ABSTRACT Intrauterine foreign bodies have been used in animals as a contraceptive since times immemorial. The use of pebbles in camels as a contraceptive has been reported in Arabs. Intrauterine contraceptive devices (IUCDs) have been used since 1962 when the first International Conference of Population Council, New York reported encouraging data on Margulies coil and Lippes loop as IUCDs. According to the World Health Organization, IUCDs are the second most widely used reversible contraceptive method after voluntary female sterilization. Intrauterine contraceptive devices have undergone extensive evolution from Grafenberg ring to Ota ring, Margulies coil, Lippes loop, Birnberg bows, Saf T-coil followed by Cu T 200, Cu 7, Multiload Cu 250/375, Cu T 380 Ag, Cu T 380 S [slimline]. Hormonereleasing IUCDs were developed in 1973. Ombrelle 250/380 and FlexiGard are the latest in this series. The common complications encountered with IUCD insertion are pelvic infections, infertility, the risk of both intrauterine and extrauterine pregnancy, pain, altered bleeding pattern, expulsion of the device, and its migration. Migration of IUCD into the bladder has been rarely reported in the literature. The authors report an unusual case of a secondary vesical calculus formed around a migrated IUCD. How to cite this article Agarwal N, Agarwal BK. Unusual Complication of Intrauterine Contraceptive Device. J South Asian Feder Obst Gynae 2016;8(3):243-245.