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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 |
|---|---|---|---|
Summary of findings table ‐ Progestogens vs GnRH antagonists Live birth or ongoing pregnancy ‐ Poor‐responders (MPA 10 mg versus GnRH antagonists) ‐ Own oocytes ‐ Early phase stimulation protocol · assisted reproduction technology cycles Progestogens for prevention of luteinising hormone (LH) surge in women undergoing controlled ovarian… (2023) · Cochrane | OR 1.25 [0.73, 2.13] | 1 study · 340 participants | Ungraded |
Summary of findings table ‐ Progestogens vs GnRH antagonists Oocyte pick‐up cancellation ‐ Normoresponders (MPA 10 mg versus GnRH antagonists) ‐ Donor oocytes ‐ Early phase stimulation protocol ‐ Fresh embryo transfer · assisted reproduction technology cycles Progestogens for prevention of luteinising hormone (LH) surge in women undergoing controlled ovarian… (2023) · Cochrane | OR 0.84 [0.28, 2.55] | 2 studies · 534 participants | Ungraded |
Summary of findings table ‐ Progestogens vs GnRH antagonists Oocyte pick‐up cancellation ‐ Normoresponders (micronised progesterone 200 mg versus GnRH antagonists) ‐ Own oocytes ‐ Early phase stimulation protocol ‐ Fresh embryo transfer · assisted reproduction technology cycles Progestogens for prevention of luteinising hormone (LH) surge in women undergoing controlled ovarian… (2023) · Cochrane | OR 1 [0.33, 3.06] | 1 study · 114 participants | Ungraded |
Summary of findings table ‐ Progestogens vs GnRH antagonists Cumulative pregnancy rate · assisted reproduction technology cycles Progestogens for prevention of luteinising hormone (LH) surge in women undergoing controlled ovarian… (2023) · Cochrane | no estimate extracted | 1 study · 1 participants | Ungraded |
Summary of findings table ‐ Progestogens vs GnRH antagonists Premature LH surge ‐ Donor oocytes ‐ Normoresponders ‐ Early phase stimulation protocol ‐ Fresh embryo transfer · assisted reproduction technology cycles Progestogens for prevention of luteinising hormone (LH) surge in women undergoing controlled ovarian… (2023) · Cochrane | no estimate extracted | 1 study · 1 participants | Ungraded |
GnRHas vs no treatment No studies included for any outcomes · Women with endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | NR | No studies |
GnRHas vs danazol Relief of overall pain ‐ 6 months · Women with pain due to endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | 1 study · 41 participants | Very low |
GnRHas vs danazol Relief of overall pain ‐ reported as pelvic pain ‐ 6 months · Women with pain due to endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | 1 study · 41 participants | Very low |
GnRHas vs danazol Relief of overall pain ‐ reported as dysmenorrhoea ‐ 6 months · Women with pain due to endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | 1 study · 41 participants | Very low |
GnRHas vs danazol Relief of overall pain ‐ reported as pelvic induration ‐ 6 months · Women with pain due to endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | 1 study · 41 participants | Very low |
GnRHas vs danazol Relief of overall pain ‐ reported as pelvic tenderness ‐ 6 months · Women with pain due to endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | 1 study · 41 participants | Very low |
GnRHas vs intra‐uterine progestogens device No studies included with only low risk of bias · Women with pain due to endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Effect of GnRHas vs other hormonal treatment on bone mineral density GnRHas vs gestrinone Percentage change values ‐ 6 months · Women with endometriosis, treated with GnRHas with effect on bone mineral density Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | 1 study · 41 participants | Very low |
Effect of GnRHas vs other hormonal treatment on bone mineral density GnRHas vs gestrinone Percentage change values ‐ 12 months · Women with endometriosis, treated with GnRHas with effect on bone mineral density Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | 1 study · 41 participants | Very low |
Effect of GnRHas vs other hormonal treatment on bone mineral density GnRHas vs GnRHas in conjunction with calcium‐regulating agents Anterior‐posterior spine ‐ 12 months · Women with endometriosis, treated with GnRHas with effect on bone mineral density Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | 1 study · 43 participants | Very low |
Effect of GnRHas vs other hormonal treatment on bone mineral density GnRHas vs GnRHas in conjunction with calcium‐regulating agents Lateral spine ‐ 12 months · Women with endometriosis, treated with GnRHas with effect on bone mineral density Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | 1 study · 43 participants | Very low |
GnRHas vs placebo Relief of overall pain ‐ reported as pelvic pain ‐ 3 months · Women with endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | RR 2.14 [1.41, 3.24] | 1 study · 87 participants | Low |
