Rhythm Method

(Natural Family Planning Method)


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The safe period or the rhythm method of birth control is a natural birth control method in which the couple either do not have sexual intercourse during the time when the woman is likely to get pregnant or uses a barrier contraceptive like condoms during sexual intercourse at this time. It is a part of the group of brth controls known as the Natural Family Planning Methods (NFP). The NFP also includes other methods such as coitus interruptus, symptom-based fertility awareness methods and the lactational amenorrhea method.

This method is based on the fact that a woman is not fertile on all days of her menstrual cycle.

There are certain days in which chances of pregnancy are very high, while in other days the chances are much lower.

The rhythm method is not very effective. The rate of pregnancy may be as high as 9% or even higher.

How the Rhythm Method is Used

To use this natural family planning method of birth control, a good idea about the female partner's menstrual cycle is necessary. This can be done by charting the days of the menstrual period for at least 6 months and recording changes in the cervical mucus and the basal body temperature every day.

Pregnancy Book

Pregnancy Book

In a typical 28 day menstrual cycle, the fertile period is from the 8th day of the menstrual cycle (i.e. the 8th day from the first day of the period) to the 20th day of the cycle. The safe days are the five days of menstrual bleeding, 3 days from the end of bleeding and again 8 days from the beginning of the next cycle.

A rough idea about the safe and fertile times in a menstrual cycle can be gauged by assuming that the fertile period extends from seven days before ovulation to seven days after ovulation.

The safe and fertile days have to be calculated for each woman separately as the ovulation and the duration of the menstrual cycle of all women are different.

The image below indicates the safe and fertile days in women with a 21 day cycle or a 28 day cycle or a 35 day cycle. The black bar indicates the days of menstruation.

Rhythm Method for Natural Family Planning, Safe Birth Control

Advantage of the Rhythm Method

Disadvantage of the Rhythm Method

  • The natural family planning method is applicable only to women with a regular menstrual cycle. It cannot be used in the early teen years or around the time of the menopause when the menstrual cycles tend to become irregular.

  • It can deprive the couple of spontaneous sexual intercourse.

  • Coitus is dictated by calculation and arithmetic, rather than spontaneous desire.

  • It is not a definite method of avoiding pregnancy and pregnancy rates are high.

  • It does not protect against sexually transmitted disease.

  • An accurate menstrual cycle chart must be maintained to make the rhythm method of birth control successful.

  • It needs considerable will power on the part of the couple to avoid intercourse or to use a barrier contraceptive like condoms on the fertile days.

Also Read-

Pregnancy Book

Pregnancy Book



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