Here is the design of a clinical trial:

Official Title: Preventing Young Infant Infections Using Azithromycin in Labour (PreYIAL): a Blinded, Randomised, Placebo-controlled Trial

Included conditions:
- Bacterial Infections

Study Armgroups:
- {'label': 'Azithromycin', 'type': 'EXPERIMENTAL', 'description': 'A single 2g dose of Azithromycin', 'interventionNames': ['Drug: Azithromycin 500 mg Oral Tablet x 4']}
- {'label': 'Placebo', 'type': 'PLACEBO_COMPARATOR', 'description': 'Matching Placebo', 'interventionNames': ['Drug: Matching Placebo']}

Interventions:
- {'type': 'DRUG', 'name': 'Azithromycin 500 mg Oral Tablet x 4', 'description': 'A single prophylactic dose of antibiotic given during labour', 'armGroupLabels': ['Azithromycin']}
- {'type': 'DRUG', 'name': 'Matching Placebo', 'description': 'Matching Placebo', 'armGroupLabels': ['Placebo']}

Primary Outcomes:
- {'measure': 'Cumulative incidence of skin and soft tissue infection by 3 months of age in infants', 'description': 'Born to mothers receiving a single dose of 2g Azithromycin during labour. Assessed by history and physical examination at 7 days, 6 weeks and 3 months.', 'timeFrame': '3 months'}

Please estimate the sample size based on the assumption: 
90% power, two-sided alpha of 0.05, 5% dropout rate for SSTIs; 95% power, two-sided alpha of 0.05, no loss to follow-up for infant GBS carriage.
Sample size
        To detect a 50% decrease in SSTIs, from 6% in the controls to 3% in the intervention arm, with 90% power and a two-sided alpha of 0.05, a sample size of 1002 participants per arm is required. These assumptions were based on rates of impetigo in infants in Fiji and declines in skin infection in the Gambia following 2âg of oral azithromycin.19 22 This sample size was inflated to 1055 participants per arm (total n=2110) to allow for 5% dropout.39 44
        For the secondary outcome of bacterial infant carriage at 7âdays of age, 940 mother/infant pairs (470 per arm) will provide 95% power at a two-sided 0.05 alpha level to detect an 80% reduction in infant GBS carriage with the intervention, assuming 5% placebo group infant GBS carriage and no loss to follow-up. These assumptions were based on maternal carriage rates in Suva,45 an assumed 50% likelihood of GBS transfer to neonates from colonised mothers46 and carriage reduction levels found in the Gambian trial.20 This sample size will also detect reductions in the infant carriage rate for all relevant bacteria.