Awareness-Based (FAB) methods of family planning involve identification
of the fertile days of menstrual cycle, whether by observing fertility
signs such as cervical secretion and basal body temperature or by
monitoring cycle days.
FAB methods can be used in combination with abstinence or barrier
methods during fertile period1.
The fertile period can be calculated by the woman herself using
the following methods :
woman counts calendar days to identify the start and the end of
the fertile period based on the length of previous menstrual cycles.
She calculates the fertile period by subtracting 18 days from the
shortest cycle and 10 days from the longest cycle which give her
the first and last days of the fertile period respectively.
For example, a womans menstrual cycle varies from 25 to 30 days,
the fertile period will be from 7th (25-18) to 20th (30-10) day
of the cycle, counting day one as the first day of the menstrual
period. However, where such calculations are not possible, the couple
can be advised to abstain between 8th to 22nd day of the cycle (Govt.
of India 1978)2.
fertile period begins when woman notices cervical secretions at
the introitus and lasts till 4 days after the peak day of slippery
body temperature (symptothermic
Rise in temperature of 0.2 to 0.5oC (0.4o
to 1.0oF) occurs around the time of ovulation. Thus the
couple should abstain from 1st day of menstrual cycle till the rise
of temperature remains for three days.
no systemic side-effects
very little or no cost
can be used by most couples, no major
contraindication to use
no effect on breast milk
efficacy is lower than other reversible methods
requires couple motivation and commitment
cannot be used reliably in women with
vaginal discharge, fever or during breast-feeding
calender method is unsuitable for women
with irregular cycles.
does not protect against STI/HIV
1.4 Contraindications and
is no medical contraindication to the use of FAB methods. Certain
clinical conditions make the use of these methods either less efficacious
or difficult, due to complexity in calculating the fertile days.
women with vaginal discharge and fever
cannot calculate accurately the fertile days based on cervical
secretion and basal body temperature measurement.
in immediate post-partum or post-abortal
period and in nursing mothers, the ovarian function is not sufficient
to produce detectable fertility signs.
women with irregular cycles or on drugs
which affect cycle length e.g., lithium, tricyclic anti-depressants,
anti-anxiety drugs, certain antibiotics and anti inflammatory
drugs, are not suitable for using calender method.