Preview Chapter 9

Introduction

This chapter focuses on the epidemiology, diagnosis and management of syphilis and gonorrhea in pregnant women and neonates, and strategies to reach women with STD services.

STD in Pregnancy: Syphilis

Prevalence data

Syphilis prevalence rates between 3 percent and 19 percent have been reported in pregnant women from developing countries.

Impact of Syphilis on Maternal and Child Health

Untreated maternal syphilis may lead to spontaneous abortion, stillbirth, prematurity or congenital syphilis.

Diagnosis of Syphilis

For the purpose of routine screening of pregnant women, the use of only a qualitative rapid plasma reagin test (RPR) without confirmation with TPHA is sufficient and acceptable.

Treatment of Syphilis in Pregnant Women

Recommendations: Benzathine benzylpenicillin: 2.4 MU in a single dose by IM injection or aqueous procaine benzylpenicillin: 1.2 MU daily by IM injection for 10 days; in case of penicillin allergy, use erythromycin: 500 mg orally, four times daily for 15 days.

Control Programs for Congenital Syphilis

Routine serological screening and early treatment of both partners can prevent adverse pregnancy outcome due to syphilis. But syphilis control programs often are inefficient and ineffective.

Cost-Effectiveness of Syphilis Screening in Pregnancy

Screening and treating pregnant women for syphilis is highly cost-effective. In Lusaka, Zambia, the cost of preventing an adverse pregnancy outcome due to maternal syphilis was estimated at around U.S. $12 at a seroprevalence level of 10 percent.

STD in Pregnancy: Gonorrhea

Prevalence data

In most African nations, prevalence rates of gonorrhea in antenatal clinic attenders range from 1 to 15 percent. Among industrialized nations, the U.S. has the highest rates, from 0.6 to 2.7 percent.

Impact of Gonorrhea on Pregnancy Outcome

Reports suggest a link between gonorrhea and premature delivery or very low-weight babies. However, trials with larger sample sizes are needed to provide conclusive evidence.

Gonococcal Ophthalmia Neonatorum (GCON)

Neonates acquire GCON at delivery during passage through the birth canal. If untreated, GCON can lead to blindness, but it is preventable by a simple prophylaxis program.

Prevention and Control

The following strategies can prevent and control GCON in neonates:

• Ocular prophylaxis at birth
• Diagnosis and treatment of GCON
• Diagnosis and treatment of maternal gonorrhea
• Primary prevention of gonoccocal infection among women

Cost-Effectiveness and Feasibility of Proposed Interventions

Although detecting and treating gonococcal infections in pregnancy reduces the incidence of gonococcal ophthalmia neonatorum and other maternal complications, it is expensive and not feasible in most areas of the developing world.

Ocular prophylaxis is more cost-effective (See Table 4). It involves installing 1 percent silver nitrate drops or 1 percent of tetracycline ointment in the newborn's eyes within one hour after birth.

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Introduction

In addition to being risk factors for the sexual transmission of HIV infection, STDs are also a major cause of morbidity, especially in women and children. Particularly urgent is the need to control fetal wastage and congenital abnormalities due to infections that are preventable and curable, such as maternal syphilis and gonorrhea.

The impact of other STDs, including Chlamydia trachomatis, Trichomonas vaginalis or bacterial vaginosis, on pregnancy outcome is still controversial (except for chlamydial ophthalmia neonatorum), and control measures are less obvious. Therefore, this chapter focuses on the epidemiology, diagnosis and management of syphilis and gonorrhea in pregnant women and neonates, and strategies to reach women with STD services.

STD in Pregnancy: Syphilis

Syphilis is a systemic, chronic infectious disease transmitted through sexual intercourse, from mother to infant during pregnancy and through transfusion of infected blood. The causative organism is Treponema pallidum, one of a small group of treponemes that are virulent for humans.

