Public Health Impact

Women and infants disproportionately bear the long term consequences of STDs. Women infected with Neisseria gonorrhoeae or Chlamydia trachomatis can develop pelvic inflammatory disease (PID), which, in turn, may lead to reproductive system morbidity such as ectopic pregnancy and tubal factor infertility. If not adequately treated, 20% to 40% of women infected with chlamydia¹ and 10% to 40% of women infected with gonorrhea² may develop PID. Among women with PID, tubal scarring can cause involuntary infertility in 20%, ectopic pregnancy in 9%, and chronic pelvic pain in 18%.³ Approximately 70% of chlamydia infections and 50% of gonococcal infections in women are asymptomatic.^4-6 These infections are detected primarily through screening programs. The vague symptoms associated with chlamydial and gonococcal PID cause 85% of women to delay seeking medical care, thereby increasing the risk of infertility and ectopic pregnancy.⁷ Data from a randomized controlled trial of chlamydia screening in a managed care setting suggest that such screening programs can reduce the incidence of PID by as much as 60%.⁸

Gonorrhea and chlamydia can also result in adverse outcomes of pregnancy, including neonatal ophthalmia and, in the case of chlamydia, neonatal pneumonia. Although topical prophylaxis of infants at delivery is effective for prevention of ophthalmia neonatorum, prevention of neonatal pneumonia requires prenatal detection and treatment.

Human papillomavirus (HPV) infections are highly prevalent, especially among young sexually active women. While the great majority of HPV infections in women resolve within one year, they are a major concern because persistent infection with specific types (e.g., types 16, 18, 31, 33, 35, and 45), are causally related to cervical cancer; these types also cause Pap smear abnormalities. Other types (e.g., types 6 and 11) cause genital warts, low grade Pap smear abnormalities and, rarely, recurrent respiratory papillomatosis in infants born to infected mothers.⁹

Genital infections with herpes simplex virus are extremely common, may cause painful outbreaks, and may have serious consequences for pregnant women including potentially fatal neonatal infections.¹⁰

When a woman has a syphilis infection during pregnancy, she may transmit the infection to the fetus in utero. This may result in fetal death or an infant born with physical and mental developmental disabilities. Most cases of congenital syphilis are easily preventable if women are screened for syphilis and treated early during prenatal care.¹¹

Observations

Chlamydia – United States

Between 2004 and 2005, the rate of chlamydia infections in women increased from 480.6 to 496.5 per 100,000 females (Figure 1, Table 4). Chlamydia rates exceed gonorrhea rates among women in all states (Figures A and B, Tables 4 and 13).

Chlamydia – Infertility Prevention Program

In 2005, the median state-specific chlamydia test positivity among 15- to 24-year-old women tested in selected prenatal clinics in 25 states, Puerto Rico, and the Virgin Islands was 8.0% (range 2.8% to 16.9%) (Figure E).

In 2005, the median state-specific chlamydia test positivity among 15- to 24-year-old women who were screened during visits to selected family planning clinics in all states and outlying areas was 6.3% (range 3.0% to 20.3%) (Figures 8 and 9).

Gonorrhea – United States

Gonorrhea rates among women were higher than the overall HP 2010 target of 19.0 cases per 100,000 population¹² in 46 states and two outlying areas in 2005 (Figure B, Table 13).

Like chlamydia, gonorrhea is often asymptomatic in women. Gonorrhea screening, therefore, is an important strategy for the identification of gonorrhea among women. Large-scale screening programs for gonorrhea in women began in the 1970s. After an initial increase in cases detected through screening, gonorrhea rates for both women and men declined steadily throughout the 1980s and early 1990s, and then reached a plateau (Figure 11). The gonorrhea rate for women (119.1 per 100,000 females) increased slightly in 2005.

Although the gonorrhea rate in men has historically been higher than the rate in women, the gonorrhea rate among women has been higher than the rate among men for five consecutive years (Figure 12 and Tables 13 and 14).

Gonorrhea – Infertility Prevention Program

In 2005, the median state-specific gonorrhea test positivity among 15- to 24-year- old women screened in selected family planning clinics in 41 states, Puerto Rico, the District of Columbia, and the Virgin Islands was 1.0% (range 0.0%-3.8%) (Figure 21). Median gonorrhea positivity in family planning clinics has shown minimal change in recent years (1.0% in 2001).

In 2005, the median state-specific gonorrhea test positivity among 15- to 24-year- old women screened in selected prenatal clinics in 20 states, Puerto Rico, and the Virgin Islands was 0.9% (range 0.0% to 3.2%) (Figure F). Median gonorrhea positivity in prenatal clinics has shown minimal change in recent years (0.9% in 2001).

Primary and Secondary Syphilis by State

The HP 2010 target for primary and secondary (P&S) syphilis is 0.2 case per 100,000 population. In 2005, 29 states and two outlying areas had rates of P&S syphilis for women that were greater than 0.2 case per 100,000 population (Table 25).

Congenital Syphilis

The HP 2010 target for congenital syphilis is 1.0 case per 100,000 live births. In 2005, 26 states, Guam, and Puerto Rico had rates higher than this target (Table 38).

