Metformin may leads to lower live birth rate per woman ‐ short protocol GnRH‐antagonist compared with placebo or no treatment (low certainty).
Metformin may leads to lower incidence of OHSS per woman compared with placebo or no treatment (low certainty).
Metformin may leads to higher clinical pregnancy rate per woman ‐ long protocol GnRH‐agonist compared with placebo or no treatment (low certainty).
Metformin may leads to higher side effects per woman compared with placebo or no treatment (low certainty).
Metformin showed no clear difference in live birth rate per woman compared with placebo or no treatment (low certainty).
Metformin showed no clear difference in miscarriage rate per woman aParticipants with BMI < 30 kg/2 compared with clomiphene citrate (low certainty).
Metformin showed no clear difference in miscarriage rate per woman aParticipants with BMI ≥ 30 kg/m2 compared with clomiphene citrate (low certainty).
Metformin probably leads to higher adverse events (gastrointestinal) per woman compared with placebo or no treatment (moderate certainty).
Metformin may leads to higher ovulation rate per woman compared with placebo or no treatment (low certainty).
Metformin showed no clear difference in live birth rate per woman compared with placebo or no treatment (low certainty).
The review found no eligible studies for this question.
Metformin probably leads to higher adverse events (gastrointestinal) per woman compared with placebo or no treatment (moderate certainty).
It is very uncertain whether metformin changes miscarriage rate per woman compared with clomiphene citrate (very low certainty).
Metformin probably leads to higher clinical pregnancy rate per woman compared with placebo or no treatment (moderate certainty).
Metformin may leads to higher menstrual frequency per woman compared with placebo or no treatment (low certainty).
Metformin probably leads to higher ovulation rate per woman compared with placebo or no treatment (moderate certainty).
Metformin showed no clear difference in miscarriage rate per woman compared with placebo or no treatment (low certainty).
Metformin may leads to higher live birth rate (per woman) compared with placebo co‐treatment (low certainty).
Metformin showed no clear difference in multiple pregnancy rate (per woman) compared with placebo co‐treatment (low certainty).
Metformin may leads to higher ongoing pregnancy rate (per woman) compared with placebo co‐treatment (low certainty).