Barriers are the oldest form of contraceptive.
They are not popular in the present day and age because a definite decision that has to be made for their use at a particular time. With spontaneous lovemaking, there is the danger that they will be forgotten. The failure rate varies with each apparatus and depends a lot on mutual ability to insert and remove the particular barrier efficiently. The Diaphram is made of rubber with a reinforced spring rim which fits over the cervix. There are various sizes and it has to be fitted by your doctor who will show you how to use it effectively and how to make sure it is in place.