Introcaso, Camille E. MD*; Xu, Fujie MD, PhD†; Kilmarx, Peter H. MD‡; Zaidi, Akbar PhD*; Markowitz, Lauri E. MD*
Male circumcision (hereafter referred to as circumcision) is the removal of the foreskin of the penis. The overall circumcision prevalence in the United States is high.1 Largely as a result of physicians’ advocacy for its positive effects on health, neonatal circumcision became a common routine procedure in the United States in the mid-20th century.2 However, there was little systematic evidence to support such claims, and in 1971, the American Academy of Pediatrics (AAP) recommended against routine neonatal circumcision.3 A US population-based study suggested that the circumcision prevalence in men born in the 1980s decreased compared with the prevalence among those born in the 1960s and 1970s.1 However, during the 2 decades after the AAP’s recommendation against routine circumcision, multiple observational studies demonstrated health benefits associated with circumcision. These health benefits include reduced risk of infant urinary tract infections,4 reduced risk of penile carcinoma,5 and reduced risk of sexually transmitted diseases including human immunodeficiency virus (HIV) infection in heterosexual men.6,7 The AAP then revised its policy on newborn circumcision in 1999, stating that “existing scientific evidence demonstrates potential medical benefits of newborn male circumcision; however, these data are not sufficient to recommend routine neonatal circumcision.”7
Since 2005, 3 randomized controlled clinical trials in sub-Saharan Africa have demonstrated that circumcision reduces the risk of female-to-male transmission of HIV by 50% to 60%.8–10 In light of these data, AAP again revised its policy on newborn circumcision to state that “preventive health benefits of elective circumcision of male newborns outweigh the risks of the procedure...benefits of this procedure are sufficient to justify access to it for families choosing it and to warrant third-party payment for circumcision of male newborns.”11 Since 2007, the World Health Organization and the Joint United Nations Programme on HIV/AIDS have recommended that circumcision be recognized as an efficacious intervention for HIV prevention in countries with heterosexual epidemics, high HIV prevalence, and low circumcision prevalence.12 The United States as a whole does not fit this description; HIV is most commonly transmitted through male-to-male sexual contact,13 overall HIV prevalence is low compared with the African countries in the studies, and reports have estimated circumcision prevalence to be high.1 However, HIV prevalence in the United States in some sexual networks and cities is high; for example, in Washington, DC, overall HIV prevalence was recently estimated to be 3%.14 In addition, some subpopulations of US men have a higher risk for heterosexually acquired HIV infection and therefore do fit the World Health Organization profile of a population that might benefit from circumcision. A US HIV incidence analysis estimated that 16,560 new heterosexually acquired infections occurred in men and boys 13 years and older in 2006 to 2009.13 Although most of the US population is white, among those heterosexually acquired infections, 10,900 occurred among black/African American men, 3290 occurred among Hispanic/Latino men, and 2400 occurred among white men.13 A recent cost-effectiveness analysis also found that newborn circumcision in the United States is a cost-saving HIV prevention intervention for black/African American and Hispanic men.15 However, the study noted that the infants and men who could benefit the most from circumcision might have the least access to it because of lack of insurance coverage and state Medicaid policies that do not cover routine circumcision.15
Data from the National Health and Nutrition Examination Surveys (NHANES) conducted in 1999 to 2004 showed that circumcision prevalence in men born from 1940 to 1989 varied by race/ethnicity in the United States, with a prevalence of 88% in non-Hispanic whites, 73% in non-Hispanic blacks, and 42% in Mexican Americans.1 This previous study also reported that circumcision prevalence among those born in the 1980s was significantly lower than that among those born in the 1970s.1 In the current study, we estimated circumcision prevalence in the United States by birth year cohort, race/ethnicity, health insurance type, and family income level from more recent nationally representative surveys—NHANES 2005–2010. Our objectives were to describe the prevalence of circumcision in the United States in different demographic groups and to describe the characteristics of uncircumcised men and boys potentially at increased risk for heterosexually acquired HIV infection.
