prevent ovulation.  Progesterone-based pills cause a mucus plug to form in the cervix, thus preventing sperm entering the uterus.

Oral contraceptive  “The Pill”  Mostly contain a combination of oestrogen and progesterone  Every fourth week, a placebo is taken and the woman will have her period

Implanon  Progesterone only  Implanted under the skin, diffusing a constant, regulated level of hormone  It lasts for up to 3 years

Male sterilisation - vasectomy  In males the vas deferens can be cut, thus preventing sperm leaving the testes.  Sperm production continues but the sperm are broken down and are reabsorbed by the body.  After a vasectomy men can still ejaculate (seminal fluid only) and continue to produce testosterone (it does not affect their sex drive).  In some cases a vasectomy can be reversed.

Female sterilisation - Tubal ligation  In females the Fallopian tubes are cut or sealed, thus preventing fertilisation.  Ovulation and menstruation continue after the operation and sex drive is not affected.  In some cases a tubal ligation is reversible.

Coitus interruptus  The man withdraws before ejaculating. Douching  Washing out the vagina after intercourse. Ovulation or rhythm method  A woman calculates her ‘safe’ period based on her body temperature and appearance of vaginal secretions. None of these methods should be regarded as reliable.

Condom Vaginal sponge 1 2 3

 These devices are moderately effective, especially if used in combination with a chemical barrier, such as a spermicide.  Only the male condom offers some protection against the transmission of STIs.

Intra-uterine device (IUD)  IUDs are small T-shaped plastic devices inserted into the uterus by a doctor.  Modern IUDs contain either copper or hormones which prevent fertilisation.  The IUD itself prevents implantation.  IUDs can be left in place from 5 to 10 years.

 The ‘morning after pill’ can be used in emergency situations up to 72 hours after intercourse if there is a risk of an unwanted pregnancy.  These drugs contain high levels of estrogen and/or progesterone which prevent implantation.  The so called ‘abortion pill’, RU-468 blocks the production of progesterone needed to sustain a pregnancy.

 What are the ethical considerations when using IUD’s and post-coital contraceptive methods?

Method% failure rate Chance of pregnancy Male & female sterilisation<1<1 in 100 Implanon<1<1 in 100 IUD<1<1 in 100 Oral contraceptive, combined pill81 in 13 Male condom151 in 7 Cervical cap / sponge + spermicide 15 (no children) 1 in 7 30 (children) 1 in 3 Natural ‘rhythm’ method251 in 4 Diaphragm + spermicide 301 in 3 Spermicide alone301 in 3 Birth control methods – failure rates Based on data from US Food and Drug Administration