Prevalence Data

Syphilis prevalence rates between 3 percent and 19 percent have been reported in pregnant women from developing countries, with the highest rates found in southeastern sub-Saharan Africa. ^1—8. Rates of congenital syphilis as high as 3,200 per 100,000 live births have been described in Addis Ababa, Ethiopia, ⁹ and 850 per 100,000 in Lusaka, Zambia.¹⁰ In Zambia, 8.6 percent of infants under three months of age admitted to hospitals and 7.5 percent of neonates admitted to intensive care units had congenital syphilis. In Porto Alegre, Brazil, 2.3 percent of the newborns had clinical and/or laboratory incidence of congenital syphilis. ¹¹

Impact of Syphilis on Maternal and Child Health

The devastating effects of maternal syphilis infection on the fetus are well-known. Untreated maternal syphilis may lead to spontaneous abortion, stillbirth, prematurity or congenital syphilis. Vertical transmission of syphilis is common and is a major cause of fetal loss, perinatal and infant death, and long-term severe illness. ^12,13

The greatest effect of syphilis on pregnancy outcome is probably spontaneous abortion. Exact data on spontaneous abortions are difficult to obtain from developing countries, where a large proportion of women do not attend antenatal clinics before the pregnancy is "visible." Pregnant women with clinical signs or symptoms indicating a miscarriage often seek help outside maternal child health (MCH) facilities. Older data from Ethiopia suggest that five percent of all pregnancies are lost due to syphilis, whereas in Zambia, 19 percent of miscarriages may be attributable to syphilis.¹⁴ A case-control study from Nairobi, Kenya, demonstrated an increased risk of 4.3 percent for spontaneous abortion in syphilis-seroreactive women.¹⁵

The relation between syphilis and stillbirth is well-documented. In Zambia, 42 percent of stillbirths have been attributed to syphilis, and congenital syphilis has been implicated in 30 percent of all perinatal deaths.¹⁴ Data from Nairobi show an odds ratio of 4 for stillbirth in syphilis-seroreactive mothers. Table 1 shows data from a recent population-based study in Malawi that quantified the impact of syphilis on stillbirth, neonatal death and infant death. It is important to note that women with RPR titers of þ 1:8 were at greater risk for poor pregnancy outcome, indicating that more recent acquisition of syphilis infection may be more harmful for the fetus.

Congenital syphilis occurs in approximately one-third of the newborns of pregnant women with untreated syphilis, although the stage of syphilis infection is probably the major determining factor. Congenital syphilis is a serious condition, disfiguring and debilitating, if not fatal. Since an infected child can be asymptomatic initially, diagnosis at birth is difficult, and the problem is underestimated in most hospitals.^16,17

Overall, it is estimated that one-third of syphilis-seroreactive pregnancies will result in fetal wastage, one-third in the birth of an infant with congenital syphilis and one-third in the delivery of a healthy, uninfected child. These proportions depend heavily on the stage of disease of the maternal syphilis, with primary and early syphilis being most infectious to the infant. It is less clear how many RPR reactive mothers with latent or already treated syphilis will have adverse pregnancy outcome or an infant with congenital syphilis.

Diagnosis of Syphilis

The primary lesion of syphilis typically presents as a chancre, from 10 to 90 days following exposure. The lesion is usually single but might be multiple, painless and associated with regional adenopathy. Untreated, the primary ulcer heals spontaneously in a few weeks. As a rule, all genital ulcers will be treated for syphilis and chancroid in most geographic areas of the developing world (see Chapter 8). Within a few weeks or months, a variable systemic illness develops, characterized by low-grade fever, malaise, sore throat, headache, adenopathy and cutaneous or mucosal rash. People with serological evidence for syphilis but with no clinical manifestations have latent syphilis.¹⁸

Because the primary lesion is often painless and the secondary stage is characterized by a specific signs and symptoms, a substantial proportion of infected people, particularly women, neglect to seek medical care and are only identified by serological screening. The most commonly used serological tests for screening are the rapid plasma reagin (RPR) test and the Venereal Disease Research Laboratory (VDRL) test, both nonspecific tests (for more details, see Chapter 12). Specific tests are the fluorescent treponemal antibody absorption test (FTA-ABS) and T. pallidum hemagglutination assay (TPHA), which are used as confirmatory tests.

For the purpose of routine screening of pregnant women, the use of only a qualitative RPR without confirmation with TPHA is acceptable and sufficient. A simpler version of RPR developed for finger-prick blood samples, "Teardrop," has been evaluated in field conditions. Because of its low sensitivity (69 percent) it cannot be considered a reliable alternative to the classic serum RPR test.¹⁹

Treatment of Syphilis in Pregnant Women

The duration of treatment for a seroreactive woman and her partner(s) depends on the stage of the infection. Since the majority of women identified through a screening program are in a latent stage, it is difficult to distinguish early from late syphilis. Furthermore, quantifying RPR titers, which may give an indication of disease stage, is not routinely done and often not feasible.

