Comparison 4. Recurrent miscarriage: Vaginal micronized progesterone versus placebo.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
4.1 Live birth	1	826	Risk Ratio (M‐H, Fixed, 95% CI)	1.04 [0.94, 1.15]
4.2 Miscarriage (defined as delivery before 24 weeks of gestation)	1	826	Risk Ratio (M‐H, Fixed, 95% CI)	0.96 [0.79, 1.17]
4.3 Preterm birth (defined as birth before 37 weeks of gestation)	1	533	Risk Ratio (M‐H, Fixed, 95% CI)	1.12 [0.67, 1.87]
4.4 Stillbirth	1	826	Risk Ratio (M‐H, Fixed, 95% CI)	0.54 [0.05, 5.91]
4.5 Ectopic pregnancy	1	826	Risk Ratio (M‐H, Fixed, 95% CI)	0.92 [0.31, 2.72]
4.6 Congenital abnormalities	1	542	Risk Ratio (M‐H, Fixed, 95% CI)	0.75 [0.31, 1.85]
4.7 Adverse drug events	1	836	Risk Ratio (M‐H, Fixed, 95% CI)	1.46 [0.93, 2.29]
4.8 Live birth (subgrouped by maternal age)	1		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
4.8.1 Maternal age < 35 years	1	558	Risk Ratio (M‐H, Fixed, 95% CI)	1.04 [0.92, 1.18]
4.8.2 Maternal age ≥ 35 years	1	268	Risk Ratio (M‐H, Fixed, 95% CI)	1.04 [0.87, 1.25]