Study Population and Survey Design
The NHANES are ongoing, cross-sectional surveys designed to compile nationally representative health statistics of the US civilian, noninstitutionalized population through complex, multistage probability sampling (http://www.cdc.gov/nchs.nhanes.htm).16 Briefly, a nationally representative sample of the US civilian, noninstitutionalized population is interviewed and undergoes a medical examination, during which biologic samples are obtained. Specific populations, for example, adolescents, non-Hispanic blacks, and Mexican Americans, are oversampled in some years. Survey data from multiple years are usually combined to achieve adequate sample sizes for reliable national estimates. The NHANES data collection was approved by the National Center for Health Statistics Ethics Review Board (http://www.cdc.gov/nchs/nhanes/irba98.htm), and informed consent was obtained from all participants.
As part of NHANES 2005–2010, health examinations were conducted in specially equipped mobile examination centers. The questionnaire module on circumcision status and sexual behaviors was administered to participants aged 14 to 59 years in a mobile examination center private room using audio computer-assisted self-interview in English or Spanish. Medical artwork of a circumcised and an uncircumcised penis was used as a visual aid. The respondent indicated his circumcision status by selecting the picture that best illustrated the appearance of his penis.1 Sexual behaviors including the number of female partners in the past year were assessed as part of this module. Men and boys who answered “yes” to the question “have you ever had vaginal, anal or oral sex?” were asked additional questions about their sexual histories. The data used for participants aged 18 to 59 years are publically available (http://www.cdc.gov/nchs.nhanes.htm). A recent Centers for Disease Control and Prevention (CDC) report proposing behavioral HIV risk factors for surveillance suggested monitoring the percent of the general public reporting more than 1 sexual partner in the last year.17 Based on this recommendation for surveillance data and because, in the future, providers might recommend circumcision as an HIV risk reduction strategy for men who have multiple female partners,18 we defined men and boys as potentially at increased risk for heterosexually acquired HIV infection as those reporting 2 or more female partners in the last year. By using this broad definition of risk, we produce results that might inform future cost analysis of recommending circumcision to adult men at potentially increased risk for heterosexually acquired HIV infection.
We estimated the prevalence of circumcision by demographic factors including year of birth, race/ethnicity, health insurance type, and family income level. The year of birth for each participant was calculated by subtracting his age at the time of the survey from the second year of the 2-year period during which the survey took place. All prevalence estimates were weighted to represent the US civilian, noninstitutionalized population, to account for survey participants’ unequal probabilities of selection and to adjust for nonresponse.16,19 Differences in prevalence among categories of participants (eg, race/ethnicity) were assessed using the χ2 test. Variance of the prevalence estimate was estimated by Taylor series expansion (linearization) method.20,21 These variance estimates were used in calculating the confidence intervals (CIs). We used logistic regression to examine the association between circumcision prevalence and race/ethnicity while adjusting for potential confounders: year of birth, health insurance type, and family income. We also calculated the percentage of men and boys potentially at increased risk for heterosexually acquired HIV infection, defined as those reporting 2 or more female sex partners in the last year. Relative standard error was calculated for each estimate, and we noted any estimates with more than 30% relative standard error. We calculated the absolute number of uncircumcised men and boys with 2 or more female partners in the last year using data from the 2009–2010 Current Populations Survey (http://www.cdc.gov/nchs/tutorials/nhanes/faqs.htm). We used data from NHANES 2005–2010 to describe the characteristics of this population of uncircumcised men and boys potentially at increased risk for heterosexually acquired HIV infection. We used SAS survey procedures (SAS 9.2 software; SAS Institute Inc, Cary, NC) to analyze these data.
Circumcision Prevalence Overall and by Demographics
During NHANES 2005–2010, 6294 men and boys aged 14 to 59 years answered questions about circumcision status and sexual behaviors. Less than 1% of eligible participants refused to answer or answered “Do not know” to these questions. The estimated overall prevalence of circumcision was 80.5%. Overall circumcision prevalence peaked at 83.3% among men born from 1960 to 1969. Men and boys born most recently, from 1990 to 1996, had a circumcision prevalence of 76.2%, which was significantly lower than the peak (P < 0.001). The prevalence of circumcision differed significantly by race/ethnicity (P < 0.001). Non-Hispanic whites had the highest circumcision prevalence, 90.8%, followed by non-Hispanic blacks who had a prevalence of 75.7%. Mexican Americans had the lowest circumcision prevalence at 44.0% (Table 1).