The regimens in the linked image are recommended:²⁰Treatment failures with penicillin therapy in preventing congenital syphilis have been reported, but the timing of therapy was not always mentioned.^12,21 Treatment during the third trimester seems to increase the risk of treatment failure.²² Some experts recommend two or three doses of benzathine penicillin at weekly intervals, especially after 20 weeks of pregnancy.

Diagnosis of Congenital Syphilis

Congenital syphilis has been divided into two clinical syndromes. The features that appear within the first two years of life comprise early congenital syphilis, whereas those that appear after two years comprise late congenital syphilis. Most syphilitic infants do not show signs at birth. Early clinical signs begin to appear in the third to the eighth week of life and consist of snuffles, palmar and plantar bullae, splenomegaly, pallor, joint swelling with or without pseudoparalysis, and cutaneous syphilis. However, none of these signs is entirely pathognomonic.¹⁷

In infants under the age of six months, a reactive RPR or VDRL test is very likely to indicate the presence of antibodies against syphilis, since false-positive reactions are rare in this age group. However, because maternal antibodies can be transferred to the infant, seroreactivity may not indicate active infection. Increasing the titers of reagin antibodies and/or IgM levels or more recent techniques such as PCR might help to identify active infection. These techniques are unavailable in most settings, and by testing the infant valuable time would be lost in the treatment of possible infection.

Treatment of Congenital Syphilis

Penicillin is the drug of choice for treating congenital syphilis. But, a standard dose of benzathine penicillin does not produce detectable penicillin levels in cerebrospinal fluid and is therefore considered inadequate for neonates with nervous system involvement. A dose of 50,000 U procaine penicillin IM per kilogram body weight daily for 10 days is the preferred/recommended treatment. A single IM injection of benzathine penicillin 50,000 U per kilogram body weight is an alternative in situations of noncompliance or possible loss to follow-up.¹⁷ All neonates with a positive RPR or VDRL test should be treated unless the mother has received adequate treatment during pregnancy.

Control Programs for Congenital Syphilis

Adverse pregnancy outcome due to syphilis is preventable through routine serological screening and early treatment of both partners. Because of the high prevalence rate of syphilis in many developing countries, the harmful effects on the unborn child, and the availability of inexpensive and simple diagnostic and treatment facilities, most governments have adopted syphilis control programs for pregnant women. Nevertheless, comprehensive, effective programs are still lacking in most parts of the developing world.

In Zambia, data from two urban and two rural hospitals show that while 92 percent of pregnant women attended prenatal services, less than 30 percent were given a syphilis screening test. Of those found seroreactive, less than one-third were treated.¹ Similar findings were reported from Nairobi, where the existing centralized syphilis control program was found to be very inefficient.³²

Barriers to congenital syphilis prevention programs include the following:

• Late attendance at antenatal clinics
• Logistical constraints, including shortages of laboratory equipment and supplies, drugs and transport facilities
• Lack of well-trained and motivated staff
• Virtually nonexistent partner notification systems
• The "supposed to" syndrome (see Box 2)

However, these barriers to an effective implementation of a congenital syphilis control program can be addressed and improved, taking into account the local conditions. Key strategies include encouragement of early antenatal attendance; serological testing followed by prompt treatment during the first visit; and active partner notification and treatment. Reports from Zambia¹⁰ and Kenya²⁴ have demonstrated that it is possible to encourage health-seeking behavior using appropriate educational methods.

The other key element to success in the Zambian and Kenyan project was the decentralization of RPR testing. Sera were no longer sent to central laboratories but were tested promptly in the antenatal clinic by trained midwives. In addition, in Kenya educational materials were developed to convince mothers to bring their partners in for treatment. These materials focused mainly on the responsibility of both parents to have a healthy baby (see Chapter 11). After this system was introduced in Nairobi, the proportion of syphilis-reactive women and their partners who were adequately treated reached 92 percent and 50 percent, respectively.²⁴ The Zambian pilot study showed that under field conditions in a developing country, the prevention program helped reduce the adverse pregnancy outcome due to syphilis by two-thirds.

