Lyme Disease in Pregnancy: What Studies Show About Outcomes
Lyme disease during pregnancy raises concerns about maternal and fetal health
Treatment timing and early recognition may influence outcomes
Evidence remains limited despite growing research
The study by researchers in Slovenia looked at the potential effects of Lyme disease in pregnancy on pregnancy outcomes. In their article, “Course and Outcome of Erythema Migrans in Pregnant Women,” Maraspin and colleagues describe pregnancy course and outcome for 304 women who were treated with antibiotics for early Lyme disease.
Patients often ask whether Lyme disease in pregnancy affects fetal outcomes, whether treatment is safe, and what happens after a tick bite while pregnant. These questions remain clinically important because research is still limited.
All of the women had been diagnosed with Lyme disease based upon the presence of an erythema migrans (EM or bull’s-eye) rash. They were evaluated before antibiotic treatment was initiated, then 2 weeks later, followed by 2, 6, 12 and 18-month follow-ups.
At the first visit, the majority (98%) of patients were treated with IV ceftriaxone (2 g once daily). The remaining patients received either IV penicillin G (10,000,000 units twice daily), or oral phenoxymethylpenicillin (1 g 3 times daily). Patients received a 14-day course of antibiotics.
Pregnancy Outcomes Following Lyme Disease Treatment
The outcome of pregnancy was unfavorable in 13.8% (42/304) of patients, the authors report.
There were 22 preterm births, 10 fetal/perinatal deaths, and 15 anomalies. However, several mothers had potential explanations for their unfavorable pregnancy outcomes.
The poor outcome for Lyme disease patients was not significantly different when compared to the general population. Still, they warn, “multivariable analyses showed that patients who develop EM in the early stages of pregnancy might have a higher risk of unfavorable outcome.”
The authors concluded that pregnancy outcome was generally favorable with 2 weeks of treatment with IV ceftriaxone.
The outcomes for mothers remained concerning based on rates of preterm birth, fetal/perinatal death, and anomalies, though causation remains uncertain.
What Studies Suggest About Lyme Disease and Pregnancy Risk
Meanwhile, another study of 2,000 women with a history of Lyme disease did not demonstrate an increased risk of fetal death, decreased birth weight, or length of gestation at delivery. In the same study of 2,000 women, a history of a tick bite within 3 years of conception was associated with congenital defects.
Research into Lyme disease during pregnancy remains limited because many studies involve treated early Lyme disease rather than untreated infection or long-term follow-up.
Women with Lyme disease during pregnancy may also have questions about diagnostic timing and treatment decisions following tick exposure. Learn more about tick bites during pregnancy.
Editor’s Perspective
The authors enrolled women with early Lyme disease. Maraspin and colleagues did not follow the 262 women who gave birth with favorable outcomes for long-term developmental problems. Nor did the authors describe outcomes for women who were not treated for early Lyme disease.
The findings were based on a case series. Hopefully, their conclusions encourage additional research examining whether Lyme disease contributed to even one preterm birth, fetal/perinatal death, or anomaly in pregnant women.
Frequently Asked Questions
Can Lyme disease during pregnancy affect the baby?
Research remains limited. Some studies suggest generally favorable outcomes with treatment, though questions remain regarding untreated infection and early pregnancy exposure.
Is Lyme disease treatment safe during pregnancy?
Treatment decisions depend on timing, symptoms, and antibiotic selection. Pregnant patients should discuss treatment options carefully with their clinicians.
What happens after a tick bite during pregnancy?
Pregnant patients with tick bites should discuss symptoms, timing of exposure, and potential evaluation with their healthcare professional.
Can Lyme disease affect fertility?
Current evidence regarding Lyme disease and fertility remains limited. Most available studies focus on pregnancy outcomes rather than infertility itself.
Does early treatment improve pregnancy outcomes?
The available evidence suggests treatment may improve outcomes, though more research is needed regarding timing and long-term follow-up.
Clinical Takeaway
Research examining Lyme disease in pregnancy remains limited despite increasing interest in maternal and fetal outcomes.
Early recognition, appropriate treatment, and additional research remain important for understanding Lyme disease during pregnancy.
Related Articles
These related articles explore pregnancy, congenital transmission, diagnostic delays, and related tick-borne concerns.
Two mothers transmit Babesia to their babies
Congenital transmission of babesiosis
Delayed Lyme disease diagnosis
Lyme coinfections
Recovery from Lyme disease
References
- Maraspin V, Lusa L, Blejec T, Ruzic-Sabljic E, Pohar Perme M, Strle F. Course and Outcome of Erythema Migrans in Pregnant Women. J Clin Med. 2020;9(8).
- Strobino BA, Williams CL, Abid S, Chalson R, Spierling P. Lyme disease and pregnancy outcome: a prospective study of two thousand prenatal patients. Am J Obstet Gynecol. 1993;169(2 Pt 1):367-374.
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
