Before any new method of family planning is released for use by the public, or introduced into the national family welfare programme, it needs to be tested carefully on a small number of volunteers. Only after the results of these initial clinical trials are assessed is a decision taken on using the new method. It is, in fact, studied very carefully before being accepted even for clinical trials.

A chemical compound, styrene maleic acid, is being evaluated nowadays as a male contraceptive. Injected into the vas deferens of men, it causes a condition known as azoospermia, which results in the annihilation of sperms, making it impossible for a man to father a child. Tested in over 50 men, the method, developed at IIT, New Delhi, by Prof. S. K. Guha and his colleagues, doesn't seem to have any serious side effects but is being studied for its reversibility.

Another method being tested involves administration of two substances at the same time. Together, testosterone enanthate and cyproterone acetate, appear to decrease the fertilising capacity of men without affecting their libido.

Till date, no trials have been carried out on Indian men, but these will be initiated soon. A combination of testosterone enanthate and depo provera, which has been released for women as an injectable contraceptive to be administered every three months, is also likely to be administered to Indian men to study its effectiveness. These three approaches to contraception in men will be watched with great interest.

A long-acting injectable contraceptive, Norplant, is being clinically evaluated as a contraceptive for women. Norplant-II consists of two silastic rods containing laevonorgestrol. These are inserted, or implanted, under the skin. The drug is slowly released and remains effective for some years. Studies have shown that Norplant induces menstrual disturbances, which is perhaps why Indian women haven't taken to this method readily. This contraceptive is being tested at selected medical colleges in the country.

Norethisterone enanthate is another injectable contraceptive, which is effective for two months. It has also been subjected to clinical trials in India. Again, though it is effective, it has been found to cause bleeding disturbances. Quinacrine pellets, meanwhile, have been clinically evaluated in the country. But these pellets induce certain side-effects and more work needs to be done on animals before these can be considered for further clinical use in India.

A locally effective barrier method, known as Consap, which contains extracts from the plant Sapindus trifoliatus, has been tested on women by the Central Drug Research Institute, Lucknow. But more tests are needed before it can be released for use. Some of these methods undergoing clinical trials are to be available for use in the years to come.

Copyright © 1997 Indian Express Newspapers (Bombay) Ltd.