Cost-Effectiveness of Syphilis Screening in Pregnancy

In a high-prevalence urban area, STDs represent a substantial proportion of the entire disease burden of that population. Under the Healthy Life Days Lost per Capita ranking system, syphilis ranks fifth in importance after measles, HIV, malaria and gastroenteritis in a high-prevalence urban area.³⁴

Screening and treating pregnant women for syphilis is known to be a highly cost-effective, inexpensive and feasible intervention for congenital syphilis, as illustrated by a demonstration project in Lusaka, Zambia. Hira and his co-workers calculated the cost of preventing an adverse pregnancy outcome due to maternal syphilis at around U.S. $12 at a seroprevalence level of 10 percent.10 Even in countries with seroreactivity rates lower than 1 per 1,000, syphilis screening in pregnant women was reported to be cost-effective.²⁶

Conclusions and Recommendations

• Prenatal screening and treatment of pregnant women for syphilis is cost-effective, even in low-prevalence areas, and should be applied globally.

• Intensive health education to motivate women to attend antenatal clinics early in pregnancy is an important component of a syphilis control program.

• Women have to be tested and treated as early as possible in pregnancy. Performing a qualitative RPR/VDRL test on the spot while the woman is waiting for the result can enhance the program's effectiveness.

• If the screening test is positive, treatment with benzathine benzylpenicillin 2.4 MU IM must be given immediately. If the patient is more than 20 weeks pregnant, treatment should be repeated after one week.

• In areas with a high prevalence and incidence of syphilis, repeat screening is recommended in the third trimester.

• Partner notification and treatment is an important strategy (see Chapter 11).

• Unless both partners are treated adequately, a baby born to a seroreactive mother should be treated with 50,000 U procaine penicillin IM per kilogram body weight daily for ten days. A single IM injection of benzathine penicillin 50,000 U per kilogram body weight is an alternative therapy in situations where noncompliance or loss to follow-up is a possibility.

• Internal quality control of the RPR/VDRL tests should be included in every program. If possible, samples should be sent regularly to referral laboratories for external quality control.

STD in Pregnancy: Gonorrhea

Prevalence Data

Prevalence rates of gonococcal infections in pregnant women show wide geographical variations. Among the industrialized countries the United States has the highest rates, ranging from 0.6 to 2.7 percent. In most European countries the gonorrhea prevalence rate in pregnant women is virtually always below one percent.

In most African countries prevalence rates in ante-natal clinic attenders range from 1 to 15 percent.^2,27—30 The paucity of data published from other continents suggest that some, but not all, countries have prevalence rates similar to those of African populations.³¹ Although most of these studies were done in urban settings, high rates also have been documented in rural areas in Cameroon, for example.³² Gonorrhea rates vary not only between different countries, but also differ greatly within a developing country.

Overall, gonococcal infection remains a common STD in the developing world, and the gap with the western world (at least Western Europe, where gonorrhea is disappearing) is only increasing.

Impact of gonorrhea on pregnancy outcome

Earlier reports (mostly retrospective studies and case reports) have suggested an association between maternal gonorrhea and premature delivery. ^33,34 A case control study conducted in Kenya on the association of specific sexually transmitted diseases with preterm birth confirmed these previous findings.³⁵ Women with gonorrhea had a threefold increased risk to deliver a premature baby. A more recent, larger study in the same setting showed that maternal gonococcal infection was associated with an increased risk (odds ratio 3.2) of very low-weight babies (<1,500 g), not with prematurity (all babies < 2,500 g included).³⁶

The role of maternal chlamydial infection in prematurity is more debatable. Only women with chlamydial infection with elevated IgM level were found to have an increased risk for prematurity.³⁷ Therefore, proposing public health interventions specifically aimed at preventing premature delivery caused by N. gonorrhoeae and C. trachomatis is arguable. However, selective intervention trials may contribute to a better understanding of their role, if any, in causing premature delivery. Only trials with a very large sample size will provide meaningful information, since the number of premature deliveries attributable to infection with these microorganisms is expected to be low.

