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A Prospective Study Assessing the Effects of Introducing the Female Condom in a Sex Worker Population in Mombasa, Kenya
Global Health Sciences Literature Digest
Published November 3, 2006
Journal Article

Thomsen SC, Ombidi W, Toroitich-Ruto C, Wong EL, Tucker HO, Homan R, Kingola N, Luchters S.A Prospective Study Assessing the Effects of Introducing the Female Condom in a Sex Worker Population in Mombasa, Kenya. Sex Transm Infect. 2006 Oct;82(5):397-402.


To assess the impact and costs of adding female condoms to a male condom promotion and distribution peer education program for sex workers in Mombasa, Kenya.

Study Design

A twelve-month pre- and post-intervention evaluation.


Study participants were female sex workers who lived and/or worked in the Kisauni division of Mombasa district in Kenya, a major seaport and trucking center on the Trans-East African highway. Kisauni is a popular tourist spot, with many bars, guesthouses, and discos.


Participants were recruited through an existing HIV-prevention peer education project run by the International Centre for Reproductive Health in Mombasa. Peer educators provided a list of 329 peer sex workers, which a study team used to randomly select a sample for screening. A total of 210 female sex workers were then eligible based on the inclusion/exclusion criteria, and were interviewed on their sexual behavior every two months for one year. The average age of the study participants was 29 years old, and the average participant used at least one method of contraception.


The intervention consisted of female condom education through peer education and information, education and counseling (IEC) materials, and provision of female condoms starting at month four of the study.

Primary Outcome

The primary outcome was consistent condom use with all sexual partners in the seven days prior to each interview. Consistent condom use could be male condom use, female condom use, or both. Secondary outcomes were the number and proportion of protected sexual acts with different partner types. There was also a separate cost-analysis component used to determine what additional resources would be required to support provision of female condoms through an existing peer promotion program, and the cost-effectiveness of the intervention.


Of the 210 female sex workers in the study, 149 provided data on condom use consistently. Among this group, the proportion of participants reporting consistent condom use with all partners increased from 59.7% to 67.1% (p=0.04) following the introduction of female condoms. Forty-two percent of the previously inconsistent condom users became consistent users at the final visit, but 16% of the previously consistent condom users reported inconsistent condom use at their last visit. The mean number of casual clients, regular clients, and unprotected coital acts also decreased during the study. Use of male condoms declined from 84% per sex act to 57% following the introduction of the female condom. The total cost of the intervention was $54,139, or $258 per participant. If scaled up to reach the 2,382 sex workers in the Kisauni division, the annual cost for the female condom promotion would be $380,081, or $160 per person.


The female condom has some potential for reducing unprotected sex among sex workers. However, given its high cost, and the marginal improvements seen in this study, governments should limit promotion of the female condom in populations that are already successfully using the male condom.

Quality Rating

There is no widely accepted quality-scoring tool for pre/post-intervention evaluations like this study. The design, which had no control group, makes it difficult to separate the effects of the intervention from secular trends. However, given the rarity of female condoms in Mombasa, increased use of female condoms outside the study was not very likely. In addition, the study sample was small and taken from a list of sex workers generated by peer educators, and may not be representative of other sex workers who do not participate in similar peer education groups. With the exception of the cost-analysis portion, measures were self-reported and subject to bias. Other biases noted by the authors were the numerous discussion sessions held with the study participants during the intervention, which likely were a co-intervention and may have positively influenced some of their responses.

In Context

The main result from this study, the introduction of the female condom into a male condom program, resulting in a small increase in the proportion of sex workers reporting 100% condom use with all partners, replicates what has been found in other sex workers (1,2) and high-risk populations.(3,4,5) However, increases may not always be accompanied by decreases in sexually transmitted diseases and may be due to over-reporting.

Programmatic Implications

The high cost of the female condom alone would represent a substantial investment by a ministry of health, and it seems unlikely that a similar free female condom distribution intervention could take place without donor assistance. However, in situations where male condoms are not consistently used, introduction of the female condom to sex workers can provide them with a safe strategy to prevent HIV and other STIs.


  1. Fontanet AL, Saba J, Chandelying V, Sakondhavat C, Bhiraleus P, Rugpao S, Chongsomchai C, Kiriwat O, Tovanabutra S, Dally L, Lange JM, Rojanapithayakorn W. Protection against sexually transmitted diseases by granting sex workers in Thailand the choice of using the male or female condom: results from a randomized controlled trial. AIDS 1998; 12: 1851-9.
  2. Ray S, van De Wijgert J, Mason P, Ndowa F, Maposhere C. Constraints faced by sex workers in use of female and male condoms for safer sex in urban Zimbabwe. J Urban Health. 2001 Dec;78(4):581-92.
  3. Musaba E, Morrison CS, Sunkutu MR, Wong EL. Long-term use of the female condom among couples at high risk of human immunodeficiency virus infection in Zambia. Sex Transm Dis. 1998 May;25(5):260-4.
  4. Artz L, Macaluso M, Brill I, Kelaghan J, Austin H, Fleenor M, Robey L, Hook EW. Effectiveness of an intervention promoting the female condom to patients at sexually transmitted disease clinics. Am J Public Health. 2000 Feb;90(2):237-44.
  5. Feldblum PJ, Kuyoh MA, Bwayo JJ, Omari M, Wong EL, Tweedy KG, Welsh MJ. Female condom introduction and sexually transmitted infection prevalence results of a community intervention trial in Kenya. AIDS. 2001 May 25;15(8):1037-44.