Circumcision prevalence by birth year cohort varied somewhat among the racial/ethnic groups (Fig. 1). Mexican Americans comprised a greater proportion of the population born from 1970 to 1996 than of the population born from 1940 to 1969. This differential contribution resulted in the overall prevalence of circumcision peaking in men born from 1960 to 1969, whereas among both non-Hispanic whites and non-Hispanic blacks, circumcision prevalence peaked among those born from 1970 to 1979 (Fig. 1). Circumcision prevalence was lower among those non-Hispanic white and non-Hispanic black men and boys born from 1990 to 1996 compared with the peak, although the difference was not statistically significant.
Circumcision prevalence also differed significantly by health insurance type and family income level (P < 0.001; Table 1). Among men and boys with private insurance, circumcision prevalence was higher than those with either public insurance or no insurance. Similarly, the circumcision prevalence was higher in those whose family income was above the poverty level compared with those whose income was at or below the poverty level.
Even after adjusting for potential confounders including birth year cohort, health insurance type, and family income level, circumcision prevalence differed significantly by race/ethnicity. Non-Hispanic whites still had the highest circumcision prevalence, followed by non-Hispanic blacks and finally Mexican Americans.
Characteristics of Uncircumcised Men and Boys at Potentially Increased Risk for Heterosexually Acquired HIV Infection
Overall, 19.1% (95% CI, 17.1%–22.2%) of men and boys aged 14 to 59 years reported 2 or more female partners in the last year and thus fit our definition of those potentially at increased risk for heterosexually acquired HIV infection. Of these men and boys, 19.6% (95% CI, 16.9%–22.7%) were uncircumcised. In 2010, this corresponded to an estimated 3.5 million uncircumcised men and boys aged 14 to 59 years with 2 or more female partners in the last year.
Almost half (45.4%) of the uncircumcised men and boys reporting 2 or more female partners in the last year were born in 1980 to 1996 (aged 14–30 years). Non-Hispanic whites and non-Hispanic blacks each accounted for approximately 23% of this population, and Mexican Americans accounted for 28%. Nearly half (48.3%) of this group of men and boys reported having no health insurance, and 29.3% reported living at or below the poverty index (Table 2).
For decades, there has been increasing evidence of health benefits related to circumcision, including decreased risk of infant urinary tract infections, penile carcinoma, high-risk types of human papillomavirus infections, genital ulcerative disease, and heterosexually acquired HIV infection in men.4,5,8–10,22,23 These data have led international health organizations to call for increases in circumcision among populations with relatively low circumcision prevalence and high risk of heterosexually acquired HIV infection.12 Our data indicate that the overall US population has a high prevalence of circumcision; this finding is consistent with the results from an analysis of NHANES data from previous years.1 Although we report high overall circumcision prevalence, our data also suggest several ways in which circumcision status might contribute to the HIV epidemic in the United States. First, we found that circumcision prevalence in men and boys born from 1990 through 1996 was significantly lower than that in those born from 1960 through 1969. Increased controversies over neonatal circumcision and decreasing insurance coverage for neonatal circumcision have likely contributed to the decrease in circumcision prevalence demonstrated by our study. Over the last decades, neonatal circumcision has become increasingly controversial in the United States; opponents of neonatal circumcision raise ethical questions about parents’ rights to consent to the procedure and concerns about possible complications and potential loss of sexual enjoyment.24 Possibly related to this controversy and to the AAP’s previous policies not supporting routine neonatal circumcision, Medicaid funding for routine neonatal circumcision is lacking in 16 states.25 A 2009 study by Leibowitz and colleagues26 demonstrated that a lack of Medicaid payments for routine neonatal circumcision was associated with lower rates of circumcision. This decrease in circumcision prevalence might be abated in the future owing to the recent revision of the AAP policy, which comprehensively addresses the benefits of neonatal circumcision and specifically calls for third-party payment for routine neonatal circumcision.11