There is increasing evidence that both gonococcal and chlamydial infection heighten the risk of postpartum infections. In a study conducted in Nairobi, 20 percent of delivering mothers developed clinical postpartum infection within seven to 28 days after delivery, and approximately 50 percent of these infections could be attributed to N. gonorrhoeae, C. trachomatis or both.³⁸ The magnitude of the contribution of postpartum infections to secondary infertility is still unclear.

Gonococcal Ophthalmia Neonatorum (GCON)

From a public health perspective, GCON is without any doubt the most important complication of gonorrhea in pregnancy. It is a frequent and severe condition that can eventually lead to blindness. It is important to understand that GCON is preventable by a simple prophylaxis program.

Definition and transmission from mother to child

Ophthalmia neonatorum is defined as a purulent conjunctivitis, with at least one polymorphonuclear cell per high power field on a Gram stain of an eye smear, in infants younger than 30 days old. Ophthalmia neonatorum can be caused by a number of pathogens, but the two main ones are N. gonorrhoeae and C. trachomatis. Although these organisms produce different patterns of disease (GCON tends to be more severe, more purulent and it has an earlier onset), the etiological cause cannot be presumed from clinical signs alone.

Neonates acquire gonococcal ophthalmia neonatorum at delivery during passage through the infected birth canal. Occasionally diseases have been transmitted to infants delivered by Caesarean section after prolonged rupture of the membranes.³⁹ The transmission rate from mother to child in the absence of ocular prophylaxis has been estimated in two prospective studies in Africa (Table 2). In Nairobi, gonococcal ophthalmia developed in 28 of 67 babies whose mothers had N. gonorrhoeae infections, a transmission rate of 47 percent. In Cameroon, 30 percent of exposed babies became infected. These transmission rates result in alarmingly high incidence rates of gonococcal ophthalmia neonatorum of 3.6 and 4 per 100 live births, respectively. By comparison, incidence rates of GCON in the Western world average 0.06 percent.

Clinical picture

Gonococcal ophthalmia begins one to thirteen days after birth. It is most often bilateral and purulent with the conjunctivae and eyelids swollen and hyperemic. If untreated, corneal involvement can appear as diffuse epithelial edema, giving the cornea a hazy, grayish appearance. Coarse white opacities (infiltrations) appear near the border of the cornea and the sclera, and may enlarge and become ulcerated by the end of the second or third week. These ulcerations can lead to perforation of the cornea, resulting in loss of vision. When new blood vessels invade the cornea, corneal scarring may occur. Effective treatment dramatically changes the course and outcome of the disease, usually with noticeable improvement within 24 hours.

It is difficult to estimate the risk of blindness associated with gonococcal ophthalmia. In 1880, the incidence of gonococcal ophthalmia in Stuttgart, Germany, varied from one to 14 percent, and 20 to 78 percent of the children in institutions for the blind had a history of the disease. After ocular prophylaxis at birth was introduced, the incidence dropped dramatically, and the percentage of institutionalized children with blindness caused by gonococcal ophthalmia steadily declined. Today in many developing countries, the incidence of gonococcal ophthalmia is still high, although blindness in children is not reported to be highly prevalent. However, blind children have a higher mortality rate, so the true extent of the problem would not be apparent in prevalence surveys. In a clinic-based study of 64 neonates with gonococcal ophthalmia, 16 percent proved to have corneal involvement.⁴⁰

Prevention and Control

Four different strategies are possible for preventing and controlling gonococcal ophthalmia in neonates:

• Ocular prophylaxis at birth
• Diagnosis and treatment of GCON
• Diagnosis and treatment of maternal gonorrhea
• Primary prevention of gonococcal infection among women

Ocular prophylaxis at birth

Transmission of N. gonorrhoeae from the maternal cervix to the newborn's eyes can be interrupted by giving prophylactic drops immediately after birth. Three different regimens have been recommended: (1) silver nitrate 1 percent eye drops, (2) tetracycline 1 percent eye ointment, or (3) erythromycin 0.5 percent eye ointment.

