Gap finder
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 |
|---|---|---|---|
Clomiphene citrate or letrozole with or without gonadotropins (with or without midcycle antagonist) vs gonadotropins (with GnRH agonist or midcycle antagonist) Mean number of gonadotropin ampoules used per woman · Women undergoing controlled ovarian stimulation in IVF and ICSI cycles (poor responders) Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled… (2017) · Cochrane | no estimate extracted | 3 studies · 136 participants | Moderate |
Clomiphene citrate or letrozole with or without gonadotropins (with or without midcycle antagonist) vs gonadotropins (with GnRH agonist or midcycle antagonist) Mean number of oocytes retrieved per woman · Women undergoing controlled ovarian stimulation in IVF and ICSI cycles (poor responders) Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled… (2017) · Cochrane | no estimate extracted | 8 studies · 1203 participants | Moderate |
Clomiphene citrate or letrozole with or without gonadotropins (with or without midcycle antagonist) vs gonadotropins (with GnRH agonists or midcycle antagonist) Ovarian hyperstimulation syndrome per woman · for controlled ovarian stimulation Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled… (2017) · Cochrane | Peto OR 0.21 [0.11, 0.41] | 5 studies · 1067 participants | Low |
Clomiphene citrate or letrozole with or without gonadotropins (with or without midcycle antagonist) vs gonadotropins (with GnRH agonists or midcycle antagonist) Clinical pregnancy rate per woman · for controlled ovarian stimulation Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled… (2017) · Cochrane | RR 1 [0.86, 1.16] | 12 studies · 1998 participants | Moderate |
Clomiphene citrate or letrozole with or without gonadotropins (with or without midcycle antagonist) vs gonadotropins (with GnRH agonists or midcycle antagonist) Cancellation rate per woman · for controlled ovarian stimulation Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled… (2017) · Cochrane | RR 1.87 [1.43, 2.45] | 9 studies · 1784 participants | Low |
Clomiphene citrate or letrozole with or without gonadotropins (with or without midcycle antagonist) vs gonadotropins (with GnRH agonists or midcycle antagonist) Mean number of gonadotropin ampoules used per woman · for controlled ovarian stimulation Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled… (2017) · Cochrane | no estimate extracted | 6 studies · 1098 participants | Moderate |
Clomiphene citrate or letrozole with or without gonadotropins (with or without midcycle antagonist) vs gonadotropins (with GnRH agonists or midcycle antagonist) Mean number of oocytes retrieved per woman · for controlled ovarian stimulation Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled… (2017) · Cochrane | no estimate extracted | 8 studies · 1481 participants | Moderate |
Clomiphene citrate or letrozole with or without gonadotropins (with or without midcycle antagonist) vs gonadotropins (with GnRH agonist or midcycle antagonist) Live birth per woman · Women undergoing controlled ovarian stimulation in IVF and ICSI cycles (poor responders) Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled… (2017) · Cochrane | RR 1.16 [0.49, 2.79] | 2 studies · 357 participants | Low |
Clomiphene citrate or letrozole with or without gonadotropins (with or without midcycle antagonist) vs gonadotropins (with GnRH agonist or midcycle antagonist) Clinical pregnancy rate per woman · Women undergoing controlled ovarian stimulation in IVF and ICSI cycles (poor responders) Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled… (2017) · Cochrane | RR 0.85 [0.64, 1.12] | 8 studies · 1462 participants | Low |
Clomiphene citrate or letrozole with or without gonadotropins (with or without midcycle antagonist) vs gonadotropins (with GnRH agonist or midcycle antagonist) Cancellation rate per woman · Women undergoing controlled ovarian stimulation in IVF and ICSI cycles (poor responders) Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled… (2017) · Cochrane | RR 1.46 [1.18, 1.81] | 10 studies · 1601 participants | Low |
