What is the recommended management of rubella infection in a pregnant woman?

Management of Rubella Infection During Pregnancy

There is no specific treatment available to prevent or cure rubella infection during pregnancy; management focuses on supportive care for maternal symptoms, serologic confirmation of infection, detailed prenatal counseling about fetal risks based on gestational age, and close monitoring for congenital rubella syndrome. 1, 2

Immediate Diagnostic Confirmation

When rubella infection is suspected during pregnancy, the diagnosis must be confirmed serologically because clinical diagnosis alone is unreliable:

• Obtain rubella-specific IgM antibody testing, which is most reliable when collected between 1-2 weeks after rash onset 1
• Consider paired sera testing with acute-phase serum collected as soon as possible after symptom onset and convalescent-phase serum collected 10 or more days later; a four-fold rise in IgG titer confirms infection 1
• Do not rely on clinical presentation alone, as rubella-like illness can be caused by other viral infections 3

Why No Specific Treatment Exists

Immune globulin (IG) is NOT recommended for post-exposure prophylaxis or treatment because it will not prevent infection or viremia, and may only modify or suppress symptoms, creating a false sense of security. 4, 1

• IG has not been proven effective in preventing congenital rubella syndrome 1
• Infants with congenital rubella have been born to women who received IG shortly after exposure 4
• No antiviral medications or other specific therapies are available to prevent vertical transmission or fetal damage 2

Maternal Supportive Care

Provide symptomatic management for maternal complications:

• Monitor for thrombocytopenia (occurs in 1 per 3,000 cases) and encephalitis (1 per 6,000 cases), which are more common in adults 1
• Manage joint symptoms (arthralgia/arthritis), which occur in up to 70% of infected adult women and typically resolve spontaneously within 1 day to 3 weeks 1
• These complications require only supportive care as no specific interventions alter their course 1

Critical Prenatal Counseling Based on Gestational Age

The risk of congenital defects depends critically on gestational age at infection, and this information must be communicated clearly to the patient:

• Up to 85% risk of congenital defects when infection occurs in the first 8 weeks of gestation 1
• Greater than or equal to 20% risk of congenital rubella syndrome (CRS) during the first trimester overall 4
• Risk declines to 10-24% when infection occurs between 13-16 weeks 1
• Defects are rarely noted when infection occurs after the 16th week of gestation 3
• At 29 weeks gestation, the risk of CRS is significantly lower than in the first trimester, though maternal infection remains concerning 1

Fetal Monitoring and Prenatal Diagnosis

Maternal infection does not indicate vertical transmission in 100% of cases, and fetal damage does not necessarily occur in all cases of fetal infection, making adequate prenatal diagnostic workup mandatory:

• Advanced prenatal diagnostic techniques should be offered to distinguish cases without fetal damage 2
• Detection of rubella-specific IgM antibodies in fetal blood through amniocentesis can help establish the diagnosis prenatally and aid in management 3
• Serial ultrasound examinations should be performed to monitor for manifestations of CRS 5

Manifestations of Congenital Rubella Syndrome to Monitor

The classic triad includes auditory, cardiac, and ophthalmic manifestations:

• Sensorineural deafness is the most common manifestation 1
• Cardiac defects (patent ductus arteriosus, pulmonary stenosis) 1
• Ophthalmic abnormalities (congenital cataracts, glaucoma) 1, 6
• Neurologic defects including microcephaly, meningoencephalitis, and mental retardation 1
• Intrauterine growth retardation, hepatosplenomegaly, thrombocytopenia, and radiolucent bone defects 1
• Delayed manifestations including diabetes mellitus, thyroid disease, and progressive panencephalitis may develop later, necessitating long-term follow-up 3

Pregnancy Termination Counseling

Pregnancy termination should not be routinely recommended based solely on confirmed maternal infection—adequate prenatal counseling and diagnostic workup are mandatory. 1

• The decision must be individualized based on gestational age at infection, confirmed fetal infection status, and ultrasound findings 2
• Prevention of voluntary interruption of pregnancy is mandatory in cases without fetal damage or in cases of maternal false IgM positivity 2
• The risk of vaccine-associated defects (0% to 1.6%) is negligible and should not ordinarily be a reason to consider interruption of pregnancy if inadvertent vaccination occurred 4

Essential Postpartum Management

Women who remain rubella-seronegative postpartum must receive immediate MMR vaccination before hospital discharge to prevent congenital rubella syndrome in future pregnancies. 1

• Postpartum vaccination of all women not known to be immune could prevent approximately 40% of CRS cases 1
• Vaccination must occur before discharge because follow-up vaccination programs have proven less successful than immediate postpartum administration 1
• Counsel the patient to avoid pregnancy for 3 months (28 days minimum) following vaccination 1
• Breastfeeding is NOT a contraindication to vaccination, even though virus may be excreted in breast milk 1

Common Pitfalls to Avoid

• Do not administer IG thinking it will prevent infection or CRS—it creates false reassurance without proven benefit 4, 1
• Do not delay postpartum vaccination until a clinic visit; vaccinate before hospital discharge 1
• Do not withhold vaccination due to breastfeeding concerns 1
• Do not recommend routine pregnancy termination without complete diagnostic workup and counseling 1, 2
• Do not assume all infected fetuses will have severe defects; vertical transmission and fetal damage are not universal 2