Lubricants

September 16, 2011

During the course of sexual arousal, the walls of the vagina secrete a lubricant or mucus to facilitate coitus. Inadequate lubrication, a persistent problem for 40% of women in the United States, can cause vaginal intercourse to be painful. Inadequate lubrication can be facilitated by extended foreplay, and hormonal changes which can occur during the course of menstrual cycles, menopause, and breast-feeding. Water-based lubricants can both alleviate the problem of vaginal dryness and increase sexual stimulation for both partners. However, most importantly, it should be noted that lubricants improve the efficacy rate of condoms, thus reducing the risk of sexually transmitted infections (STIs), including human immunodeficiency virus (HIV).

In general, latex condoms are most effective when used in conjunction with water-based lubricants. Examples of water-based lubricants include KY Jelly and Astroglide. Water-based lubricants can protect latex condoms (barriers) against friction that may otherwise tear them during intercourse. Alternatively, oil-based lubricants should not be used with latex condoms, dental dams, or any other product made of latex. Examples of oil-based lubricants are petroleum jelly, massage oils, or creams. When latex comes in contact with oil-based products, a chemical reaction occurs which degrades the latex. This process can ultimately cause holes to develop in condoms, influence condom breakage, and reduce the amount of protection overall. For example, in a study conducted to assess the impact of lubricants on latex condoms during vaginal intercourse, researchers determined that the use of oil-based lubricants increased breakage in new and aged latex condoms, while water-based lubricants did not impact the breakage rate of new condoms and decreased the breakage rate in aged condoms.

Additionally, condoms lubricated with spermicides are not likely to be more effective than condoms used with other water-based lubricants. Most specifically, in recent times, nonoxynol-9 (N-9), a spermicidal in concentrations of 18% in some sexual lubricants, and lubricated condoms have been noted to contain detergents that disrupt cell membranes. Frequent use of N-9 as a contraceptive has been associated with an increased risk of epithelial infections in the vagina, cervix, and rectum. Such opportunistic infections have been demonstrated by a series of researchers to enhance the transmission of HIv. For example, one study has demonstrated that HIv incidence was greater in a high-risk population using N-9 than in a comparison population using a placebo.

In another study, researchers found that N-9 used without condoms was ineffective against HIv transmission. This study also showed evidence that N-9 increased the risk of HIV infection. It was further noted that this study was conducted among commercial sex workers in Africa who are at an increased HIV risk and used N-9 gel on a frequent basis. As a result of this study, the Centers for Disease Control and Prevention concluded that, given that N-9 has been proven ineffective against HIV transmission and heightens the possibility of risk, with no benefits, N-9 should not be recommended as an effective means of HIV prevention.

Moreover, a similar randomized study of women sex workers revealed a slightly higher risk for gonorrhea, a slightly lower risk for chlamydia, and no change in risk for HIV among women using film with 70 mg of N-9. Taken together, these findings speak the importance of the timely development of a safe, effective microbicidal spermicide that can reduce the transmission of HIV.

Lastly, couples experiencing infertility should avoid the use of all commercial lubricants. Even lubricants that are spermicide free contain ingredients that can inhibit sperm. The reduction of sperm motility and viability after exposure to commercial lubricants in vitro may be related to glycerin contained in lubricants. Researchers have demonstrated significant and immediate inhibition in motility and forward progression when sperm were incubated with 16.7% glycerin. Some natural food products useable as lubricants have proven to be less detrimental to sperm. Of the products tested, canola oil shows the least adverse effect on sperm motility and viability. Overall, studies examining the motility of sperm when exposed to lubricants suggest that when selecting a lubricant couples should consider one that has a minimal effect on pH, demonstrates low spermicidal activity, and has minimal effect on motility. Canola oil satisfies these criteria and has yielded support from several studies.

SEE ALSO: Condoms, Reproductive technologies, Safer sex, Sexually transmitted diseases

Suggested Reading

  • Foley, S., Kope, S. A., & Sugrue, D. P. (2002). Sex matters for women: A complete guide to taking care of your sexual self. New York: Guilford Press.
  • Stewart, E. G., & Spenser, P. (2002). The V book: A doctor’s guide to complete vulvovaginal health. New York: Bantam Doubleday Dell.
  • Wingood, G. M., & DiClemente, R. J. (2002). Women’s sexual and reproductive health. New York: Plenum/Kluwer.

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