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Each row is one question a systematic review asked: who, what, compared with what, and which outcome, with the effect it found and how certain that is. Words match anywhere in the field.
2,653 questions in 194 reviews · Gynaecology and Fertility
current versionsNo studies 531 · 20%Ungraded 76 · 2.9%Very low 826 · 31.1%Low 855 · 32.2%Moderate 341 · 12.9%High 24 · 0.9%
Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Coasting vs early unilateral follicular aspiration Multiple pregnancy · Women undergoing assisted reproduction Coasting (withholding gonadotrophins) for preventing ovarian hyperstimulation syndrome (2017) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs placebo or no treatment Live birth rate per woman · women with polycystic ovary syndrome, oligo amenorrhoea and subfertility Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 1.59 [1, 2.51] | 4 studies · 435 participants | Low |
Metformin combined with clomiphene citrate vs clomiphene citrate alone Menstrual frequency per woman · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | no estimate extracted | NR | No studies |
Metformin combined with clomiphene citrate vs clomiphene citrate alone Ovulation rate per woman · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 1.57 [1.28, 1.92] | 21 studies · 1624 participants | Moderate |
Metformin combined with clomiphene citrate vs clomiphene citrate alone Miscarriage rate per woman · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 1.59 [1.03, 2.46] | 9 studies · 1096 participants | Low |
Metformin vs clomiphene citrate Live birth rate per woman Participants with BMI < 30 kg/m2 or ≤ 32 kg/m2a · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 1.71 [1, 2.94] | 3 studies · 241 participants | Very low |
Metformin vs clomiphene citrate Live birth rate per woman Participants with BMI ≥ 30 kg/m2a · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 0.3 [0.17, 0.52] | 2 studies · 500 participants | Very low |
Metformin vs clomiphene citrate Adverse events (gastrointestinal) · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs clomiphene citrate Clinical pregnancy rate per woman Participants with BMI < 30 kg/m2 or ≤ 32 kg/m2a · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 1.56 [1.05, 2.33] | 5 studies · 490 participants | Very low |
Metformin vs clomiphene citrate Clinical pregnancy rate per woman Participants with BMI ≥ 30 kg/m2a · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 0.34 [0.21, 0.55] | 2 studies · 500 participants | Very low |
Metformin vs clomiphene citrate Menstrual frequency · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs clomiphene citrate Ovulation rate per woman Participants with BMI < 30 kg/m2b · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 0.81 [0.51, 1.28] | 4 studies · 312 participants | Low |
Metformin vs placebo or no treatment Adverse events (gastrointestinal) per woman · women with polycystic ovary syndrome, oligo amenorrhoea and subfertility Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 4.76 [3.06, 7.41] | 7 studies · 670 participants | Moderate |
Metformin vs clomiphene citrate Ovulation rate per woman Participants with BMI ≥ 30 kg/m2b · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 0.29 [0.2, 0.43] | 2 studies · 500 participants | Low |
Metformin vs clomiphene citrate Miscarriage rate per woman · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 0.92 [0.5, 1.67] | 5 studies · 741 participants | Very low |
Metformin vs placebo or no treatment Clinical pregnancy rate per woman · women with polycystic ovary syndrome, oligo amenorrhoea and subfertility Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 1.93 [1.42, 2.64] | 9 studies · 1027 participants | Moderate |
Metformin vs placebo or no treatment Menstrual frequency per woman · women with polycystic ovary syndrome, oligo amenorrhoea and subfertility Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 1.72 [1.14, 2.61] | 7 studies · 427 participants | Low |
Metformin vs placebo or no treatment Ovulation rate per woman · women with polycystic ovary syndrome, oligo amenorrhoea and subfertility Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 2.55 [1.81, 3.59] | 14 studies · 701 participants | Moderate |
Metformin vs placebo or no treatment Miscarriage rate per woman · women with polycystic ovary syndrome, oligo amenorrhoea and subfertility Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 1.08 [0.5, 2.35] | 4 studies · 748 participants | Low |
Metformin combined with clomiphene citrate vs clomiphene citrate alone Live birth rate per woman · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 1.21 [0.92, 1.59] | 9 studies · 1079 participants | Low |
Metformin combined with clomiphene citrate vs clomiphene citrate alone Adverse events (gastrointestinal) per woman · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 3.97 [2.59, 6.08] | 3 studies · 591 participants | Moderate |
