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BIRTH CONTROL

To some, the term family planning is a euphemism for contraception, i.e. the prevention of pregnancy.
At its most basic level, it implies limiting reproduction. However, knowledge of the background to the reproduction process can be used in different contexts:
- to prevent unwanted pregnancy (with different degrees of reliability)
- to "spread out" children, for economic or other reasons
- to control the size of a family
- to ensure that no further children are produced (after a few ?)
- to maintain the health of a woman, if she may be adversely affected by pregnancy
- to maximise the chance of pregnancy
(10% of couples experience problems in having children, and about a third of those cannot be corrected).

FAMILY PLANNING METHODS

This flow chart indicates the stages in the human reproductive process, and the points at which intervention may prevent pregancy.
sperm + egg -> zygote, ball of cells, embryo, foetus, baby

- The rhythm method can be used either as a means of reducing the rate of increase in size of a family, or (in a different way!) as a way of increasing the chance of success of a childless couple who want to have a family.
As a "control" method, it involves monitoring the menstrual cycle, and abstaining from sexual intercourse for several days during the middle of the cycle, around the time when the egg is expected to be released. It is assumed that sperms can survive for up to 3 days inside the female reproductive system, and eggs may be fertilised up to 24-36 hours after release, which is difficult to establish if there is much variation in the length of the woman's menstrual cycle. Various methods exist of defining more accurately the so-called "safe period", during which intercourse is unlikely to result in pregnancy.

Barrier methods
Condom Diaphragm The condom or sheath - which fits over the penis, and the diaphragm - which fits over the cervix, both prevent sperms from coming into contact with eggs. Both of these are usually used in conjunction with a chemical spermicide which may be an irritant to some people. These methods are fairly inconvenient and not entirely foolproof.
The condom may also act as a protective against the spread of various sexually transmitted diseases (STDs) - also known as sexually transmitted infections (STIs).

Chlamydia are widespread but not well publicised organisms (on the borderline between bacteria and single celled organisms) which can cause infertility if left untreated.
Gonorrhoea and syphilis are two forms of venereal disease (V.D.) caused by bacteria - which are nowadays curable by antibiotics.
Herpes and HIV are incurable virus diseases, and the latter leads on to the terminal condition AIDS.

- Surgical methods (sterilisation) are among the most reliable and trouble-free ways of preventing pregnancy. Being rather final, they are sometimes used after a couple have had the number of children they want.
Vasectomy involves the cutting of the sperm tubes (vasa deferentia) so that no sperms are present in the semen. No other functions are impaired, and the testes are still in their normal position. It is a relatively simple operation, because the testes are easily accessible.
The female equivalent - cutting or sealing the Fallopian tubes - involves more major surgery because it requires access to the abdomen.

Both of these procedures are fairly drastic, and it is not easy to reverse them. This may be a problem for some people who re-marry and wish to start a second family.

- Hormonal methods can also be used either to decrease or to increase the chances of pregnancy.
The current syllabus requires greater detail on this topic. See later notes.

Pills The oral contraceptive pill is extremely effective, and many women find it very convenient, because it merely involves swallowing a pill every day. Its main biological effect is to prevent the release of an egg, so that the chance of pregnancy is extremely unlikely. In fact the pill contains hormones similar to those produced in differing amounts during different phases of the menstrual cycle and pregnancy: oestrogen and progesterone, which therefore regulate the development of the lining of the uterus, cervical mucus and ovulation. However, it may also have a number of biological side-effects, and there are several formulations with different doses amd combinations of hormones. There are also objections to "the pill" on moral grounds, and it is not endorsed by the Catholic Church.
It is probably also worth emphasising that the oral contraceptive pill, although offering considerable protection against unwanted pregnancy, does not in any way protect against any of the sexually transmitted diseases caused by bacteria or viruses - HIV, VD etc.
Modern developments of hormonal methods include injection or implants of hormone releasing tubes under the skin, which offer long-term protection against pregnancy.

A completely different hormone, commonly called the fertility drug, may be used in some circumstances, in order to increase the chance of pregnancy by stimulating the release of eggs. The dosage required is very crucial, and it may sometimes result in the release of more than one egg. Its use may therefore carry the risk of multiple pregnancy.

Iud - Intra-uterine devices (I.U.D.s) - e.g. "the coil", and "the loop", are structures, usually made of plastic and copper, which are fitted inside the uterus, and may be left in place for several months at a time. These do not prevent fertilisation, but instead they prevent implantation of the ball of cells. This is possibly as a result of a localised reaction to the "foreign body" in the uterus. In some cases, irritation or other complication may rule out this method.
- The intra-uterine system (I.U.S.) is a recent development of this, including slow release of hormones.

- Abortion cannot really be considered as a contraceptive method in the same way as the other techniques outlined above. However, some condone it if it is known that the baby may be born with a serious handicap, or if the mother's health may be in danger.
The procedure involves removing the developing embryo from the wall of the uterus, either by mechanical or chemical means. Once deprived of the support of the female reproductive system, the foetus dies.
The biological and moral issues involved in a consideration of the reproduction process are indeed fundamental, especially as they are effectively matters of potential life and death.

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