Copper intrauterine devices are widely used and highly effective (> 99% at one year ) for 5 and some for 10 years. They are especially useful in the over-40s in whom oral contraceptives may become progressively contraindicated and for whom one IUD will last into the menopause. The IUD prevents implantation of the fertilised ovum, and has an additional antifertilisation effect enhanced by the toxic effect of copper ions on the gametes.
Norplant consists of six nonbiodegradable flexible silicone capsules, which release levonorgestrel at a rate of around 30 micrograms per day over a period of five years. It is no longer available for new use but some women who have had the system implanted may retain it till the year 2004. The shorter-acting (2-3 years) single rod containing etonogestrel (Implanon) is now preferred.
Vaginal preparations, used to immobilise or kill (spermicide) spermatozoa, are used to add safety to various mechanical contraceptives. They are very unreliable and should be used alone only in an emergency. Substances used include nonoxinols (surfactants that alter the permeability of the sperm liporotein membrane) as pessary, gel or foam.
Oil-based lubricants cause failure of rubber condoms and contraceptive diaphragms; many 'lubricants', e.g. hand or baby creams, wash off readily, but are nevertheless oil-based. Barrier contraceptive devices made of polyurethane, e.g. the female condom (femidom), are not so affected.
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Are Menopause Symptoms Playing Havoc With Your Health and Relationships? Are you tired of the mood swings, dryness, hair loss and wrinkles that come with the change of life? Do you want to do something about it but are wary of taking the estrogen or antidepressants usually prescribed for menopause symptoms?