Page:Contraception; 1st ed. (IA in.ernet.dli.2015.94163).pdf/180

The low dome may suit sexually inactive women with small cervical canals, but it does not suit the active pair, for the penis may attempt to invaginate it and, not being able to, may dislodge it instead. Hence I believe some cases of "failure of this method" are due to the use of the small domed variety by couples who should have had the high domed cap.

A further point to be noted in the construction of the cap is that the whole appliance, both rim and cap, should be or very pliable and soft rubber and should not be withered or wrinkled in the slightest degree. Also the line of junction indicated down the fine line in the drawings of C, should be entirely secure, and without the smallest thin area or perforation. I have had sent to me a cap, otherwise perfect, in which a minute bubble in the rubber just at this junction had developed into a hole more than large enough for the entry of the sperm. To ascertain that the line of

junction is secure, the cap should be held up to the light, stretched and examined, preferably with a magnifying glass. But it is far better in every way to use the Pro Race cap in which there is a seamless dome.

In figures A2 and B2 the caps are