Metformin vs placebo co‐treatment Live birth rate (per woman) · patients with subfertility associated with polycystic ovary syndrome Metformin during ovulation induction with gonadotrophins followed by timed intercourse or intrauterine… (2017) · Cochrane | OR 2.31 [1.24, 4.33] | 2 studies · 180 participants | Low |
Metformin vs placebo co‐treatment Multiple pregnancy rate (per woman) · patients with subfertility associated with polycystic ovary syndrome Metformin during ovulation induction with gonadotrophins followed by timed intercourse or intrauterine… (2017) · Cochrane | OR 0.55 [0.15, 1.95] | 4 studies · 232 participants | Low |
Metformin vs placebo co‐treatment Ongoing pregnancy rate (per woman) · patients with subfertility associated with polycystic ovary syndrome Metformin during ovulation induction with gonadotrophins followed by timed intercourse or intrauterine… (2017) · Cochrane | OR 2.46 [1.36, 4.46] | 4 studies · 232 participants | Low |
Metformin vs placebo co‐treatment Clinical pregnancy rate (per woman) · patients with subfertility associated with polycystic ovary syndrome Metformin during ovulation induction with gonadotrophins followed by timed intercourse or intrauterine… (2017) · Cochrane | OR 2.51 [1.46, 4.31] | 5 studies · 264 participants | Low |
LOD vs medical interventions Menstrual regularity at 6 months LOD vs metformin N of participants: 236 (2 RCTs) LOD vs metformin + clomiphene N of participants: 332 (2 RCTs) LOD vs gonadotropins N of participants: 35 (1 RCT) LOD vs letrozole N of participants: 260 (1 RCT) LOD ... · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | no estimate extracted | NR | Very low |
LOD vs other surgical interventions Harms: Adhesions at 6 months ‐ LOD vs THL N of participants: 246 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 0.1 [0.05, 0.18] | NR | Very low |
LOD 4‐5 vs 2 or fewer punctures Menstrual regularity at 6 months ‐ LOD 4 ‐ 5 coagulation points compared to 2 or fewer N of participants: 73 (2 RCTs) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 16.04 [4.19, 61.34] | NR | Low |
LOD 4‐5 vs 2 or fewer punctures Menstrual regularity at 6 months ‐ LOD (4 ‐ 5 laser coagulation points) vs 1 laser coagulation point per ovary N of participants: 40 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 19 [2.12, 170.38] | NR | Low |
LOD 4‐5 vs 2 or fewer punctures Menstrual regularity at 6 months ‐ LOD 4 punctures vs 2 punctures per ovary N of participants: 33 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 14 [2.6, 75.41] | NR | Low |
LOD 4‐5 vs 2 or fewer punctures Improvement in androgenic symptoms · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | no estimate extracted | NR | No studies |
LOD 4‐5 vs 2 or fewer punctures Harms LOD 4 ‐ 5 versus fewer punctures · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | no estimate extracted | NR | No studies |
LOD vs LOD variable energy Menstrual regularity at 6 months ‐ LOD vs adjusted thermal dose N of participants: 115 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 0.42 [0.16, 1.14] | NR | Very low |
LOD vs LOD variable energy Menstrual regularity at 3 months ‐ LOD unipolar vs LOD bipolar N of participants: 20 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 1 [0.05, 18.57] | NR | Very low |
LOD vs LOD variable energy Improvement in androgenic symptoms · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | no estimate extracted | NR | No studies |
LOD vs LOD variable energy Harms: Adhesions at 6 months № of participants: 64 (1 study) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 0.96 [0.32, 2.88] | NR | Very low |
LOD vs medical interventions Improvement in androgenic symptoms at 6 months (hirsutism/acne) ‐ LOD vs metformin N of participants: 126 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 1 [0.42, 2.37] | NR | Low |
LOD vs medical interventions Improvement in androgenic symptoms at 6 months (hirsutism/acne) ‐ LOD vs gonadotrophins N of participants: 50 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 3.2 [0.33, 30.94] | NR | Very low |
LOD vs medical interventions Harms: GI Upset at 6 months ‐ LOD vs metformin + clomiphene N of participants: 332 (2 RCTs) Harms: OHSS rates at 6 months ‐ LOD vs gonadotrophins N of participants: 33 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 0.05 [0.01, 0.36] | NR | Moderate |
