Menstrual pattern and blood loss with U-coil inert progesterone-releasing IUDs.

Menstrual blood loss (MBL) was estimated before and after insertion of the U-coil progesterone-releasing device in 37 patients. The same procedure was carried out in 39 cases fitted with an inert U-coil IUD of the same size and shape. Blood loss was estimated by the atomic abosorption technique during the preinsertion cycle and at the 1st, 3rd, 6th, 9th, and 12th postinsertion cycles. MBL was significantly reduced in patients fitted with a progesterone-releasing U-coil compared to those fitted with an inert U-coil who showed a significant increase in MBL. The cycle length was prolonged with the progesterone U-coil, and was reduced with inert U-coil devices. The duration of flow was significantly reduced with the progesterone U-coil and significantly prolonged with the inert device. The incidence of intermenstrual spotting was higher with the progesterone U-coil than with the inert U-coil. The hemoglobin level was significantly increased with the progesterone U-coil while it was significantly reduced with inert U-coil devices.