Fracture and chemical composition of the deposit formed on the Lippes loop after prolonged use

Abstract

In order to confirm or refute the theory that there is the need to replace IUD's every few years due to their breaking, 26 Lippes Loops were tested. The sediment found on the devices was composed mainly of calcium carbonate. After removal of the sedimentation, it was seen that there was some corrosion of the body of the devices which caused a decrease in the IUD thickness. Pressure tests showed that an IUD which has been in use for a long period of time is more rigid, has less ability to deform and breaks under less pressure. It seems that the current medical opinion stating that IUD's should be replaced every few years, is valid.

PIP: This study was carried out to confirm or refute the theory that IUDs need to be replaced every few years due to their breaking. Fracture and chemical composition of the deposit formed on 26 Lippes Loops after prolonged use (up to 7 years) were analyzed. The sediment consisted of calcium carbonate (77.2-83.1%), magnesium (.32-.41%), sodium (1.7-2%), and zinc (.14-.21%). The amount of sediment increased the longer the IUD was in the uterus without a change in chemical composition. The length of time in use also caused an increase in rigidity, a decrease in flexibility, and a decrease in the structural thickness of the IUD. After 1 year of use a pressure of 75 kg would only cause a depression while an IUD which had been in use for 5.5 years would break under a pressure of 25 kg. It is concluded that the current medical opinion stating that IUDs should be replaced every few years is a valid theory.