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Search review questions
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 |
|---|---|---|---|
Starting administration of the progestogen earlier vs starting administration of the progestogen later Live birth rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Starting administration of the progestogen earlier vs starting administration of the progestogen later Clinical pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 1.87 [1.13, 3.08] | 1 study · 282 participants | Moderate |
Starting administration of the progestogen earlier vs starting administration of the progestogen later Miscarriage Rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.45 [0.16, 1.25] | 1 study · 191 participants | Very low |
Starting administration of the progestogen earlier vs starting administration of the progestogen later Multiple pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | 1 study · 282 participants | Very low |
Starting administration of the progestogen earlier vs starting administration of the progestogen later Cycle cancellation rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.28 [0.11, 0.74] | 1 study · 282 participants | Moderate |
Starting administration of the progestogen earlier vs starting administration of the progestogen later Endometrial thickness · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Starting administration of the progestogen earlier vs starting administration of the progestogen later Other adverse effects · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
GnRH agonists vs control Live birth rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 2.62 [1.19, 5.78] | 1 study · 234 participants | Low |
Stimulated cycle vs programmed Miscarriage rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.79 [0.36, 1.71] | 3 studies · 355 participants | Very low |
GnRH agonists vs control Clinical pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 1.08 [0.82, 1.43] | 8 studies · 1289 participants | Low |
GnRH agonists vs control Miscarriage rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.85 [0.36, 2] | 4 studies · 828 participants | Low |
GnRH agonists vs control Multiple pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
GnRH agonists vs control Cycle cancellation cycles · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.49 [0.21, 1.17] | 2 studies · 530 participants | Low |
GnRH agonists vs control Endometrial thickness (mm) · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | 4 studies · 697 participants | Low |
GnRH agonists vs control Other adverse effects · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Among different GnRH agonists vs placebo Live birth rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Among different GnRH agonists vs placebo Clinical pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 1.93 [0.62, 5.98] | 1 study · 50 participants | Very low |
Among different GnRH agonists vs placebo Miscarriage rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 1.33 [0.36, 4.87] | 1 study · 68 participants | Very low |
Among different GnRH agonists vs placebo Multiple pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Stimulated cycle vs programmed Multiple pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Among different GnRH agonists vs placebo Cycle cancellation rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Among different GnRH agonists vs placebo Endometrial thickness (mm) · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Among different GnRH agonists vs placebo Other adverse effects · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
GnRH agonists vs GnRH antagonists Live birth rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
GnRH agonists vs GnRH antagonists Clinical pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.62 [0.42, 0.9] | 1 study · 473 participants | Moderate |
GnRH agonists vs GnRH antagonists Miscarriage rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.75 [0.38, 1.49] | 1 study · 473 participants | Low |
GnRH agonists vs GnRH antagonists Multiple pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.69 [0.45, 1.07] | 1 study · 473 participants | Low |
GnRH agonists vs GnRH antagonists Cycle cancellation rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
GnRH agonists vs GnRH antagonists Endometrial thickness (mm) · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
GnRH agonists vs GnRH antagonists Other adverse effects · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Stimulated cycle vs programmed Cycle cancellation rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Aspirin vs control Live birth rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 6 [1.48, 24.3] | 1 study · 60 participants | Very low |
Aspirin vs control Clinical pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 3.33 [1, 11.14] | 1 study · 60 participants | Very low |
Aspirin vs control Miscarriage rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Aspirin vs control Multiple pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Aspirin vs control Cycle cancellation rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Aspirin vs control Endometrial thickness (mm) · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | 1 study · 60 participants | Very low |
Aspirin vs control Other adverse effects · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Steroids vs control Live birth rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.66 [0.14, 3.11] | 1 study · 99 participants | Very low |
Steroids vs control Clinical pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.9 [0.4, 2.03] | 2 studies · 160 participants | Very low |
Steroids vs control Miscarriage rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 1.49 [0.32, 7.03] | 2 studies · 160 participants | Very low |
Stimulated cycle vs programmed Endometrial thickness (mm) · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | 2 studies · 362 participants | Low |
Steroids vs control Multiple pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Steroids vs control Cycle cancellation rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Steroids vs control Endometrial thickness (mm) · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Steroids vs control Other adverse effects · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Stimulated cycle vs programmed Other adverse effects · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | no estimate extracted | NR | No studies |
Natural cycle vs programmed cycle Live birth rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.97 [0.74, 1.28] | 4 studies · 1285 participants | Very low |
Natural cycle vs programmed cycle Clinical pregnancy rate · women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from… (2020) · Cochrane | OR 0.79 [0.62, 1.01] | 5 studies · 1249 participants | Very low |
The LNG‐IUS with endometrial surveillance vs endometrial surveillance alone Endometrial polyps · women with breast cancer on adjuvant tamoxifen Levonorgestrel intrauterine system for endometrial protection in women with breast cancer on adjuvant… (2020) · Cochrane | OR 0.22 [0.13, 0.39] | 4 studies · 417 participants | Moderate |