Background & Objective : The fast population growth is one of the basic problems in Iran and using family planning devices has a remarkable role in decreasing it. The findings of researches carried out nationwide indicate the effectiveness of instruction in the application of family planning methods and devices. The objective of this study is determining the level of knowledge of 15-49 year-old women under Ardabil health and treatment center services.

  Methods : 138 qualified mothers were chosen randomly from among 15-49 year-old women under Ardabil health and treatment centers services. These subjects were selected from among 14 centers (10 mother from each center) and had secondary school level of education. This descriptive cross-sectional and prospective research was conducted by filling out the pre-planned questionnaire and preparing educational booklets and giving them to the mothers under the study as pretest and post-test procedures during the time span of December 2000 to May 2001.

  Results : No meaningful relationship was found between employment and utilizing family-planning devices. The results of Mc-Nemar test and t-test showed that statistically the instruction given with regard to the method of beginning to take anti-gestation pills, method of the intervals of taking the anti-gestation pills, taking measures at the time of forgetting to take anti-gestation pills, the preference of vasectomy to tobectomy, the interval between the injection of anti-gestation ampoules and the duration of IUD effectiveness before and after studying the manuals demonstrated a significant difference.

  Conclusions : Education plays an important role in increasing the knowledge level of the population under study and hence it improves their performance about family planning. So this instruction is recommended to be followed seriously.