What do systematic reviews say?

Summary of findings table ‐ Progestogens vs placebo or no pretreatment

The review found no eligible studies for this question.

• Oral contraceptive pill, progestogen or oestrogen pretreatment for ovarian stimulation protocols for women undergoing… 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found
• Oral contraceptive pill, progestogen or oestrogen pretreatment for ovarian stimulation protocols for women undergoing… 2017 · Cochrane Headline outcomes only
  OR 1.05 [0.06, 17.76]
  1 study · 47 participants
  Low

Combined oral contraceptive pill vs no pretreatment

Combined oral contraceptive pill showed no clear difference in multiple pregnancy rate (COCP + Ant vs Ant) compared with no pretreatment (low certainty).

• Oral contraceptive pill, progestogen or oestrogen pretreatment for ovarian stimulation protocols for women undergoing… 2017 · Cochrane Headline outcomes only
  OR 2.21 [0.53, 9.26]
  2 studies · 125 participants
  Low
• Oral contraceptive pill, progestogen or oestrogen pretreatment for ovarian stimulation protocols for women undergoing… 2017 · Cochrane Headline outcomes only
  OR 1.36 [0.85, 2.19]
  4 studies · 546 participants
  Moderate

Oestrogen vs no pretreatment

The review found no eligible studies for this question.

• Oral contraceptive pill, progestogen or oestrogen pretreatment for ovarian stimulation protocols for women undergoing… 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found
• Oral contraceptive pill, progestogen or oestrogen pretreatment for ovarian stimulation protocols for women undergoing… 2017 · Cochrane Headline outcomes only
  OR 2.24 [0.09, 53.59]
  1 study · 22 participants
  Very low

Embryo culture with low oxygen concentration vs embryo culture with atmospheric oxygen concentration

Embryo culture with low oxygen concentration showed no clear difference in multiple‐pregnancy rate compared with embryo culture with atmospheric oxygen concentration (low certainty).

• Low oxygen concentrations for embryo culture in assisted reproductive technologies 2012 · Cochrane Headline outcomes only
  OR 1.33 [0.91, 1.95]
  4 studies · 1382 participants
  Low

Dopamine agonist plus co‐intervention vs co‐intervention

It is very uncertain whether dopamine agonist plus co‐intervention changes multiple pregnancy rate compared with co‐intervention (very low certainty).

• Dopamine agonists for preventing ovarian hyperstimulation syndrome 2021 · Cochrane Headline outcomes only
  OR 2.02 [0.18, 22.77]
  1 study · 166 participants
  Very low

Dopamine agonist vs other active intervention

Dopamine agonist showed no clear difference in multiple pregnancy rate compared with other active intervention (low certainty).

• Dopamine agonists for preventing ovarian hyperstimulation syndrome 2021 · Cochrane Headline outcomes only
  OR 0.87 [0.47, 1.59]
  3 studies · 400 participants
  Low

Dopamine agonist vs placebo or no intervention

It is very uncertain whether dopamine agonist changes multiple pregnancy rate compared with placebo/no intervention (very low certainty).

• Dopamine agonists for preventing ovarian hyperstimulation syndrome 2021 · Cochrane Headline outcomes only
  OR 0.32 [0.01, 8.26]
  1 study · 40 participants
  Very low

Natural cycle vs programmed cycle

The review found no eligible studies for this question.

• Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Transdermal oestrogens vs oral oestrogens

The review found no eligible studies for this question.

• Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Starting administration of the progestogen earlier vs starting administration of the progestogen later

• Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes 2020 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 282 participants
  Very low

GnRH agonists vs control

The review found no eligible studies for this question.

• Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

GnRH agonists vs placebo

The review found no eligible studies for this question.

• Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Stimulated cycle vs programmed

The review found no eligible studies for this question.

• Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

GnRH agonists vs GnRH antagonists

GnRH agonists showed no clear difference in multiple pregnancy rate compared with gnRH antagonists (low certainty).

• Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes 2020 · Cochrane Headline outcomes only
  OR 0.69 [0.45, 1.07]
  1 study · 473 participants
  Low

Aspirin vs control

The review found no eligible studies for this question.

• Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Steroids vs control

The review found no eligible studies for this question.

• Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Modified natural cycle FET (HCG trigger) vs HT + GnRHa FET

The review found no eligible studies for this question.

• Cycle regimens for frozen‐thawed embryo transfer 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Natural cycle FET vs HT + GnRHa FET

Natural cycle FET showed no clear difference in multiple pregnancy rate per woman compared with HT plus GnRHa suppression FET (low certainty).

• Cycle regimens for frozen‐thawed embryo transfer 2017 · Cochrane Headline outcomes only
  OR 0.58 [0.13, 2.5]
  1 study · 159 participants
  Low

Gradient technique vs wash and centrifugation

It is very uncertain whether gradient technique changes multiple pregnancy rate per couple compared with wash and centrifugation (very low certainty).

• Semen preparation techniques for intrauterine insemination 2019 · Cochrane Headline outcomes only
  OR 0.33 [0.01, 8.83]
  1 study · 31 participants
  Very low

Swim‐up technique vs gradient technique

• Semen preparation techniques for intrauterine insemination 2019 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 25 participants
  Very low