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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 |
|---|---|---|---|
Oral contraceptive pill (OCP) vs metformin combined with OCP Improved menstrual pattern · aAdult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Oral contraceptive pill (OCP) vs metformin combined with OCP Acne ‐ Clinical acne score · aAdult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | 1 study · 82 participants | Low |
Oral contraceptive pill (OCP) vs metformin combined with OCP BMI (kg/m2) · aAdult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | 13 studies · 661 participants | Very low |
Metformin vs oral contraceptive pill (OCP) Hirsutism ‐ Clinical F‐G score · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | 1 study · 16 participants | Very low |
Metformin vs oral contraceptive pill (OCP) Adverse events ‐ Severe · adult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | OR 6.42 [2.98, 13.84] | 11 studies · 602 participants | Low |
Metformin vs oral contraceptive pill (OCP) Adverse event ‐ Severe · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs oral contraceptive pill (OCP) Adverse event ‐ Minor · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | OR 11.67 [0.53, 258.56] | 1 study · 22 participants | Very low |
Metformin vs oral contraceptive pill (OCP) Improved menstrual pattern · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs oral contraceptive pill (OCP) Acne ‐ Visual analogue scale or Clinical acne score · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs oral contraceptive pill (OCP) BMI (kg/m2) · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | 3 studies · 69 participants | Very low |
Metformin vs metformin combined with oral contraceptive pill (OCP) Hirsutism ‐ Clinical F‐G score · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs metformin combined with oral contraceptive pill (OCP) Adverse event ‐ Severe · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs metformin combined with oral contraceptive pill (OCP) Adverse event ‐ Minor · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs metformin combined with oral contraceptive pill (OCP) Improved menstrual pattern · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs metformin combined with oral contraceptive pill (OCP) Acne ‐ Visual analogue scale or Clinical acne score · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs oral contraceptive pill (OCP) Adverse events ‐ Minor · adult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs metformin combined with oral contraceptive pill (OCP) BMI (kg/m2) · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Oral contraceptive pill (OCP) vs metformin combined with OCP Hirsutism ‐ Clinical F‐G score · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | 1 study · 32 participants | Very low |
Oral contraceptive pill (OCP) vs metformin combined with OCP Adverse events ‐ Severe · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | OR 1 [0.06, 17.33] | 1 study · 36 participants | Very low |
Oral contraceptive pill (OCP) vs metformin combined with OCP Adverse events ‐ Minor · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Oral contraceptive pill (OCP) vs metformin combined with OCP Improved menstrual pattern · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Oral contraceptive pill (OCP) vs metformin combined with OCP Acne ‐ Visual analogue scale or Clinical acne score · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Oral contraceptive pill (OCP) vs metformin combined with OCP BMI (kg/m2) · adolescent women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | 1 study · 32 participants | Very low |
Metformin vs oral contraceptive pill (OCP) Improved menstrual pattern · adult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | 2 studies · 153 participants | Low |
Metformin vs oral contraceptive pill (OCP) Acne ‐ Visual analogue scale · adult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | 1 study · 34 participants | Low |
Metformin vs oral contraceptive pill (OCP) BMI (kg/m2) · adult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | 9 studies · 451 participants | Very low |
Metformin vs metformin combined with oral contraceptive pill (OCP) Hirsutism ‐ Clinical F‐G score · adult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | 3 studies · 135 participants | Low |
Metformin vs metformin combined with oral contraceptive pill (OCP) Adverse events ‐ Severe · adult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | OR 0.74 [0.21, 2.53] | 3 studies · 171 participants | Low |
Metformin vs metformin combined with oral contraceptive pill (OCP) Adverse events ‐ Minor · adult women with PCOS Metformin versus the combined oral contraceptive pill for hirsutism, acne, and menstrual pattern in… (2020) · Cochrane | no estimate extracted | NR | No studies |
Metformin vs placebo or no treatment Live birth rate per woman ‐ long protocol GnRH‐agonist · women with polycystic ovary syndrome Metformin treatment before and during IVF or ICSI in women with polycystic ovary syndrome (2020) · Cochrane | RR 1.3 [0.94, 1.79] | 6 studies · 651 participants | Low |
Metformin vs placebo or no treatment Live birth rate per woman ‐ short protocol GnRH‐antagonist · women with polycystic ovary syndrome Metformin treatment before and during IVF or ICSI in women with polycystic ovary syndrome (2020) · Cochrane | RR 0.48 [0.29, 0.79] | 1 study · 153 participants | Low |
Metformin vs placebo or no treatment Incidence of OHSS per woman · women with polycystic ovary syndrome Metformin treatment before and during IVF or ICSI in women with polycystic ovary syndrome (2020) · Cochrane | RR 0.46 [0.29, 0.72] | 11 studies · 1091 participants | Low |
Metformin vs placebo or no treatment Clinical pregnancy rate per woman ‐ long protocol GnRH‐agonist · women with polycystic ovary syndrome Metformin treatment before and during IVF or ICSI in women with polycystic ovary syndrome (2020) · Cochrane | RR 1.32 [1.08, 1.63] | 10 studies · 915 participants | Low |
Metformin vs placebo or no treatment Clinical pregnancy rate per woman ‐ short protocol GnRH‐antagonist · women with polycystic ovary syndrome Metformin treatment before and during IVF or ICSI in women with polycystic ovary syndrome (2020) · Cochrane | RR 1.38 [0.21, 9.14] | 2 studies · 177 participants | Very low |
Metformin vs placebo or no treatment Miscarriage rate per woman · women with polycystic ovary syndrome Metformin treatment before and during IVF or ICSI in women with polycystic ovary syndrome (2020) · Cochrane | RR 0.86 [0.56, 1.32] | 8 studies · 821 participants | Low |
Metformin vs placebo or no treatment Side effects per woman · women with polycystic ovary syndrome Metformin treatment before and during IVF or ICSI in women with polycystic ovary syndrome (2020) · Cochrane | RR 3.35 [2.34, 4.79] | 8 studies · 748 participants | Low |
Stimulated cycle vs programmed 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 1.26 [0.49, 3.26] | 1 study · 100 participants | Very low |
Natural cycle vs programmed cycle 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 0.64 [0.25, 1.63] | 3 studies · 485 participants | Very low |
Natural cycle vs programmed cycle 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 |
Natural cycle vs programmed cycle 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 0.6 [0.44, 0.82] | 1 study · 734 participants | Moderate |
Natural cycle vs programmed cycle 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 | 3 studies · 485 participants | Low |
Natural cycle vs programmed cycle 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 |
Transdermal oestrogens vs oral oestrogens 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 |
Transdermal oestrogens vs oral oestrogens 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 0.86 [0.59, 1.25] | 3 studies · 504 participants | Low |
Transdermal oestrogens vs oral oestrogens 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 0.55 [0.27, 1.09] | 2 studies · 414 participants | Low |
Transdermal oestrogens vs oral oestrogens 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 |
Transdermal oestrogens vs oral oestrogens 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 |
Stimulated cycle vs programmed 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 1.63 [1.12, 2.38] | 5 studies · 656 participants | Low |
Transdermal oestrogens vs oral oestrogens 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 |
Transdermal oestrogens vs oral oestrogens 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 |