We found significant differences in circumcision prevalences among racial/ethnic groups; those with private, public, and no health insurance and those who live above or at/below the poverty level. Specifically, the estimated prevalence of circumcision was lower among non-Hispanic blacks and Mexican Americans than that among non-Hispanic whites, similar to previous reports of circumcision prevalence.1 Of note, a recent HIV surveillance study reported that the proportion of estimated incident HIV infections among men attributed to high-risk heterosexual contact (defined as sex with an HIV-infected partner or with a partner with a known risk factor for HIV infection) was highest among African Americans at 20%, followed by 8% among Hispanics (including the category Mexican American), and, finally, 3% among whites.27 We found lower and possibly decreasing circumcision prevalences among the racial/ethnic groups most at risk for heterosexually acquired HIV infections, a situation that might contribute to race/ethnicity-based health disparities in HIV infection.28
Our study also describes the characteristics of the estimated 3.5 million uncircumcised men and boys who we defined as at potentially increased risk for heterosexually acquired HIV infection. A recent report of a CDC consultation on circumcision suggested removing financial barriers for elective adult circumcision for men who are at risk for heterosexually acquired HIV infection.18 Importantly, in our study, almost half of the uncircumcised men and boys potentially at increased risk for heterosexually acquired HIV infection reported having no health insurance, and almost one third reported living at or below the poverty index; both of these circumstances create financial barriers to obtaining adult circumcision. Financial barriers limit access for the men who might most benefit from adult circumcision; this is likely to lead to increased health disparities.28
Our analysis is subject to several limitations. First sexual behaviors, in particular the number of female sex partners in the past year and a participant’s circumcision status, were based on self-report. At least one prior study reported 95% agreement or greater between self-reported and clinician-assessed circumcision status,29 although in a study among minority youth in the United States, agreement was lower.30 Second, all demographic questions refer to the patient’s status at the time of taking the survey, not at the time of circumcision; therefore, these results do not indicate determinants for circumcision, but rather associations. Finally, factors other than the number of female partners in the last year, specifically the risk of HIV infection in those sex partners, affect risk for heterosexually acquired HIV infection, and our definition might not adequately represent this risk. However, we chose this definition because it is likely to be similar to assessment tools used by clinicians when evaluating an individual patient’s risk for heterosexually acquired HIV infection. For example, a report of a recent CDC consultation listed “referral of uncircumcised men who engage in unprotected penile-vaginal sex and have behavioral risk for HIV (e.g. multiple partners and prior STDs) to comprehensive HIV-prevention counseling as well as education about and access to voluntary male circumcision...” as an important next step in preventing new HIV infections.18
Our results demonstrate that in the United States, 2 of the racial/ethnic groups of men with the highest rates of new heterosexually acquired HIV infection, non-Hispanic blacks and Hispanics, might also have the lowest circumcision prevalence. Circumcision prevalence is also lower among those likely to have current financial barriers to obtaining it; the poor, publically insured, and uninsured. Furthermore, circumcision prevalence among the population of boys born most recently has decreased significantly compared with those men born in the 1960s. However, in the last 5 years, we have learned that circumcision can significantly decrease the risk of heterosexually acquired HIV infection. Our data will be useful for cost analysis and programmatic recommendations concerning circumcision in the United States.
1. Xu F, Markowitz LE, Sternberg MR, et al. Prevalence of circumcision and herpes simplex virus type 2 infection in men in the United States: The National Health and Nutrition Examination Survey (NHANES), 1999–2004. Sex Transm Dis 2007; 34: 479–484.
2. Alanis MC, Lucidi RS. Neonatal circumcision: A review of the world’s oldest and most controversial operation. Obstet Gynecol Surv 2004; 59: 379–395.
3. American Academy of Pediatrics CoFaN. Standards and Recommendations for Hospital Care of Newborn Infants, 5th ed. Evanston: American Academy of Pediatrics, 1971: 144.
4. Wiswell TE, Geschke DW. Risks from circumcision during the first month of life compared with those for uncircumcised boys. Pediatrics 1989; 83: 1011–1015.
5. Maden C, Sherman KJ, Beckmann AM, et al. History of circumcision, medical conditions, and sexual activity and risk of penile cancer. J Natl Cancer Inst 1993; 85: 19–24.
6. Weiss HA, Quigley MA, Hayes RJ. Male circumcision and risk of HIV infection in sub-Saharan Africa: A systematic review and meta-analysis. AIDS 2000; 14: 2361–2370.
7. American Academy of Pediatrics Task Force on Circumcision. Circumcision policy statement. American Academy of Pediatrics. Task Force on Circumcision. Pediatrics 1999; 103: 686–693.