LOD vs other surgical interventions Menstrual regularity ‐ LOD vs unilateral LOD N of participants: 104 (2 RCTs) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 1.51 [0.62, 3.71] | NR | Moderate |
LOD vs other surgical interventions Menstrual regularity at 6 months ‐ LOD vs ultrasound‐guided transvaginal ovarian drilling N of participants: 147 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 1.23 [0.64, 2.37] | NR | Low |
LOD vs other surgical interventions Menstrual regularity at 12 months Laser LOD vs harmonic scalpel N of participants: 34 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 2.13 [0.17, 26.03] | NR | Low |
LOD vs other surgical interventions Improvement in androgenic symptoms at 6 months (Acne) ‐ LOD vs USS guided N of participants:31 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 0.84 [0.2, 3.5] | NR | Low |
LOD vs other surgical interventions Improvement in androgenic symptoms at 6 months (Hirsutism) ‐ LOD vs USS‐guided N of participants: 39 (1 RCT) · Women with symptoms of PCOS Ovarian surgery for symptom relief in women with polycystic ovary syndrome (2017) · Cochrane | OR 1.09 [0.3, 3.91] | NR | Low |
Mifepristone vs placebo Prevalence of dysmenorrhoea · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 0.08 [0.04, 0.17] | 1 study · 352 participants | Moderate |
Gestrinone vs danazol Side effects: hot flushes · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 0.79 [0.5, 1.26] | 2 studies · 302 participants | Very low |
Gestrinone vs danazol Side effects: acne · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 1.45 [0.9, 2.33] | 2 studies · 302 participants | Low |
Gestrinone vs leuprolin Dysmenorrhoea, verbal rating scale · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | no estimate extracted | 1 study · 55 participants | Low |
Gestrinone vs leuprolin Dyspareunia, verbal rating scale · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | no estimate extracted | 1 study · 52 participants | Low |
Gestrinone vs leuprolin Amenorrhoea · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 0.04 [0.01, 0.38] | 1 study · 49 participants | Low |
Gestrinone vs leuprolin Spotting or bleeding · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 22.92 [2.64, 198.66] | 1 study · 49 participants | Low |
Gestrinone vs leuprolin Side effects: hot flushes · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 0.2 [0.06, 0.63] | 1 study · 55 participants | Low |
Mifepristone vs placebo Prevalence of dyspareunia · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 0.23 [0.1, 0.51] | 1 study · 223 participants | Low |
Mifepristone vs placebo Side effects: amenorrhoea · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 686.16 [92.29, 5101.33] | 1 study · 360 participants | High |
Mifepristone vs placebo Side effects: hot flushes · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 28.79 [3.93, 210.73] | 1 study · 360 participants | High |
Gestrinone vs danazol Pelvic pain: none or mild · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 0.71 [0.33, 1.56] | 2 studies · 230 participants | Very low |
Gestrinone vs danazol Dysmenorrhoea: none or mild · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 0.72 [0.39, 1.33] | 2 studies · 214 participants | Very low |
Gestrinone vs danazol Dyspareunia: none or mild · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 0.83 [0.37, 1.86] | 2 studies · 222 participants | Very low |
Gestrinone vs danazol Side effects: hirsutism · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 2.63 [1.6, 4.32] | 2 studies · 302 participants | Very low |
Gestrinone vs danazol Decreased breast size · women with symptomatic endometriosis Progesterone receptor modulators for endometriosis (2017) · Cochrane | OR 0.62 [0.38, 0.98] | 2 studies · 302 participants | Low |
Oestrogen in combination with progestogen (sequential or continuous) vs placebo Symptom scores over 2 to 4 menstrual cycles1 · women diagnosed with symptoms of premenstrual syndrome (PMS) Non‐contraceptive oestrogen‐containing preparations for controlling symptoms of premenstrual syndrome (2017) · Cochrane | no estimate extracted | 3 studies · 158 participants | Very low |