Percentage of women experiencing an unintended pregnancy within the first year of use of barrier contraceptive methods1
| Device | Failure rate | |
|---|---|---|
| Typical use | Perfect use | |
| Diaphragms (with spermicide cream or jelly) excluding Caya* |
12% | 6% (range 4.3% to 8.4%) |
| Caya (pregnancy rates from 6 months of use with spermicidal gel extrapolated to give an estimated probability of pregnancy at 12 months) |
17.8% | 13.7% |
| Femcap®* | 13% | 7.7-11.2%5 |
| Male condom* | 18% | 2% |
| Internal condom* | 21% | 5% |
*in the USA
Devices inserted into the vagina to lie diagonally across the cervix and vaginal vault and much of the anterior vaginal
All currently available products are made of silicone
Cap
A cap fits onto the cervix to create a barrier to sperm trying to enter the cervix
FemCap which is silicone, is the only currently available cervical cap.
There are 3 sizes:
Spermicide
Diaphragms and Caps should be used with spermicide .Nonoxyl-9 spermicides are no longer recommended as they can cause vaginal irritation increasing the risk of STI acquisition. Current spermicidal gels products are acid buffering gels, which are thought to have similar efficacy and better tolerability. The manufacturer of Caya® advises use with an acid buffering lubricant, Caya® Gel which contains lactic acid, sodium lactate, cellulose and sorbic acid which acts by reducing the motility of sperm cells (the acidic gel creates a hostile environment inside the vagina) and creating an additional physical barrier in front of the cervix (cellulose is a gel forming agent). Other brands are available such as Contragel ( contains Water Lactic Acid Sodium Lactate (dairy-free) Methyl Cellulose Sorbic Acid Vanillum) 8
Spermicides are class IIa medical devices
NB VCF contraceptive film is a nonoxynol-9 containing product from the USA that can be bought on line in the UK