8. Auvert B, Taljaard D, Lagarde E, et al. Randomized, controlled intervention trial of male circumcision for reduction of HIV infection risk: The ANRS 1265 Trial. PLoS Med 2005; 2: e298.
9. Bailey RC, Moses S, Parker CB, et al. Male circumcision for HIV prevention in young men in Kisumu, Kenya: A randomised controlled trial. Lancet 2007; 369: 643–656.
10. Gray RH, Kigozi G, Serwadda D, et al. Male circumcision for HIV prevention in men in Rakai, Uganda: A randomised trial. Lancet 2007; 369: 657–666.
11. Task Force On Circumcision. Circumcision policy statement. Pediatrics 2012; 130: 585–586.
12. World Health Organization U. WHO/UNAIDS Technical Consultation on Male Circumcision and HIV Prevention—Research Implications for Policy and Programming. Montreux, 6–8 March 2007. Geneva: World Health Organization Press, 2007: 16.
13. Prejean J, Song R, Hernandez A, et al. Estimated HIV incidence in the United States, 2006–2009. PLoS One 2011; 6: e17502.
14. Health GotDoCDo. District of Columbia HIV/AIDS, Hepatitis, STD, and TB (HASTA) Annual Report 20102010.
15. Sansom SL, Prabhu VS, Hutchinson AB, et al. Cost-effectiveness of newborn circumcision in reducing lifetime HIV risk among U.S. males. PLoS One 2010; 5: e8723.
16. Statistics NCfH. Plan and operation of the Third National Health and Nutrition Examination Survey, 1988–94. Series 1: Programs and collection procedures. Vital Health Stat 1 1994; 1–407.
17. Lansky A, Drake A, DiNenno E, et al. HIV behavioral surveillance among the U.S. general population. Public Health Rep 2007; 122 (suppl 1): 24–31.
18. Smith DK, Taylor A, Kilmarx PH, et al. Male circumcision in the United States for the prevention of HIV infection and other adverse health outcomes: Report from a CDC consultation. Public Health Rep 2010; 125 (suppl 1): 72–82.
19. Statistics NCfH. Analytic and Reporting Guidelines The National Health and Nutrition Examination Surveys (NHANES). Hyattesville, MD: Centers for Disease Control and Prevention, 2005: 14.
20. Fuller WA. Regression analysis for sample survey. Sankhya 1975; 37 (3 series C): 117–132.
21. Woodruff RS. A simple method for approximating the variance of a complicated estimate. J Am Stat Assoc 1971; 66: 411–414.
22. Weiss HA, Thomas SL, Munabi SK, et al. Male circumcision and risk of syphilis, chancroid, and genital herpes: A systematic review and meta-analysis. Sex Transm Infect. 2006; 82: 101–109; discussion 10.
23. Warner L, Ghanem KG, Newman DR, et al. Male circumcision and risk of HIV infection among heterosexual African American men attending Baltimore sexually transmitted disease clinics. J Infect Dis 2009; 199: 59–65.
24. Morris BJ, Bailey RC, Klausner JD, et al. Review: A critical evaluation of arguments opposing male circumcision for HIV prevention in developed countries. AIDS Care 2012. Epub ahead of print 2012 Mar 28.
25. Clark SJ, Kilmarx PH, Kretsinger K. Coverage of newborn and adult male circumcision varies among public and private US payers despite health benefits. Health Aff (Millwood) 2011; 30: 2355–2361.
26. Leibowitz AA, Desmond K, Belin T. Determinants and policy implications of male circumcision in the United States. Am J Public Health 2009; 99: 138–145.
27. Centers for Disease C, Prevention. Subpopulation estimates from the HIV incidence surveillance system—United States, 2006. MMWR Morb Mortal Wkly Rep 2008; 57: 985–989.
28. Leibowitz AA, Desmond K. Infant male circumcision and future health disparities. Arch Pediatr Adolesc Med 2012; 166: 1–2.
29. Castellsague X, Bosch FX, Munoz N, et al. Male circumcision, penile human papillomavirus infection, and cervical cancer in female partners. N Engl J Med 2002; 346: 1105–1112.
30. Risser JM, Risser WL, Eissa MA, et al. Self-assessment of circumcision status by adolescents. Am J Epidemiol 2004; 159: 1095–1097.