Table 1 Inclusion and exclusion criteria in examination of studies

1. Diagnosis of PCOS accordance with to the NIH, Rotterdam or AES criteria.

1. Studies that included women with preexisting diabetes mellitus or Hypertension.

2. Use of women without PCOS as controls.

2. Metformin was used by the PCOS group after conception.

3. End points include GDM, PIH, PE, preterm, birth weight, caesarean section or admission to NICU.

3. Multiple pregnancy rate was significantly different in the two groups.