This investigation, using a case-control analysis approach on an IUD data set from a less-developed country center, delineated four risk factors in patient characteristics that are associated with severe pain at interval IUD insertion. They are: higher education (greater than or equal to seven years), low-parity (1-2 live births), longer open interval (greater than or equal to 13 months) between the end of the last pregnancy and insertion, and non-breastfeeding at the time of insertion. Adjusted relative risks estimated by odds ratios are 2.1, 2.7, 2.7 and 5.0, respectively. For women with a combination of the above risk factors, they have a further increased (additive in nature) risk of suffering severe insertion pain. Similar analysis was also performed on a developed country center data set for which only the effect of education and parity could be studied; an odds ratio of 5.0 for nulliparity was obtained. The plausibility of these findings as well as their clinical and programmatic implications are discussed.

作者：I C, Chi；L F, Galich；P F, Tauber；L R, Wilkens；C S, Waszak；A J, Siemens；J, Lippes

来源：Contraception 1986 年 34卷 5期