For example, eight of 36 people who bought Postpill in the pharmacy said that periodic abstinence was their main method of birth control.
After each of them had tested separately for HIV, they stopped using condoms and relied on periodic abstinence.
As the experience of many couples shows, such practices foster enhanced communication between spouses, in that a successful program of procreative responsibility through periodic abstinence requires discussion of various factors, cooperation, and mutual sacrifice.
Considering difficult circumstances, the state of fallen human nature and the loss of original justice (such that the appetites are not integrated under the dominion of reason and will), the regulation of fertility through periodic abstinence is often difficult, even to the point of requiring heroic virtue.
In an analysis using information from 18 developing countries (including the Philippines), the average failure rate was 22% for periodic abstinence
and 15% for withdrawal, compared with 7% for the pill, 10% for the condom and IUD, and 2-3% for injectables.
The median results from the most recent survey for the 13 countries where both types of information were available show that 59% of those using condoms at last coitus had earlier in the interview reported current use of this method for family planning, 7% reported current use of a non-barrier method of contraception; 4% used periodic abstinence
or withdrawal while the rest had repotted no current contraceptive use.
Women were asked whether they had heard of or used periodic abstinence
and their knowledge of the fertile period.
It is unreasonable to expect a married couple to restrict family size using periodic abstinence
While acknowledging that the so-called rhythm method "involves sacrifices and periodic abstinence
from intercourse," Chaput wrote that "when lived prayerfully and unselfishly, natural family planning deepens and enriches marriage and results in greater intimacy -- and greater joy.