McCormack 1987.

Methods	Design: randomised, placebo‐controlled, 3‐armed trial
Participants	Number assigned: 825 women (macrolide arm 1, n = 174; macrolide arm 2, n = 224; placebo, n = 427) Age in years: N/A Setting: secondary care
Interventions	Indication: pregnant women harbouring genital Ureaplasma urealyticum or Mycoplasma hominis, or both Type of macrolide: arm 1: erythromycin estolate, arm 2: erythromycin stearate Route: per oral Dose per day: 1000 mg (both arms) Duration of treatment: 6 weeks (both arms) Total treatment dose: 42,000 mg (both arms)
Outcomes	Adverse events stated as an outcome in trial registration/protocol/paper: unclear Adverse events ascertainment: participant asked + clinical examination/lab tests Adverse events: data reported Antimicrobial resistance: not reported Death: not reported
Funding sources	Study supported by the National Institute of Child Health and Human Development.
Notes	Concomitant medication: unclear Note: type of erythromycin used is changed roughly halfway through the study period (stearate to estolate) due to the reporting of many adverse events.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Sequence generation not described.
Allocation concealment (selection bias)	Unclear risk	Allocation not described.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Identical‐appearing placebo
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Pregnant women and clinicians blinded.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Large dropout in all 3 groups ‐ only about 40% of women completed the study. However, adverse events presented for 91% of participants.
Selective reporting (reporting bias)	Low risk	Adverse events not clearly stated as an outcome. Standardised ascertainment and adverse events reported.
Other bias	Low risk	None were identified.