Contraceptives spermicidal

Innumerable drugs have come under suspicion. Those for which evidence of safety was subsequently found include diazepam, oral contraceptives, spermicides, and salicylates. Naturally the subject is a highly emotional one for prospective parents. A definitive list of unsafe drugs is not practicable. Much depends on the dose taken and at what stage... 

In the last several decades, physical properties of vaginal contraceptive formulations have been improved to deUver spermicide more effectively and enhance consumer compliance. The formulation that deUvers the spermicide can affect the efficacy of vaginal contraceptives (86,87). Formulations currentiy available include jeUies, creams, suppositories, aerosol foams, and foaming tablets. Each consists of a relative inert base material that serves as a carrier for the chemically active spermicide and blocks to some extent the passage of sperm. 

The male barrier contraceptive device is known as the condom, or mbber, and is widely available in most countries. The condom is a mbber or latex sheath, sometimes packaged with a lubricant and spermicide, which serves as a cover for the penis and a receptacle for semen. The method is very effective if the condom is of good quaUty, remains on, and is replaced for each subsequent intercourse. It was reported that 6 biUion condoms were used in 1990 (101). Usage appears to be increasing as adjunctive use with other methods of contraception for prevention of HIV or other sexually transmitted diseases. By rough estimate, condoms may have been used in more than 13 biUion acts of sexual intercourse that risked unwanted pregnancy, HIV, and/or other sexually transmitted diseases (101). 

It is obvious that these commonalties can be tailored to achieve successful contraceptive formulations with varying degrees of efficacy, user friendliness, and aesthetics. U.S. marketed contraceptive products all contain N9 as the spermicide at various concentrations. These products rely only on the mechanism of sperm destruction by the nondiscriminating surfactant effects of the spermicide, as effects of the carrier system on sperm motility are generally minimal. No claim of activity against STDs and HIV are made by current contraceptive products, with the exception of full barrier methods such as condoms. 

A series of DCE-based formulations containing Igepal CO-630 Special (N9) and dextran sulfate (DS) were evaluated for in vitro contraceptive testing. Also included in the screening tests were placebos, N9, two commercial spermicidal products (Conceptrol and KY Plus), vaginal moisturizer products (KY Jelly and Replens ), and saline. Test results are summarized in Table 6. The N9-containing products exhibited similar spermicidal activity, as illustrated by the minimum effective concentration (MEC). Samples without N9 did not have spermicidal activity. DCE placebo vehicle inhibits sperm penetration into the cervical mucus, illustrated by the very low MOET values after 1 10 and 1 160 dilutions. This activity has not been reported for anionic or nonionic polymer vehicles. There are no striking differences... 

For a review of such tests C-H. Lee. Review in vitro spermicidal tests. Contraception 1996, 54, 131-147. 

Spermicides kill sperm. They are not completely effective as contraceptives when used alone but they improve the effectiveness of barrier methods. For centuries, women have used a variety of substances in conjunction with pads or sponges to prevent conception. Acids, such as vinegar, lemon juice and even Coca-Cola, restrict the motility of sperm, so that movement through the vagina is significantly restricted. 

On the day after week 4 ends, a new 4-week cycle is started by applying a new patch. Under no circumstances should there be more than a 7 day patch-free interval between dosing cycles. If there are more than 7 patch-free days, the woman may not be protected from pregnancy and back-up contraception (eg, condoms, spermicide, diaphragm) must be used for 7 days. 

First day start - For first day start, apply the first patch during the first 24 hours of the menstrual period. If therapy starts after day 1 of the menstrual cycle, a nonhormonal back-up contraceptive (eg, condoms, spermicide, diaphragm) should be used concurrently for the first 7 consecutive days of the first treatment cycle. 

There is now a new day 1 and a new patch change day. Back-up contraception (eg, condoms, spermicide, diaphragm) must be used for the first week of the new cycle. 

Use after childbirth - Women who elect not to breast-feed should start contraceptive therapy with the norelgestromin/ethinyl estradiol transdermal patch no sooner than 4 weeks after childbirth. If a woman begins using the patch postpartum and has not yet had a period, consider the possibility of ovulation and conception occurring prior to use of the patch, and instruct her to use an additional method of contraception (eg, condoms, spermicide, diaphragm) for the first 7 days. 

Cesari et al. (2007) demonstrated on bovine and human sperm in vitro that potato aspartic proteases 1 and 3 are effective spermicidal compounds. Spermicidal activity is due to membrane permeabilization and is not related to the proteolytic activity. Cesari et al. (2007) suggest vaginal contraception as a possible applieation. 

Simpson JL, Phillips OP. Spermicides, hormonal contraception and congenital malformations. Adv Contracept 1990 6(3) 141-67. 

Maintenance of vaginal acidity Bacterial vaginosis Spermicidal contraception... 

Saltzman, W., and Tena, L. Spermicide permeation through biocompatible polymers. Contraception 43 497-505, 1991. 

These include nonoxynol-9, octoxinol and p-di-isobutylphenoxypoly(ethoxyethanol). Spermicidal contraceptives are useful additional safeguards but do not give adequate contraceptive protection if used alone they are suitable for use with barrier methods. They have two components a spermicide and a vehicle which itself may have some inhibiting effects on sperm activity. Vehicles commonly used include foams, gels, creams and pessaries. 

Nonoxynol-9 is an approved spermicide with strong antiviral activity. A vaginal device which facilitates the controlled release of nonoxynol-9 has been developed for contraceptive and anti-STD purposes. The device, available as a diaphragm or a disk pessary, is fabricated from silicone elastomer matrix system. The drag release profile demonstrates square root time kinetics (M co tV2) (see Section 4.4.2). 

Sterilization Oral contraceptive Condom Spermicide Withdrawal Diaphragm Periodic abstinence Intrauterine device (IUD) Douche... 

The vaginal use of spermicidal substances during sexual intercourse is perhaps the oldest method of contraception. However, the introduction of oral contraceptives and the intrauterine device in the 1960s led to the decay in their use. Since many of these substances also offer protection against sexually transmitted diseases, interest and investigation in this field have recently increased [288], Also, the development of new potential spermicides, namely antibodies [289], contributed to further awareness. Currently used spermicides include nonoxynol-9, octoxynol, benzalkonium chloride, and chlorhexidine. 

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