Serum levels of copper and zinc were determined in 11 health women in whom Latex Leaf intrauterine devices (IUDs) containing copper and zinc had been inserted. Patients with low levels of serum copper or zinc before insertion usually had increased levels of either of these metals while using the device, but they did not exceed the upper limits of normal values. When the group was considered as a whole, the serum levels of zinc showed a slight tendency to increase with duration of IUD use, whereas there was no statistical difference between the serum levels of copper before and after insertion of the IUD.
PIP: Serum levels of copper and zinc were measured in 111 healthy women in whom Latex Leaf IUDs containing copper and zinc had been inserted. The women ranged from 21 to 41 years of age. Months of use ranged from 1 to 23 with an average of 14.6. The 1st blood sample was obtained before insertion and the 2nd from 1 to 19 months after insertion. Mean level of serum copper in the 1st sample was 1.42 mcg/ml. Age and parity had no effect; a slight tendency for higher levels was observed only in multigravidas. There were no significant changes in mean copper levels even when the levels were correlated with duration of usage. Mean serum zinc level before insertion was 1.1 mcg/ml with no correlation to age, gravidity, or parity. The 2nd sample showed a slight increase, 109% + or -3.25% standard error p .005. This increase correlated with the time the device was in situ. In general, patients with low levels of serum copper or zinc before insertion usually had increased levels after use but these levels did not exceed the upper limits of normal values. This may be due to an initially low level of the copper fraction bound to serum albumin and indicates the existence of some equilibrium between free and bound metal in the system.