What do systematic reviews say?

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

Swim‐up technique vs wash and centrifugation

It is very uncertain whether swim‐up 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 0.49 [0.02, 13.28]
  1 study · 26 participants
  Very low

Gonadotropins with GnRH agonists vs gonadotropins alone

It is very uncertain whether gonadotropins with GnRH agonists changes multiple pregnancy rate per couple compared with gonadotropins alone (very low certainty).

• Agents for ovarian stimulation for intrauterine insemination (IUI) in ovulatory women with infertility 2021 · Cochrane Headline outcomes only
  OR 2.53 [0.82, 7.86]
  2 studies · 264 participants
  Very low

Gonadotropins with GnRH antagonist vs gonadotropins alone

Gonadotropins with GnRH antagonist showed no clear difference in multiple pregnancy rate per couple compared with gonadotropins alone (moderate certainty).

• Agents for ovarian stimulation for intrauterine insemination (IUI) in ovulatory women with infertility 2021 · Cochrane Headline outcomes only
  OR 1.3 [0.74, 2.28]
  10 studies · 2095 participants
  Moderate

Gonadotropins vs anti‐oestrogens

Gonadotropins showed no clear difference in multiple pregnancy rate per couple compared with anti‐oestrogens (low certainty).

• Agents for ovarian stimulation for intrauterine insemination (IUI) in ovulatory women with infertility 2021 · Cochrane Headline outcomes only
  OR 1.58 [0.6, 4.17]
  7 studies · 2139 participants
  Low

Gonadotrophins with anti‐oestrogens vs gonadotropins alone

Gonadotrophins with anti‐oestrogens showed no clear difference in multiple pregnancy rate per couple compared with gonadotropins alone (low certainty).

• Agents for ovarian stimulation for intrauterine insemination (IUI) in ovulatory women with infertility 2021 · Cochrane Headline outcomes only
  OR 3.03 [0.12, 75.06]
  1 study · 230 participants
  Low

Aromatase inhibitors vs gonadotropins alone

It is very uncertain whether aromatase inhibitors changes multiple pregnancy rate per couple compared with gonadotropins (very low certainty).

• Agents for ovarian stimulation for intrauterine insemination (IUI) in ovulatory women with infertility 2021 · Cochrane Headline outcomes only
  OR 0.69 [0.06, 8.17]
  3 studies · 731 participants
  Very low

Aromatase inhibitors with gonadotropins vs anti‐oestrogens with gonadotropins

Aromatase inhibitors with gonadotropins showed no clear difference in multiple pregnancy rate per couple compared with anti‐oestrogens with gonadotropins (low certainty).

• Agents for ovarian stimulation for intrauterine insemination (IUI) in ovulatory women with infertility 2021 · Cochrane Headline outcomes only
  OR 1.31 [0.39, 4.37]
  4 studies · 901 participants
  Low

Aromatase inhibitors vs anti‐oestrogens

Aromatase inhibitors showed no clear difference in multiple pregnancy rate per couple compared with anti‐oestrogens (low certainty).

• Agents for ovarian stimulation for intrauterine insemination (IUI) in ovulatory women with infertility 2021 · Cochrane Headline outcomes only
  OR 1.28 [0.61, 2.68]
  4 studies · 1000 participants
  Low

IUI in a stimulated cycle vs TI or expectant management

IUI in a stimulated cycle showed no clear difference in multiple pregnancy rate per couple compared with TI or expectant management (low certainty).

• Intra‐uterine insemination for unexplained subfertility 2020 · Cochrane Headline outcomes only
  OR 3.01 [0.47, 19.28]
  2 studies · 454 participants
  Low
• Intra‐uterine insemination for unexplained subfertility 2020 · Cochrane Headline outcomes only
  OR 1.46 [0.55, 3.87]
  4 studies · 316 participants
  Low

IUI in a natural cycle vs TI or expectant management

IUI in a natural cycle showed no clear difference in multiple pregnancy rate per couple compared with TI or expectant management (low certainty).

• Intra‐uterine insemination for unexplained subfertility 2020 · Cochrane Headline outcomes only
  OR 0.5 [0.04, 5.53]
  1 study · 334 participants
  Low
• Intra‐uterine insemination for unexplained subfertility 2020 · Cochrane Headline outcomes only
  OR 1.05 [0.07, 16.9]
  1 study · 342 participants
  Low

IUI in a stimulated cycle vs IUI

IUI in a stimulated cycle showed no clear difference in multiple pregnancy rate per couple compared with IUI (low certainty).

• Intra‐uterine insemination for unexplained subfertility 2020 · Cochrane Headline outcomes only
  OR 3 [0.11, 78.27]
  1 study · 39 participants
  Low

Ultrasound‐guided transvaginal ovarian needle drilling with gonadotropin (Gn) vs Gn

It is very uncertain whether ultrasound‐guided transvaginal ovarian needle drilling with… changes multiple pregnancy rate (per woman) compared with gn (very low certainty).

• Ultrasound-guided transvaginal ovarian needle drilling for clomiphene-resistant polycystic ovarian syndrome in… 2019 · Cochrane Headline outcomes only
  OR 1.25 [0.27, 5.77]
  2 studies · 155 participants
  Very low

Modified natural cycle FET (HCG trigger) vs HT 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

HT FET 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

HMG FET vs clomiphene + HMG FET

It is very uncertain whether HMG FET changes multiple pregnancy rate per woman compared with clomiphene + HMG FET (very low certainty).

• Cycle regimens for frozen‐thawed embryo transfer 2017 · Cochrane Headline outcomes only
  OR 1.41 [0.31, 6.48]
  1 study · 209 participants
  Very low

Natural cycle FET vs HT FET

It is very uncertain whether natural cycle FET changes multiple pregnancy rate per woman compared with HT FET (very low certainty).

• Cycle regimens for frozen‐thawed embryo transfer 2017 · Cochrane Headline outcomes only
  OR 2.48 [0.09, 68.14]
  1 study · 21 participants
  Very low