Only the first two regimens have been evaluated prospectively in areas with a high proportion of multiresistant gonococcal strains, including penicillinase-producing N. gonorrhoeae (PPNG).⁴¹ The results of this trial in Kenya demonstrated the equal and high efficacy of silver nitrate drops and tetracycline ointment in preventing gonococcal ophthalmia (see Table 3). The attack rates among exposed newborns receiving silver nitrate or tetracycline were 7 percent and 3 percent, respectively. These findings are consistent with risk estimates of transmission from mother to child when prophylaxis is given.³⁹

There are a number of explanations for reported failures of ocular prophylaxis to prevent neonatal ophthalmia. They include failure to instill the agent directly into the conjunctival sac, flushing of the eye after administration of silver nitrate (to prevent chemical conjunctivitis) and postpartum infection either by autoinoculation or from other infected persons.

Silver nitrate is inexpensive but it can be associated with benign chemical conjunctivitis. If the product is badly preserved (e.g., open bottles) it can evaporate, and increased concentration of the product can be toxic to the eyes. It is therefore recommended that silver nitrate be stored in a closed, dark bottle and transferred to small containers for daily use. Commercially available, single-dose ampoules are much more expensive and less readily available.

Tetracycline is non-toxic and may remain longer in the eye because it is an ointment. Multidose preparations are cheap and widely available in developing countries. Erythromycin ointment is expensive and less available in many countries.

Muhe and Tafari⁴² have shown that a delay in prophylaxis of more than four hours after birth is associated with a four- to five-fold increase in risk of gonococcal ophthalmia. Prophylaxis therefore should be given as soon after birth as is practical–preferably within one hour–for both hospital and home births. Traditional birth attendants' kits should include a dispensing system for eye prophylaxis.

Ocular prophylaxis is operationally the most feasible and cost-effective strategy for preventing gonococcal ophthalmia in neonates. In areas with a high prevalence of gonococcal infections in pregnant women, prophylaxis at birth for all infants should be introduced immediately as an initial step in reducing neonatal morbidity related to sexually transmitted disease in pregnancy.

Diagnosis and treatment of GCON

Early diagnosis and appropriate treatment of GCON are critically important because the infection can lead rapidly to blindness. Even in the case of a well-established, comprehensive ocular prophylaxis program, cases of GCON can occur. If cases of GCON are reported frequently, efforts should be made to reinforce or introduce 100 percent coverage of ocular prophylaxis.

WHO recommends the approach for management of ophthalmia neonatorum shown in Figures 1 and 2.²⁰ The rationale behind the flowcharts is that every severe case of ophthalmia neonatorum should be considered and treated as GCON unless N. gonorrhoeae can be excluded by gram stain. WHO has proposed several treatment regimens for GCON for areas with a high prevalence of PPNG:²⁰

Some countries with low prevalence of gonococcal infections, such as the Netherlands, have adopted the strategy of diagnosis and treatment of complications in newborns. The neonatal infection is taken as the indicator of an infection in the parents; screening during pregnancy is not performed. In very low-prevalence areas with good health service coverage, this strategy may be the most cost-effective, but it has never been evaluated. Unfortunately, in most developing countries where gonococcal infections are still prevalent, diagnostic facilities and appropriate treatment regimens are not easily available. Control programs should adopt ocular prophylaxis strategy as a first priority, while still making treatment of GCON available.

Case finding and treatment of gonococcal infections during pregnancy

Detecting and treating gonococcal infections in pregnancy has the advantage of reducing the number of cases GCON, as well as other maternal complications such as postpartum endometritis or premature delivery. Several limitations, however, make it difficult to define precise strategies for finding and treating gonorrhea in women.

First, more than half of pregnant women with gonococcal infection are asymptomatic, and clinical signs associated with this infection (such as vaginal discharge or cervical mucopus) are not sufficiently sensitive or specific.⁴³ Vuylsteke and co-workers demonstrated that the classic WHO flowchart that starts with vaginal discharge as a complaint has a very low sensitivity and specificity for detecting gonococcal cervicitis, when used as a screening tool in both low- and high-risk women.⁴³

Furthermore, the gold standard diagnostic test for gonococcal infection in women is bacteriological culture, which is neither available nor practical in most antenatal care settings. At present, a test to diagnose gonococcal and/or chlamydial infection in women (pregnant or non-pregnant) that is simple, rapid, affordable and valid does not exist. Some encouraging data from Zaire and Tanzania showed that diagnostic approaches which involve epidemiologic risk markers resulted in an acceptable validity, but further field evaluation in different cultural settings is needed.^43,44 (For further discussion, see Chapter 8.)Mass treatment of gonococcal infection during pregnancy would only be indicated if it were shown to be more cost-effective than other detection programs. Considering the expensive and often unavailable antibiotics required for such a program (because of the limited options for treatment of gonorrhea during pregnancy), this strategy is not advisable. An additional argument against this strategy is women's lack of involvement in the diagnosis. The lack of a diagnosis also precludes the notification of partners.

