Azithromycin prevents pregnancy loss: reducing the level of tumor necrosis factor-alpha and raising the level of interleukin-10 in rats

Exposure to Macrolides During Pregnancy and the Risk for Spontaneous Abortions: A Population-Based Retrospective Cohort Study

Previous studies evaluating the risk of spontaneous abortions following exposure to macrolides reported controversial results. The goal of the current study was to examine the risk for spontaneous abortions following exposure to macrolides during pregnancy. We conducted a population-based retrospective cohort study by linking three computerized databases: Clalit Health Services drug dispensation database, Soroka Medical Center (SMC) birth database, and SMC hospitalizations database. Multivariate time-varying Cox regressions were performed and adjusted for suspected confounders and known risk factors for spontaneous abortions. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated. A secondary analysis was performed to assess the association between exposure to macrolides in terms of the defined daily dose dispensed and spontaneous abortions. The study cohort included 65,457 pregnancies that ended at Soroka Medical Center between 2004 and 2009, of which 6508 (9.9%) resulted in a spontaneous abortion. A total of 825 (1.26%) pregnancies were exposed to macrolides during the exposure period. Exposure to macrolides was not associated with spontaneous abortions as a group (adjusted HR 1.00 95% CI 0.77-1.31) or as specific medications. There was no evidence of a dose-response relationship between exposure to macrolides and spontaneous abortions. In conclusion, this population-based retrospective cohort study did not detect an increased risk for spontaneous abortion following exposure to macrolides during the first trimester of pregnancy.

Heme Oxygenase Protects against Placental Vascular Inflammation and Abortion by the Alarmin Heme in Mice

Both infectious as non-infectious inflammation can cause placental dysfunction and pregnancy complications. During the first trimester of human gestation, when palatogenesis takes place, intrauterine hematoma and hemorrhage are common phenomena, causing the release of large amounts of heme, a well-known alarmin. We postulated that exposure of pregnant mice to heme during palatogenesis would initiate oxidative and inflammatory stress, leading to pathological pregnancy, increasing the incidence of palatal clefting and abortion. Both heme oxygenase isoforms (HO-1 and HO-2) break down heme, thereby generating anti-oxidative and -inflammatory products. HO may thus counteract these heme-induced injurious stresses. To test this hypothesis, we administered heme to pregnant CD1 outbred mice at Day E12 by intraperitoneal injection in increasing doses: 30, 75 or 150 μmol/kg body weight (30H, 75H or 150H) in the presence or absence of HO-activity inhibitor SnMP from Day E11. Exposure to heme resulted in a dose-dependent increase in abortion. At 75H half of the fetuses where resorbed, while at 150H all fetuses were aborted. HO-activity protected against heme-induced abortion since inhibition of HO-activity aggravated heme-induced detrimental effects. The fetuses surviving heme administration demonstrated normal palatal fusion. Immunostainings at Day E16 demonstrated higher numbers of ICAM-1 positive blood vessels, macrophages and HO-1 positive cells in placenta after administration of 75H or SnMP + 30H. Summarizing, heme acts as an endogenous “alarmin” during pregnancy in a dose-dependent fashion, while HO-activity protects against heme-induced placental vascular inflammation and abortion.

Association of antibiotics therapy during pregnancy with spontaneous miscarriage: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis of observational studies were conducted to assess the association between antibiotics use during pregnancy and spontaneous miscarriage.

METHODS

A systematic search of online databases as well as reference lists of retrieved studies were performed up to September 2018 to identify observational studies that investigated the association between antibiotics use and spontaneous miscarriage. The retrieved studies were assessed for methodological quality. Pooled relative risk (RR) and 95% confidence intervals were calculated using DerSimonian and Laird method. Random-effects meta-analysis was used to account for conceptual heterogeneity. Sensitivity analysis was performed to assess the robustness of pooled estimates using Stata software.

RESULTS

Of 1435 retrieved studies, 89 were reviewed in depth and 12 (8 prospective cohort and 4 population-based case-control studies) met the criteria for inclusion in a systematic review with 1,084,792 participants and 7015 cases of spontaneous miscarriage. Finally, 11 studies were included in the meta-analysis (one study was not included in the meta-analysis owing to methodological issues and low-quality score). Overall percentage of miscarriage in women who received antibiotics was 2.6%. After adjusting for important potential confounders, use of macrolides (RR: 1.42; 95% CI 1.04, 1.93), quinolones (RR: 2.48; 95% CI 1.46, 4.20), and tetracyclines (RR: 2.57; 95% CI 1.95, 3.38) during pregnancy were significantly associated with spontaneous miscarriage. In macrolides class, a significant positive association was found between clarithromycin and spontaneous miscarriage (RR: 1.98; 95% CI 1.46, 2.70). Sensitivity analysis demonstrated the consistency of the results, indicating that the meta-analysis model was robust.

CONCLUSION

Findings support a significant positive association between use of macrolides (especially clarithromycin), quinolones, and tetracyclines during pregnancy and spontaneous miscarriage, although it should be interpreted with caution in the context of limitations of the available data.

REVIEW REGISTRATION

International register for systematic reviews; PROSPEROCRD42018093465.

Metagenomic Analysis of Antibiotic-Induced Changes in Gut Microbiota in a Pregnant Rat Model

Food and Drug Administration (FDA, USA)-approved category B antibiotics are commonly prescribed to treat infections during pregnancy. The aim of this study was to investigate antibiotic-induced changes in gut microbiota (GM) that occur during pregnancy. The 16S rRNA amplicon deep-sequencing method was used to analyze the effect of category B antibiotics (azithromycin, amoxicillin and cefaclor) on GM during pregnancy using a rat model. The GM composition was substantially modulated by pregnancy and antibiotics administration. Firmicutes, Bacteroidetes, Proteobacteria, Chlamydiae, Actinobacteria, and Cyanobacteria were the dominant phyla. Antibiotic treatment during pregnancy increased the relative abundance of Proteobacteria and reduced Firmicutes. The genera Shigella, Streptococcus, Candidatus Arthromitus, and Helicobacter were significantly (p < 0.05) more abundant during pregnancy. Antibiotics significantly (p < 0.05) reduced the relative abundance of Lactobacillus but increased that of Enterobacter. There was a significant (p < 0.05) decrease in Lactobacillus sp., Lactobacillus gallinarum and Lactobacillus crispatus during pregnancy. Antibiotic treatment reduced bacterial diversity; the lowest number of operational taxonomic units (OTUs) were detected in the cefaclor-treated groups. Antibiotics significantly (p < 0.05) promoted weight gain during pregnancy, and increased relative abundance of Shigella sonnei, Enterococcus hormaechei, and Acinetobacter sp. GM perturbations were accompanied by increases in Proteobacteria abundance and weight gain in pregnancy following antibiotic treatment.