This trial was designed to compare the efficiency and acceptability of three different chemical contraceptive products — a foaming tablet (Volpar foaming tablets), a pessary (Genexol pessaries), and a new aerosol foam cream (Emko foam), and it was conducted entirely by post. This was the second trial of its kind organized by the Council for the Investigation of Fertility Control. The foaming tablet used was the same as that used in the first trial. Since the result obtained for this preparation in both trials was similar, it was possible to compare the results of all five products used in both trials. It was found that the pregnancy rates for the aerosol foam cream were considerably lower than those for any other chemical contraceptive yet tested in this way. Since it calls for no medical supervision, this would appear to be an important finding. There was little difference in the overall acceptability of the three different products, though the reasons for liking or disliking were different in each case.
An improved system of follow-up was used in this trial, and as a result, information was available for 72% of the possible woman months as compared with only 39·7% in the previous trial.
The writer suggests that the efficiency of the aerosol foam cream (Emko foam) may well be similar to mechanical methods of contraception, and it is hoped that it may be possible to arrange a comparative trial of Emko foam and the two most commonly used mechanical methods, the condom and the diaphragm.