The number of congenital syphilis cases closely follows the trend of P&S syphilis among women (Figure 37). Peaks in congenital syphilis usually occur one year after peaks in P&S syphilis among women. The congenital syphilis rate peaked in 1991 at 107.3 cases per 100,000 live births, and declined by 92.5% to 8.0 cases per 100,000 live births in 2005 (Figure 38, Table 37). The rate of P&S syphilis among women declined 94.8% (from 17.3 to 0.9 cases per 100,000 females) during 1990–2005 (Figure 27).

The 2005 rate of congenital syphilis for the United States is currently eight times higher than the HP2010 target of 1.0 case per 100,000 live births.

While most cases of congenital syphilis occur among infants whose mothers have had some prenatal care, late or limited prenatal care has been associated with congenital syphilis. Failure of health care providers to adhere to maternal syphilis screening recommendations also contributes to the occurrence of congenital syphilis.¹³

Pelvic Inflammatory Disease

Accurate estimates of pelvic inflammatory disease (PID) and tubal factor infertility resulting from gonococcal and chlamydia infections are difficult to obtain. Definitive diagnosis of these conditions can be complex.

Hospitalizations for PID have declined steadily throughout the 1980s and early 1990s, but have remained relatively constant between 1995 and 2004 (Figure H). A greater proportion of women diagnosed with PID in the 1990s have been treated in outpatient instead of inpatient settings when compared to women diagnosed with PID in the 1980s.¹⁴

The estimated number of initial visits to physicians' offices for PID from the National Disease and Therapeutic Index (NDTI) has generally declined from 1993 through 2005 (Figure I and Table 42).

In 2003, an estimated 168,837 cases of PID were diagnosed in emergency departments among women 15 to 44 years of age. In 2004 this estimate increased to 170,076 (National Hospital Ambulatory Medical Care Survey, NCHS). As of the date of publication of this report, 2005 data are not available.

Ectopic Pregnancy

Evidence suggests that health care practices associated with clinical management of ectopic pregnancy changed in the late 1980s and early 1990s. Before that time, treatment of ectopic pregnancy usually required admission to a hospital. Hospitalization statistics were therefore useful for monitoring trends in ectopic pregnancy. Beginning in 1989, hospitalizations for ectopic pregnancy have generally declined over time (Figure G). Data suggest that nearly half of all ectopic pregnancies are treated on an outpatient basis.¹⁵

¹ Stamm WE, Guinan ME, Johnson C. Effect of treatment regimens for Neisseria gonorrhoeae on simultaneous infections with Chlamydia trachomatis. N Engl J Med 1984;310:545-9.

² Platt R, Rice PA, McCormack WM. Risk of acquiring gonorrhea and prevalence of abnormal adnexal findings among women recently exposed to gonorrhea. JAMA 1983;250:3205-9.

³ Westrom L, Joesoef R, Reynolds G, et al. Pelvic inflammatory disease and fertility: a cohort study of 1,844 women with laparoscopically verified disease and 657 control women with normal laparoscopy. Sexually Transmitted Diseases1992;9:185-92.

⁴ Hook EW III, Handsfield HH. Gonococcal infections in the adult. In: Holmes KK, Mardh PA, Sparling PF, et al, eds. Sexually Transmitted Diseases, 2nd edition. New York City: McGraw-Hill, Inc, 1990:149-65.

⁵ Stamm WE, Holmes KK. Chlamydia trachomatis infections in the adult. In: Holmes KK, Mardh PA, Sparling PF, et al, eds. Sexually Transmitted Diseases, 2nd edition. New York City: McGraw-Hill, Inc, 1990:181-93.

⁶ Zimmerman HL, Potterat JJ, Dukes RL, et al. Epidemiologic differences between chlamydia and gonorrhea. Am J Public Health1990;80:1338-42.

⁷ Hillis SD, Joesoef R, Marchbanks PA, et al. Delayed care of pelvic inflammatory disease as a risk factor for impaired fertility. Am J Obstet Gynecol 1993;168:1503-9.

⁸ Scholes D, Stergachis A, Heidrich FE, Andrilla H, Holmes KK, Stamm WE. Prevention of pelvic inflammatory disease by screening for cervical chlamydial infection. N Engl J Med 1996;34(21):1362-6.

⁹ Division of STD Prevention. Prevention of Genital HPV Infection and Sequelae: Report of an External Consultants' Meeting. National Center for HIV, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, December 1999.

¹⁰ Handsfield HH, Stone KM, Wasserheit JN. Prevention agenda for genital herpes. Sexually Transmitted Diseases 1999;26:228-231.

¹¹ Centers for Disease Control. Guidelines for prevention and control of congenital syphilis. MMWR 1988;37(No.S-1).

¹² U.S. Department of Health and Human Services. Healthy People 2010. 2nd ed. With Understanding and Improving Health and Objectives for Improving Health. 2 vols. Washington, DC: U.S. Government Printing Office, November 2000.

¹³ Centers for Disease Control and Prevention. Congenital syphilis – United States, 2002. MMWR 2004;53:716-9.

¹⁴ Rolfs RT, Galaid EI, Zaidi AA. Pelvic inflammatory disease: trends in hospitalization and office visits, 1979 through 1988. Am J Obstet Gynecol 1992;166:983-90.

¹⁵ Centers for Disease Control and Prevention. Ectopic pregnancy in the United States, 1990–1992. MMWR 1995;44:46-8.