GnRHas vs placebo Relief of overall pain ‐ reported as dysmenorrhoea ‐ 3 months · Women with endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | RR 2.25 [1.59, 3.16] | 1 study · 87 participants | Low |
GnRHas vs placebo Relief of overall pain ‐ reported as dyspareunia ‐ 3 months · Women with endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | RR 2.21 [1.39, 3.54] | 1 study · 87 participants | Low |
GnRHas vs placebo Relief of overall pain ‐ reported as pelvic tenderness scores‐ 3 months · Women with endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | RR 2.28 [1.48, 3.5] | 1 study · 87 participants | Low |
GnRHas vs placebo Relief of overall pain ‐ reported as pelvic induration scores ‐ 3 months · Women with endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | RR 1.07 [0.64, 1.79] | 1 study · 87 participants | Low |
GnRHas vs analgesics No studies included for any outcomes · Women with pain due to endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | no estimate extracted | NR | No studies |
GnRHas vs danazol Relief of overall pain ‐ reported as pelvic tenderness, partly resolved ‐ 6 months · Women with pain due to endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | RR 1.15 [0.49, 2.73] | 1 study · 41 participants | Very low |
GnRHas vs danazol Relief of overall pain ‐ reported as pelvic tenderness, complete resolved ‐ 6 months · Women with pain due to endometriosis Gonadotropin‐releasing hormone analogues for endometriosis (2023) · Cochrane | RR 1.1 [0.67, 1.81] | 1 study · 41 participants | Very low |
Blastocyst‐stage vs cleavage‐stage embryo transfer Outcomes per couple · women and couples with subfertility Cleavage‐stage versus blastocyst‐stage embryo transfer in assisted reproductive technology (2022) · Cochrane | no estimate extracted | NR | No studies |
Blastocyst‐stage vs cleavage‐stage embryo transfer Live birth rate per fresh transfer · women and couples with subfertility Cleavage‐stage versus blastocyst‐stage embryo transfer in assisted reproductive technology (2022) · Cochrane | OR 1.27 [1.06, 1.51] | 15 studies · 2219 participants | Low |
Blastocyst‐stage vs cleavage‐stage embryo transfer Cumulative pregnancy rate (slow freezing) · women and couples with subfertility Cleavage‐stage versus blastocyst‐stage embryo transfer in assisted reproductive technology (2022) · Cochrane | OR 0.69 [0.48, 0.99] | 4 studies · 512 participants | Low |
Blastocyst‐stage vs cleavage‐stage embryo transfer Cumulative pregnancy rate (vitrification) · women and couples with subfertility Cleavage‐stage versus blastocyst‐stage embryo transfer in assisted reproductive technology (2022) · Cochrane | OR 2.44 [1.17, 5.12] | 1 study · 120 participants | Moderate |
Blastocyst‐stage vs cleavage‐stage embryo transfer Clinical pregnancy rate · women and couples with subfertility Cleavage‐stage versus blastocyst‐stage embryo transfer in assisted reproductive technology (2022) · Cochrane | OR 1.25 [1.12, 1.39] | 32 studies · 5821 participants | Moderate |
Blastocyst‐stage vs cleavage‐stage embryo transfer Multiple pregnancy rate · women and couples with subfertility Cleavage‐stage versus blastocyst‐stage embryo transfer in assisted reproductive technology (2022) · Cochrane | OR 1.12 [0.9, 1.38] | 22 studies · 4208 participants | Low |
Blastocyst‐stage vs cleavage‐stage embryo transfer Miscarriage rate · women and couples with subfertility Cleavage‐stage versus blastocyst‐stage embryo transfer in assisted reproductive technology (2022) · Cochrane | OR 1.24 [0.98, 1.57] | 21 studies · 4106 participants | Low |
Blastocyst‐stage vs cleavage‐stage embryo transfer Embryo freezing rate · women and couples with subfertility Cleavage‐stage versus blastocyst‐stage embryo transfer in assisted reproductive technology (2022) · Cochrane | OR 0.48 [0.4, 0.57] | 14 studies · 2292 participants | Low |
Blastocyst‐stage vs cleavage‐stage embryo transfer Failure rate to transfer any embryos · women and couples with subfertility Cleavage‐stage versus blastocyst‐stage embryo transfer in assisted reproductive technology (2022) · Cochrane | OR 2.5 [1.76, 3.55] | 17 studies · 2577 participants | Moderate |
Summary of findings table ‐ Aspiration/flush vs aspiration Live birth rate ‐ total · women undergoing assisted conception Follicular flushing during oocyte retrieval in assisted reproductive techniques (2022) · Cochrane | OR 0.93 [0.59, 1.46] | 4 studies · 467 participants | Moderate |
Summary of findings table ‐ Aspiration/flush vs aspiration Miscarriage rate ‐ total · women undergoing assisted conception Follicular flushing during oocyte retrieval in assisted reproductive techniques (2022) · Cochrane | OR 1.98 [0.18, 22.22] | 1 study · 164 participants | Low |
