A randomized comparative study of the performance of seven different sizes of the Mahua Ring inserted following measurement of the uterine cavity and one size of the same ring.

A comparative study of the performance of multi-sizes of the Mahua Ring inserted following measurement of the uterine cavity and one size of the same ring assigned at random was carried out from November 1984 to September 1985 at two hospitals in Tianjin. The experiences of 800 acceptors were analysed by life-table techniques. At the end of two years, net cumulative first segment continuation rates of the multi-size and one-size Mahua device were 88.0 and 88.2, respectively. The results revealed that there was no significant difference between the groups. It is suggested that to insert one size of the Mahua Ring is as effective as the insertion of many sizes of the Mahua Ring.