Determinants of contraceptive use dynamics in Thailand: an analysis of contraceptive status calendar.

Thailands official policy to reduce fertility started in 1970 when the total fertility rate (TFR) was 6 children/women with a 15% contraceptive prevalence rate among married women aged 15-44. By 1987 TFR had decreased to 2.1 children and contraceptive prevalence increased to 70.5%. In the 1987 Survey of Determinants and consequences of Contraceptive Use Pattern (CUPS) a contraceptive use status calendar was used in a representative sample of 6835 ever-married women aged 15-49 with socioeconomic fertility history and contraceptive behavior information. The prevalence of sterilizations and injectables started increasing as of 1975 while IUD use declined. Variables were defined indicating monthly transition of use status for a 12-month period ending 3 months prior to the interview. A monthly record of pill injectable or IUD use was set down for each woman. The continuation rate was very low for pill users during the first 3 months and most switched to another method. The probability of discontinuation was high for pills moderate for injectables and low for IUDs. Older women were more likely to switch from pills (completed family size) while the likelihood of failure and discontinuation was higher among younger women. The number of children was significant among pill users while the continuation rate was lower among women with fewer children who were likely to switch to another method. Multiparous women were less likely to switch methods. Women getting IUDs from a public source were more likely to continue while those getting them from a private source tended to switch to another method shortly. The failure rate was much higher in the Northeast. More education was linked to pill use and lower failure rates. Women in agriculture were most rational in injectables use and switching was most widespread among nonagricultural working women.