The Development Of IUDs

It is often quoted in manuals of contraception that the forerunners of IUDS were stones that nomads used to put in the uteri of their camels to stop them becoming pregnant. The first known attempt to create an intra-uterine contraceptive device for humans was described in 1909. The device was a loop of thread made from silkworm gut. Later the Grafenberg ring of silver was developed in Germany, and the Ota ring of gold-plated silver in Japan. These were used by some practitioners up to the mid 1930s, when medical opinion rather turned against them. One doctor persevered with IUDS in Israel from 1930-57; he reported a failure rate of 2.5 per 100 woman/years. Interest reawakened in the late 1950s, perhaps as a result of this study; in particular the USA became interested, and popularized several versions in the 1960s.

Progress was helped by the development in the 1960s of biologically safe plastics. This enabled manufacturers to produce IUDS which were pliable, and so could move with the changing shape and size of the uterus through the month, rather than digging in as the rigid metal IUDS did. The pliability also meant that the plastic had a ‘memory’; the IUD could be forced into a narrow applicator for insertion, and would then resume its original shape when it was released in the uterus. Using a narrow tube as an applicator reduced the amount that the cervix needed to be dilated at fitting, which made the process quicker, safer and less painful.

In the late 1960s researchers began to experiment with IUDS wrapped in copper wire. This greatly increased the birth control effect of the device, but the IUDS needed to be changed more frequently. Recently an IUD has been developed which slowly releases progestogen. This too seems to add to the device’s effectiveness. The IUD has always been more popular in some countries than in others. At present there are roughly 60 million tuD-users worldwide, including many in China. In the UK, approximately 4-6% of fertile women are IUD users.