Use of antibiotics during pregnancy and risk of spontaneous abortion
- PMID: 28461374
- PMCID: PMC5415390
- DOI: 10.1503/cmaj.161020
Use of antibiotics during pregnancy and risk of spontaneous abortion
Abstract
Background: Although antibiotics are widely used during pregnancy, evidence regarding their fetal safety remains limited. Our aim was to quantify the association between antibiotic exposure during pregnancy and risk of spontaneous abortion.
Methods: We conducted a nested case-control study within the Quebec Pregnancy Cohort (1998-2009). We excluded planned abortions and pregnancies exposed to fetotoxic drugs. Spontaneous abortion was defined as having a diagnosis or procedure related to spontaneous abortion before the 20th week of pregnancy. The index date was defined as the calendar date of the spontaneous abortion. Ten controls per case were randomly selected and matched by gestational age and year of pregnancy. Use of antibiotics was defined by filled prescriptions between the first day of gestation and the index date and was compared with (a) non-exposure and (b) exposure to penicillins or cephalosporins. We studied type of antibiotics separately using the same comparator groups.
Results: After adjustment for potential confounders, use of azithromycin (adjusted odds ratio [OR] 1.65, 95% confidence interval [CI] 1.34-2.02; 110 exposed cases), clarithromycin (adjusted OR 2.35, 95% CI 1.90-2.91; 111 exposed cases), metronidazole (adjusted OR 1.70, 95% CI 1.27-2.26; 53 exposed cases), sulfonamides (adjusted OR 2.01, 95% CI 1.36-2.97; 30 exposed cases), tetracyclines (adjusted OR 2.59, 95% CI 1.97-3.41; 67 exposed cases) and quinolones (adjusted OR 2.72, 95% CI 2.27-3.27; 160 exposed cases) was associated with an increased risk of spontaneous abortion. Similar results were found when we used penicillins or cephalosporins as the comparator group.
Interpretation: After adjustment for potential confounders, use of macro-lides (excluding erythromycin), quinolones, tetracyclines, sulfonamides and metronidazole during early pregnancy was associated with an increased risk of spontaneous abortion. Our findings may be of use to policy-makers to update guidelines for the treatment of infections during pregnancy.
© 2017 Canadian Medical Association or its licensors.
Conflict of interest statement
Competing interests: Anick Bérard is a consultant for plaintiffs in litigations involving antidepressants and birth defects. No other competing interests were declared.
Figures


Comment in
-
Underlying maternal infection likely cause of study findings.CMAJ. 2017 Jul 10;189(27):E918. doi: 10.1503/cmaj.733199. CMAJ. 2017. PMID: 28694313 Free PMC article. No abstract available.
-
The authors respond to "Underlying maternal infection likely cause of study findings".CMAJ. 2017 Jul 10;189(27):E919. doi: 10.1503/cmaj.733254. CMAJ. 2017. PMID: 28694314 Free PMC article. No abstract available.
-
Optimal levels of DHEA for pregnancy may be reduced by antibiotics.CMAJ. 2017 Jul 31;189(30):E999. doi: 10.1503/cmaj.733105. CMAJ. 2017. PMID: 28760838 Free PMC article. No abstract available.
-
The authors respond to: "Optimal levels of DHEA for pregnancy may be reduced by antibiotics".CMAJ. 2017 Jul 31;189(30):E1000. doi: 10.1503/cmaj.733133. CMAJ. 2017. PMID: 28760839 Free PMC article. No abstract available.
-
Maternal infection can cause spontaneous abortion.CMAJ. 2017 Aug 8;189(31):E1021. doi: 10.1503/cmaj.733203. CMAJ. 2017. PMID: 28790059 Free PMC article. No abstract available.
-
Response to: "Maternal infection can cause spontaneous abortion".CMAJ. 2017 Aug 8;189(31):E1022. doi: 10.1503/cmaj.733251. CMAJ. 2017. PMID: 28790060 Free PMC article. No abstract available.
References
-
- Bar-Oz B, Diav-Citrin O, Shechtman S, et al. Pregnancy outcome after gestational exposure to the new macrolides: a prospective multi-center observational study. Eur J Obstet Gynecol Reprod Biol 2008;141:31–4. - PubMed
-
- Bar-Oz B, Weber-Schoendorfer C, Berlin M, et al. The outcomes of pregnancy in women exposed to the new macrolides in the first trimester: a prospective, multicentre, observational study. Drug Saf 2012;35:589–98. - PubMed
-
- Einarson A, Phillips E, Mawji F, et al. A prospective controlled multicentre study of clarithromycin in pregnancy. Am J Perinatol 1998;15:523–5. - PubMed
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Other Literature Sources
Medical