Lyme Disease and Pregnancy: Findings from an 11-Patient Case Series

Lyme disease and pregnancy remain areas where clinical evidence is limited but important for maternal and fetal care. A case series of pregnant women with Lyme borreliosis (LB) provides insight into possible outcomes and treatment approaches.

The first confirmed case of Lyme borreliosis in pregnancy was described in 1985 in a 28-year-old woman infected during the first trimester who delivered at 35 weeks, according to Schlesinger et al.²

“The mother developed symptoms consistent with LB post-delivery as documented by a positive immunofluorescence assay for LB. Unfortunately, the child died of congenital heart disease, and the autopsy revealed spirochetes infiltrating the spleen, kidneys, and bone marrow, but not cardiac tissue,” the authors wrote.

Complications of maternal Lyme borreliosis during pregnancy have been reported, including stillbirth and possible congenital malformations, according to Trevisan et al.

They also noted that Borrelia-specific antibodies have been detected in the cerebrospinal fluid of an infant with documented neurologic dysfunction.

“Pregnant women are considered a vulnerable group due to a weakened immune system. Therefore, they are more susceptible to infection with an increased risk for severe illness—and infections in pregnant women carry the added risk of potential infection in the developing fetus.”¹

Case Series: Lyme Disease During Pregnancy

The study included 11 pregnant women diagnosed with Lyme disease at different stages of pregnancy:

• 5 women diagnosed during the first trimester
• 3 women diagnosed during the second trimester
• 3 women diagnosed during the third trimester

Clinical Presentation

The women presented with a range of symptoms during pregnancy:

• 6 developed erythema migrans between week 8 and week 34
• 3 had myoarticular involvement
• 1 had neurological symptoms

Two women had positive serology for Lyme borreliosis but did not develop clinical symptoms. All other patients were seropositive except for one 26-year-old woman with erythema migrans.

Treatment During Pregnancy

All mothers were treated with amoxicillin 1 g three times daily for 14 days.

Pregnancy Outcomes

Most pregnancies resulted in healthy outcomes:

• One infant was born prematurely at 7 months
• One infant developed angiomatoid skin patches that resolved spontaneously after 18 months
• All other infants were born healthy

At one-year follow-up, 10 of the women remained healthy. One woman with articular and neurological symptoms improved partially with amoxicillin but required intravenous ceftriaxone because of persistent symptoms.

Authors’ Conclusions

• In pregnant women living in endemic areas, testing for Borrelia antibodies should be considered, with possible testing of umbilical cord blood at delivery if maternal testing is positive.
• Pregnant women with Lyme borreliosis should receive treatment and careful clinical follow-up, particularly for cutaneous, myoarticular, neurological, ocular, and cardiac manifestations, which may warrant fetal echocardiography.
• Newborns should be evaluated for possible clinical manifestations, as infants born to mothers with gestational Lyme borreliosis have occasionally been reported to be small for gestational age or to present with findings such as pyloric stenosis, cutaneous eruptions, angiomas, neurological disorders, muscle hypotonia, hypospadias, or skeletal abnormalities.

Editor’s note: Although this case series reported largely favorable outcomes, larger studies of Lyme disease and pregnancy would help clarify risks. Long-term follow-up may also be important to evaluate possible later sequelae such as neurodevelopmental disorders.

Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.

Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention