IUDs Reassessed: A decade of experience
A decade of international experience with the intrauterine device (I UD) is reviewed. It is estimated that 15 million IUDs are being worn throughout the world. The Lippes loop D is perhaps the most effective IUD in use. The Copper T and Cu-7 devices are appropriate for nulliparous women. The IUD apparently has a differing mode of action from species to species. In humans, the IUD does not interfere with ovulation, corpus luteum formation, or, to some extent, sperm transport and fertilization. However, they do seem to inhibit implantation, possibly through a non-inflammatory cell reaction in the uterus. IUDs are the primary contraceptive method in at least 10 countries, including Taiwan and Korea. However, the experience in India and Pakistan has not met initial expectations. The insertion procedure and equipment used are described. The ideal time for insertion is after abortion or pregnancy. Otherwise, the last few days of menstruation is the best time. General or local anesthesia, paracervical block, or analgesia are not required for IUD insertion, since the procedure is generally not painful. Perforation of the uterus is the most frequent complication during insertion. Net pregnancy rates for IUDs range from 0-5.6 per 100 women during the 1st year of use. The tendency now is to remove an IUD if pregnancy occurs. IUD expulsion rates range from .7-19.3 per 100 insertions after 1 year of use. Removals in the 1st year for bleeding and/or pain range from 4-14.7 per 100 women-years of use. Pelvic inflammatory disease (PID) is the 2nd most frequent reason for removal of an IUD. It is not clear whether the IUD increases the risk of PID. In the United States, pelvic infection is the most common IUD-related symptom requiring hospitalization. 7 of 10 deaths associated with an IUD were the result of pelvic infection. The Dalkon Shield poses the most serious risks related to septic abortion, and is no longer being distributed. The USAID distributed 5,367,310 IUDs during 1969-1974. The new copper-bearing IUDs cause less bleeding than inert devices. The replacement of copper wire with copper sleeves lengthens the life of copper-bearing IUDs. Some of the new devices being tested include Progestasert (progesterone-releasing), the intrauterine membrane, the Spring Coil and the spring steel Ypsilon. Photographs of and data on various IUDs are appended.