Natural family planning
NHS Direct Online Health Encyclopaedia
Natural family planning is a method of contraception where natural indicators are used to identify the womans fertile time each month. In this way pregnancy can be more easily avoided (or aimed for).
Used correctly, natural family planning is 98% effective in preventing pregnancy. However, because the method depends heavily on a number of complicated calculations, many people regard it as too difficult to be a reliable form of contraception.
A week-by-week guide to your pregnancy How does it work?
For each menstrual cycle, a woman is fertile for only 24 hours. However, because sperm can live inside the body for up to a week, the actual fertility period is around eight or nine days. An egg is released about 12 to 16 days before the womans next period.
The fertility period is worked out by keeping a diary of body temperature (which rises slightly after ovulation the period when an egg is released from the ovaries into the fallopian tubes), cervical secretions (discharge becomes clear, like egg white) and the length of menstruation, over several months. The woman must then avoid sexual intercourse during the fertile times to avoid pregnancy.
Women who have recently given birth may not need to use any form of contraception. For this to be effective the woman must have had a baby less than six months ago, be fully breastfeeding (not feeding the baby in any other way), and not be having any periods.
The advantages are:
Most women can use it if they are properly trained and keep accurate records.
If used correctly (usually after professional training), natural family planning is 98% effective.
There are no side effects.
It does not contravene any religious beliefs.
It can be used in conjunction with other methods of contraception such as condoms. This is the most efficient way of using it as a method of contraception.
The disadvantages are:
It relies heavily on the ability to accurately work out the fertile periods each month. If the indicators are not correctly calculated the method has a high risk of failure.
It demands a high level of organisation and it will take as long as six months to discover the fertile period. During this time, the diary of indicators must be keep every day to ensure that the records are accurate.
The indicators may be hard to understand if the woman is tired, stressed or ill.
It does not provide either partner with protection against infection of sexually transmitted diseases.
What is it used for?
Natural family planning is used either to avoid pregnancy, or to increase the chances of becoming pregnant. Using natural family planning methods does not provide protection against infection of sexually transmitted diseases.
Who can use it?
Anyone who learns and fully understands natural family planning can use it effectively.
© Queen's Printer and Controller of HMSO, 2005
Crown copyright material is reproduced with the permission of the controller of HMSO and the Queens Printer for Scotland.