Birth control and you – The rhythm method

THE rhythm method is a natural form of contraception that requires a woman to keep abreast of her calendar so she can know her most fertile time of the month and abstain from sex or use a condom during this period.

“This is the most common method being used, but it is not a very sensitive method. In fact, out of all the contraceptive methods that we have, it is the least effective of them all,” said obstetrician/gynaecologist Dr Leslie Meade.

“Sometimes men have what they call a pre-ejaculate and the rhythm method is really them trying to withdraw prior to ejaculation, so you can have semen and sperm in the pre-ejaculate that can cause pregnancy. And also, it is not all the time that the man is going to withdraw at the correct time and so that is an issue with the rhythm method,” he said.

He said the rhythm method is more popular because sometimes sex is not planned and so couples might chance having intercourse without the use of a condom.

In order for this method to be effective at preventing pregnancy, you will have to estimate your time of ovulation and keep track of your menstrual cycle. This cycle varies and so it is advised that you chart your cycle for at least seven months to determine your most fertile period as well as your “safe period” (time when you are less fertile). A woman’s cycle usually varies between 28 to 32 days and ovulation occurs around day 14 in the case of a 28-day cycle. This egg can be fertilised by sperm and result in pregnancy.

“If you have a 21-day cycle, you don’t really have a safe period,” Dr Meade said. “I don’t like to speak about safe period unless I know what the cycle is and when the cycle is.”

Because the rhythm method requires human judgement, it is prone to error and so the rhythm method is said to be about 75 to 85 per cent effective. Women who, for example, have irregular periods, sometimes become pregnant because there is limited scope for keeping track. Women who practise the rhythm method are also asked to note changes in their body temperature, vaginal discharge, mood changes and pelvic cramping which are signs of ovulation.

Given its high failure rate and the high demand it places on memory and calculation, the rhythm method is rarely recommended as a good birth control method, although it has some advantages.

Advantages:

1. It is inexpensive

2. It is natural and so women who are averse to hormonal contraceptive can use it as an alternative

3. It does not affect your ability to become pregnant in the long run

Disadvantages

1. It is not as reliable as other methods.

2. It does not offer protection against sexually transmitted diseases.

3. It requires you to be abstinent or use condoms for some days during the month

4. Requires both partners participation for success.

— Nadine Wilson