Double intrauterine insemination (IUI) showed no clear difference in miscarriage ratea compared with single IUI (low certainty).
The review found no eligible studies for this question.
The review found no eligible studies for this question.
It is very uncertain whether intramuscular (IM) progesterone changes miscarriage rate compared with vaginal progesterone (very low certainty).
It is very uncertain whether subcutaneous (Sc) gonadotropin‐releasing hormone (GnRH) agonist changes miscarriage rate compared with placebo/no treatment (very low certainty).
It is very uncertain whether early hCG changes miscarriage rate compared with late hCG (very low certainty).
Aromatase inhibitors showed no clear difference in miscarriage rate per couple compared with anti‐oestrogens (low certainty).
It is very uncertain whether gonadotropins with GnRH agonists changes miscarriage rate per couple compared with gonadotropins alone (very low certainty).
Gonadotropins with GnRH antagonist showed no clear difference in miscarriage rate per couple compared with gonadotropins alone (low certainty).
Aromatase inhibitors may leads to lower miscarriage rate per couple compared with gonadotropins (low certainty).
It is very uncertain whether aromatase inhibitors with gonadotropins changes miscarriage rate per couple compared with anti‐oestrogens with gonadotropins (very low certainty).
Gonadotropins showed no clear difference in miscarriage rate per couple compared with anti‐oestrogens (low certainty).
It is very uncertain whether gradient technique changes miscarriage rate per couple compared with wash and centrifugation (very low certainty).
It is very uncertain whether swim‐up technique changes miscarriage rate per couple compared with gradient technique (very low certainty).
It is very uncertain whether hCG changes miscarriage rate per pregnancy compared with gnRH‐a (very low certainty).
It is very uncertain whether u‐hCG changes miscarriage rate per pregnancy compared with r‐hCG (very low certainty).
It is very uncertain whether oral progesterone changes miscarriage rate per clinical pregnancy compared with vaginal progesterone (very low certainty).
It is very uncertain whether short interval changes miscarriage rate per pregnancy ‐ 24 hours versus 34 to 36 hours compared with long interval (very low certainty).