Users of Periodic Abstinence in Developing Countries Have Fewer Abortions Than Contraceptive Users
Natural Family Planning

Richard J. Fehring
Reprint from Current Medical Research
Vol 15, No 1-2, Winter/Spring 2004
Washington, DC
Reproduced with Permission

According to studies conducted through the auspices of the United Nations, at the turn of the (21st) century approximately 27 million (2.6%) couples of reproductive age world-wide were using some form of periodic abstinence (PA) as a means of child spacing. Of these 27 million couples, 21 million came from developing countries. Researchers recently reported a survey study among users of PA in 15 developing countries: 1) to determine if correct knowledge of the fertile period leads to better use-effectiveness; 2) to determine if unwanted pregnancies from PA users are more or less likely to be aborted than unwanted pregnancies from women using other forms of contraception; and 3) to identify the characteristics of couples who choose to use PA rather than other methods.(1)

The data for this study came from 4 Asian, 2 sub-Sahara African, 2 Arab and 7 Latin American countries that participated in a nationally representative survey conducted under the Demographic Health Survey (DHS) UN project. The respondents were women between the ages of 15 and 49 years. Based on the number of reported pregnancies while using PA the researchers determined gross pregnancy rates with life-table procedures. With 8,387 documented PA-use episodes they calculated a median 12-month probability of pregnancy of 23.6 per 100 episodes. The highest pregnancy rate was 38 per 100 in Jordan, and the lowest 12 per 100 in Nicaragua. However, when the researchers factored in a "correct knowledge of the fertile period" the overall pregnancy rate decreased by 12%. The researchers also found that women who used PA and experienced "unwanted" pregnancies were less likely to report an abortion (or miscarriage) than those who experienced an unintended pregnancy with modern methods of contraception (15% vs. 23%) or with another so called traditional method (15% vs. 35%). PA use was more likely to be used by older women and single women, by more educated women, and by women who have exceeded their family size. However, those women who had less than the desired amount of children were more likely to choose PA than women who achieved their desired family size.


A limitation of this study is that the survey questionnaire did not make a distinction between abortions and miscarriages. However, the researchers did indicate that it was reasonable to assume that the majority were induced abortions rather than miscarriages. They indicated that abortion is severely restricted in all study countries except Armenia and Kazakhstan, and that "under reporting is to be expected and abortion/miscarriage probabilities should be regarded as lower-bound estimates." (p.20) Another confounding variable is what they include as PA - i.e., self devised calendar methods to modern NFP methods! PA was defined in the questionnaire as "Every month that a woman is sexually active she can avoid having sexual intercourse on the days of the month she is most likely to get pregnant." Current users are then asked how they determined the days of sexual abstinence with the following pre-coded responses, calendar, body temperature, cervical mucus / Billings method, both or no specific system. It would be nice to find out how the abortion/ miscarriage rates compared with women who used modern NFP systems.

Another interesting finding is the level of knowledge of the fertile period among PA users. Only 62% of PA users were able to identify "in the middle of the cycle,"as the correct answer to knowledge of the fertile period. The other choices in the survey were - "during her period," "right after her period," and "just before her period." The correct knowledge among current users of PA ranged from a low of 8.2% in Zimbabwe to a high of 90.6% in Kazakhstan. Users of PA in the Philippines had a surprising low percentage of correct answers (25.7%). The researchers concluded that up to half of the 21 million PA users in developing countries are probably practicing an entirely erroneous version of the calendar method.(RJF)


1. Che, Y., Cleland, J.G. and Mohamed, M.A. Periodic abstinence in developing countries: an assessment of failure rates and consequences. Contraception. 2004;69:15-21.