Although diagnosis of infection in pregnancy is critically important, symptoms of infection in prenatal patients may be absent or difficult to detect or interpret. Many infectious etiologies are asymptomatic. Syphilis, latent-phase herpes, HIV, and others may be present without producing any symptoms in the pregnant patient. For these conditions, routine screening is recommended for all pregnant patients by history, physical examination, and/or diagnostic studies.

Some disease processes produce characteristic symptoms, which should be further evaluated whenever present. Such symptoms as fever, chills, bleeding per vagina, severe abdominal pain, or dysuria should lead to prompt evaluation. For other disease processes, the symptoms associated with infection may be difficult to interpret or may be masked by some of the common symptoms associated with pregnancy. Cervical mucus production may be increased during pregnancy and some women may interpret this increased mucus as infectious in cause. By contrast, some women may interpret an abnormal vaginal discharge as “normal” for pregnancy, delaying evaluation or failing to mention such symptoms during the course of prenatal care. Nonspecific abdominal pain is also a relatively common symptom occurring during pregnancy. Providers should be diligent in eliciting suggestive symptoms and should maintain a low threshold for following up such symptoms with appropriate diagnostic tests. As a general rule, women should be screened by history for symptoms that are suggestive of common infectious complications of pregnancy at each prenatal visit. Those patients who report such symptoms should be further evaluated for the possible presence of infection (Table 13.1).

The primary concern in pregnancy is with the health and welfare of the mother. Timely diagnosis and treatment of infection has direct health consequences for the mother and should be approached in the same manner as in nonpregnant patients. Routine prenatal care includes screening for gonorrhea, chlamydia, syphilis, HIV, hepatitis B, and urine culture for bacteriuria. These tests are performed in all patients regardless of symptoms. It is worth noting that most of these infections are sexually transmitted. Pregnancy can be taken as good evidence of unprotected sexual activity and therefore confers the infection risk associated with unprotected sex. Prenatal patients are also routinely screened for evidence of human papilloma virus through Pap smear screening. Although treatment is generally deferred until the patient is no longer pregnant, documentation of the presence and severity of dysplastic lesions is an important element of the comprehensive care plan. The timing and method of screening for these infectious conditions are reviewed in Chap. 3.

Patients with suggestive symptoms may also be screened for other infectious conditions. Patients with vaginal discharge should be evaluated for the presence of bacterial vaginosis and trichomoniasis in addition to gonorrhea and chlamydia. The presence of bacterial vaginosis has been associated with an increased risk of preterm contractions and preterm labor. Treatment of bacterial vaginosis or trichomoniasis is recommended after the first trimester. Patients with urinary symptoms such as dysuria or hematuria should be evaluated for possible urinary tract infection (UTI).