A Cochrane review included 1 study with a total of 140 subjects. A second well-conducted trial was excluded because of high (30.5%) losses to follow-up. Tetracycline 500 mg four times daily for one week and evacuation was compared with evacuation. No differences were detected in postabortal infection rates with routine prophylaxis or control (RR 1.36, 95 % CI 0.86 to 2.14). However, compliance with antibiotic treatment was also low. Only 17.4% took the capsules and even then, failed to follow the instructions properly.
Comment: The quality of evidence is downgraded by study quality (poor compliance; only 17.4% took the antibiotic capsules) and by imprecise results (limited study size for comparison).