Metformin combined with clomiphene citrate vs clomiphene citrate alone Clinical pregnancy rate per woman · women with polycystic ovary syndrome Insulin‐sensitising drugs (metformin, rosiglitazone, pioglitazone, D‐chiro‐inositol) for women with… (2017) · Cochrane | OR 1.59 [1.27, 1.99] | 16 studies · 1529 participants | Moderate |
Natural cycle FET vs HT FET Live birth rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
Natural cycle FET vs modified natural cycle FET (HCG trigger) Miscarriage rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 0.2 [0.01, 4.13] | 1 study · 168 participants | Very low |
Natural cycle FET vs modified natural cycle FET (HCG trigger) Ongoing pregnancy rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 2.44 [1.03, 5.76] | 1 study · 168 participants | Very low |
Natural cycle FET vs modified natural cycle FET (HCG trigger) Multiple pregnancy per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
Modified natural cycle FET (HCG trigger) vs HT FET Live birth rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 1.34 [0.88, 2.05] | 1 study · 959 participants | Low |
Modified natural cycle FET (HCG trigger) vs HT FET Miscarriage rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
Modified natural cycle FET (HCG trigger) vs HT FET Ongoing pregnancy rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 1.21 [0.8, 1.83] | 1 study · 959 participants | Low |
Modified natural cycle FET (HCG trigger) vs HT FET Multiple pregnancy rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
Modified natural cycle FET (HCG trigger) vs HT + GnRHa suppression FET Live birth rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 1.11 [0.66, 1.87] | 1 study · 236 participants | Low |
Modified natural cycle FET (HCG trigger) vs HT + GnRHa suppression FET Miscarriage rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 0.74 [0.25, 2.19] | 1 study · 236 participants | Low |
Modified natural cycle FET (HCG trigger) vs HT + GnRHa suppression FET Ongoing pregnancy rate · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
Natural cycle FET vs HT FET Miscarriage rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
Modified natural cycle FET (HCG trigger) vs HT + GnRHa suppression FET Multiple pregnancy rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
HT FET vs HT + GnRHa FET Live birth rate per woman · women with primary or secondary subfertility Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 0.1 [0.04, 0.3] | 1 study · 75 participants | Low |
HT FET vs HT + GnRHa FET Miscarriage rate per woman · women with primary or secondary subfertility Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 0.64 [0.37, 1.12] | 6 studies · 991 participants | Low |
HT FET vs HT + GnRHa FET Ongoing pregnancy rate per woman · women with primary or secondary subfertility Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 1.72 [0.61, 4.85] | 1 study · 106 participants | Very low |
HT FET vs HT + GnRHa FET Multiple pregnancy rate per woman · women with primary or secondary subfertility Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
HMG FET vs clomiphene + HMG FET Live birth rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 2.49 [1.07, 5.8] | 1 study · 209 participants | Very low |
HMG FET vs clomiphene + HMG FET Miscarriage rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 1.33 [0.35, 5.09] | 1 study · 209 participants | Very low |
HMG FET vs clomiphene + HMG FET Ongoing pregnancy rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
HMG FET vs clomiphene + HMG FET Multiple pregnancy rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 1.41 [0.31, 6.48] | 1 study · 209 participants | Very low |
Natural cycle FET vs HT FET Ongoing pregnancy rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
Natural cycle FET vs HT FET Multiple pregnancy rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 2.48 [0.09, 68.14] | 1 study · 21 participants | Very low |
Natural cycle FET vs HT plus GnRHa suppression FET Live birth rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 0.77 [0.39, 1.53] | 1 study · 159 participants | Low |
Natural cycle FET vs HT plus GnRHa suppression FET Miscarriage rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
Natural cycle FET vs HT plus GnRHa suppression FET Ongoing pregnancy rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | no estimate extracted | NR | No studies |
Natural cycle FET vs HT plus GnRHa suppression FET Multiple pregnancy rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 0.58 [0.13, 2.5] | 1 study · 159 participants | Low |
Natural cycle FET vs modified natural cycle FET (HCG trigger) Live birth rate per woman · subfertile women Cycle regimens for frozen‐thawed embryo transfer (2017) · Cochrane | OR 0.55 [0.16, 1.93] | 1 study · 60 participants | Very low |