Abstract

PIP: From 1976 until June 1978, 1708 medicated IUDs were inserted in nulliparous (64%), oligoparous (e.g., 1-2 births; 29%), and multiparous women (7%). 53% of the women in this study were nulligravida. The women had been fitted with CuT 200 devices with normal (32 mm) and adapted (15-30 mm) long transversal arms (n = 1550), 7 Cu 200 (n = 60), ML Cu 250 (n = 83) and T progesterone-releasing devices (n = 16). Because most women were nulliparous or oligoparous, with correspondingly small uteri and narrow cavities, prefit measurements of length and width of each individual cavity had to be taken in order to avoid dimensional incompatibility, found to be the main reason for unwanted side effects and high termination rates in intrauterine contraception. The Cavimeter, a new measuring device, was invented to enable the operator to measure cervical length, total length (the difference is the cavity length), fundus transversal, and to determine the shorter optimal fundus transversal corresponding to uterus contractions (e.g., during menstruation). Determination of cavity width appears more important than determination of length when using an IUD with a flexible shaft. Generally, the adapted Cu 200 IUD gives the best results concerning termination rates for medical reasons as well as expulsion rates (0.3%). The shorter the transversal arm of the CuT 200, the higher the acceptance rate. It is interesting to note that adaption of medicated IUDs does not lead to a higher pregnancy rate. The low expulsion rate allows the shortening of the plastic filaments intracervically. Both shortening the plastic filaments and dipping the IUD-holding tube into a 5% Betadine solution before insertion are simple methods to avoid ascending infection. Research efforts should be directed to the formulation of an easy method for outlining the uterine cavity, and to the changes in the design and dimensions and the chemical composition of the device, so as to develop a softly malleable device which can mold itself to the unseen and unmeasured uterine cavity.