Lyme Disease in Pregnancy: What Studies Show About Outcomes
Can Lyme disease affect pregnancy?
A study followed over 300 treated women.
Outcomes were mostly reassuring—but not fully clear.
Lyme disease pregnancy outcomes remain an important concern for women diagnosed with infection during pregnancy.
This question often comes up when a patient is diagnosed with Lyme disease during pregnancy and wants to understand the risks for both mother and baby.
A study by Maraspin and colleagues examined pregnancy outcomes in 304 women treated for early Lyme disease presenting with erythema migrans.
Quick Answer: Does Lyme Disease Affect Pregnancy Outcomes?
In treated early Lyme disease, most pregnancy outcomes were similar to the general population.
However, a subset of patients experienced complications, and the long-term impact remains uncertain.
What the Study Found
All women in the study were diagnosed with Lyme disease based on an erythema migrans rash and were treated with antibiotics.
Most received intravenous ceftriaxone, while others were treated with penicillin-based regimens.
Patients were followed through pregnancy and for up to 18 months afterward.
Pregnancy Outcomes After Lyme Disease Treatment
Unfavorable outcomes occurred in 13.8% of pregnancies.
- 22 preterm births
- 10 fetal or perinatal deaths
- 15 congenital anomalies
However, several of these cases had other possible contributing factors.
Overall, the rate of complications was not significantly higher than in the general population.
What Other Research Shows
A separate study of approximately 2,000 women with a history of Lyme disease did not find increased risk of:
- Fetal death
- Low birth weight
- Shortened pregnancy duration
However, a history of tick bite before pregnancy was associated with congenital abnormalities in some cases.
Why These Findings Matter
This research provides some reassurance—but does not fully answer all questions.
Importantly, the study focused only on women treated for early Lyme disease.
It did not address untreated infection or long-term developmental outcomes in children.
For broader symptom patterns, see Lyme disease symptoms guide.
Limitations of the Study
Several limitations affect how the findings should be interpreted:
- No comparison with untreated Lyme disease
- No long-term follow-up of children
- Potential confounding factors in adverse outcomes
Because of these limitations, uncertainty remains.
Clinical Perspective
This study suggests that early treated Lyme disease during pregnancy is often associated with favorable outcomes.
However, it also highlights important gaps in knowledge.
Questions remain about untreated infection, timing of treatment, and long-term developmental effects.
Understanding infection patterns across populations—including children—is critical.
These findings also relate to broader questions about persistent Lyme disease mechanisms.
Clinical Takeaway
Most women treated for early Lyme disease during pregnancy have outcomes similar to the general population.
However, uncertainty remains—particularly regarding untreated infection and long-term outcomes—highlighting the need for careful evaluation and follow-up.
References
- Maraspin V et al. Course and Outcome of Erythema Migrans in Pregnant Women. J Clin Med. 2020.
- Strobino BA et al. Lyme disease and pregnancy outcome. Am J Obstet Gynecol. 1993.
Related Articles
- Two mothers transmit Babesia to their babies
- Congenital babesiosis case reports
- Treating tick bites during pregnancy
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