Prevention of gonorrhea in women

In principle, women can be prevented from acquiring gonococcal infection through prevention (condom use and/or behavior modification). Prevention has not received high priority in STD control programs in the past, and, therefore, has not been very successful. With the emergence of a lethal and incurable viral STD–HIV–major efforts have been invested in promoting condom use and safer sexual behavior.

Data on the reduction of gonorrhea prevalence in pregnant women as a result of AIDS campaigns are not yet available. It should also be stressed that women are often at risk for gonococcal infection because of the sexual behavior of their stable male partner rather than from their own sexual behavior. In these cases, partner reduction messages are irrelevant for women.³

Cost-Effectiveness and Feasibility of Proposed Interventions

Although detecting and treating gonococcal infections in pregnancy reduces the incidence of gonococcal ophthalmia neonatorum and other maternal complications, it is a very expensive (if the goal is to reduce gonococcal ophthalmia) and operationally complicated strategy. Currently, it is not feasible in most areas of the developing world.In Table 4, the cost of ocular prophylaxis is compared with the cost of early diagnosis and treatment of gonococcal ophthalmia in a group of 1,000 women with a prevalence of gonococcal infection of 10 percent. The cost for 1,000 prophylactic regimens is U.S. $100 for silver nitrate 1 percent drops (single-dose wax ampoules ophta doses) and U.S. $50 for tetracycline 1 percent ointment (multidose tubes for ten babies–U.S. $0.5 per tube). The price of one treatment regimen for gonococcal ophthalmia varies from U.S. $5 (125 mg IM of ceftriaxone in a single dose) to U.S. $2 (75 mg of kanamycin plus topical tetracycline).⁵¹ It is assumed here that the best conditions would apply, meaning that each case of gonococcal ophthalmia would be brought back to a healthcare facility and receive appropriate treatment.

The total cost of the three programs: silver nitrate, tetracycline and no prophylaxis for a group of 1,000 women (with a prevalence of gonorrhea of 10 percent) would be U.S. $135, U.S. $65 and U.S. $235 respectively. This results in a cost per adverse outcome averted of U.S. $2.9, U.S. $1.4 and U. S. $5. Indirect costs of visual impairment due to late or inadequate treatment are not taken into account.

It is clear that the strategy of ocular prophylaxis is more cost-effective than early diagnosis and treatment. Furthermore, it is more convincing on humanitarian grounds, especially in areas where efficacious drugs are not readily available. In low-prevalence areas of maternal gonococcal infection (less than 1 percent), the cost of ocular prophylaxis may be higher than that of treating the cases of gonococcal ophthalmia that occur. But, without adequate treatment, the potential risk of blindness warrants further use of ocular prophylaxis in all countries where the health care coverage is not optimal.

Conclusions and Recommendations

• Gonorrhea is still prevalent among pregnant women in many developing countries. It can result in premature birth and postpartum endometritis; without ocular prophylaxis, 30 to 50 percent of exposed babies will develop GCON, a potentially blinding condition.

• Ocular prophylaxis at birth is a highly effective, simple and relatively inexpensive strategy to prevent 95 percent of GCON. This includes installation of 1 percent silver nitrate drops or 1 percent of tetracycline ointment in the eyes of the newborn within one hour after birth for all births both in the hospital and at home. Because of the high prevalence rates of gonorrhea in women and the low availability of effective treatment for GCON, this strategy is recommended for all areas of the developing world.

• Cases of neonatal conjunctivitis should always be considered gonococcal unless proven otherwise, and effective therapy (local and systemic) should be administered without delay to prevent damage to the eye.

• In addition to reducing GCON, controlling gonorrhea among pregnant women may also reduce GCON and also other maternal complications such as prematurity or postpartum infection. Although case finding strategies based on risk assessment seem promising, precise recommendations for the developing world cannot be made at this stage.

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