Summary of findings table ‐ Aspiration/flush vs aspiration Oocyte yield per woman randomised (normally distributed data) · women undergoing assisted conception Follicular flushing during oocyte retrieval in assisted reproductive techniques (2022) · Cochrane | no estimate extracted | 9 studies · 1239 participants | Very low |
Summary of findings table ‐ Aspiration/flush vs aspiration Duration of oocyte retrieval (normally distributed data; seconds) · women undergoing assisted conception Follicular flushing during oocyte retrieval in assisted reproductive techniques (2022) · Cochrane | no estimate extracted | 7 studies · 785 participants | Low |
Summary of findings table ‐ Aspiration/flush vs aspiration Total number of embryos (normally distributed data) · women undergoing assisted conception Follicular flushing during oocyte retrieval in assisted reproductive techniques (2022) · Cochrane | no estimate extracted | 2 studies · 160 participants | Low |
Summary of findings table ‐ Aspiration/flush vs aspiration Clinical pregnancy rate per woman randomised · women undergoing assisted conception Follicular flushing during oocyte retrieval in assisted reproductive techniques (2022) · Cochrane | OR 1.13 [0.85, 1.51] | 7 studies · 939 participants | Low |
Summary of findings table ‐ Aspiration/flush vs aspiration Adverse events (dichotomous data) ‐ total · women undergoing assisted conception Follicular flushing during oocyte retrieval in assisted reproductive techniques (2022) · Cochrane | no estimate extracted | 3 studies · 3 participants | Low |
Glucocorticoids vs no glucocorticoids or placebo Live birth rate per couple · women receiving assisted reproductive technology cycles Peri‐implantation glucocorticoid administration for assisted reproductive technology cycles (2022) · Cochrane | OR 1.37 [0.69, 2.71] | 2 studies · 366 participants | Very low |
Glucocorticoids vs no glucocorticoids or placebo Miscarriage rate per couple · women receiving assisted reproductive technology cycles Peri‐implantation glucocorticoid administration for assisted reproductive technology cycles (2022) · Cochrane | OR 1.09 [0.63, 1.87] | 6 studies · 821 participants | Very low |
Glucocorticoids vs no glucocorticoids or placebo Incidence of ectopic pregnancies per couple · women receiving assisted reproductive technology cycles Peri‐implantation glucocorticoid administration for assisted reproductive technology cycles (2022) · Cochrane | OR 2.28 [0.33, 15.62] | 3 studies · 320 participants | Very low |
Glucocorticoids vs no glucocorticoids or placebo Incidence of OHSS per couple (mild–severe) · women receiving assisted reproductive technology cycles Peri‐implantation glucocorticoid administration for assisted reproductive technology cycles (2022) · Cochrane | OR 1.07 [0.6, 1.9] | 3 studies · 370 participants | Very low |
Glucocorticoids vs no glucocorticoids or placebo Incidence of multiple pregnancies per couple · women receiving assisted reproductive technology cycles Peri‐implantation glucocorticoid administration for assisted reproductive technology cycles (2022) · Cochrane | OR 0.86 [0.33, 2.2] | 4 studies · 504 participants | Very low |
Glucocorticoids vs no glucocorticoids or placebo Ongoing pregnancy rate per couple · women receiving assisted reproductive technology cycles Peri‐implantation glucocorticoid administration for assisted reproductive technology cycles (2022) · Cochrane | OR 1.19 [0.8, 1.76] | 3 studies · 476 participants | Very low |
Glucocorticoids vs no glucocorticoids or placebo Clinical pregnancy rate per couple –pregnancy rate per couple (primary analysis) · women receiving assisted reproductive technology cycles Peri‐implantation glucocorticoid administration for assisted reproductive technology cycles (2022) · Cochrane | OR 1.17 [0.95, 1.44] | 13 studies · 1967 participants | Low |
Glucocorticoids vs no glucocorticoids or placebo Clinical pregnancy rate per couple – subgroup IVF · women receiving assisted reproductive technology cycles Peri‐implantation glucocorticoid administration for assisted reproductive technology cycles (2022) · Cochrane | OR 1.44 [1, 2.08] | 5 studies · 724 participants | Very low |
Glucocorticoids vs no glucocorticoids or placebo Clinical pregnancy rate per couple – subgroup ICSI · women receiving assisted reproductive technology cycles Peri‐implantation glucocorticoid administration for assisted reproductive technology cycles (2022) · Cochrane | OR 1.08 [0.81, 1.42] | 6 studies · 992 participants | Very low |
Glucocorticoids vs no glucocorticoids or placebo Clinical pregnancy rate per couple: dosage and timing of glucocorticoids – clinical pregnancy rate: lower dose glucocorticoids · women receiving assisted reproductive technology cycles Peri‐implantation glucocorticoid administration for assisted reproductive technology cycles (2022) · Cochrane | OR 1.2 [0.87, 1.67] | 6 studies · 780 participants | Very low |