Fecundación asistida en la reproducción asistida (fecundación in vitro [FIV] e inyección intracitoplasmática de espermatozoides [ICSI])
Información
- DOI:
- https://doi.org/10.1002/14651858.CD001894.pub6Copiar DOI
- Base de datos:
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- Cochrane Database of Systematic Reviews
- Versión publicada:
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- 17 marzo 2021see what's new
- Tipo:
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- Intervention
- Etapa:
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- Review
- Grupo Editorial Cochrane:
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Grupo Cochrane de Ginecología y fertilidad
- Copyright:
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- Copyright © 2021 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
Cifras del artículo
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Citado por:
Autores
Contributions of authors
Mourad Seif contributed to conceiving the review, designing the review, publishing the protocol, co‐ordinating the review, collecting data for the review, developing a search strategy, undertaking searches, screening search results, organising retrieval of papers, screening retrieved papers against inclusion criteria, arbitrating on quality and data extraction, interpreting data, providing a methodological perspective, providing a clinical perspective, providing a policy perspective, editing the review, providing general advice on the review, and performing previous work that was the foundation of the review.
Muhammad A Akhtar updated this review by extracting data, conducting analysis, and editing the review in detail.
Lauren Lacey updated this review by completing new searches, retrieving papers, screening retrieved papers against inclusion criteria, extracting data, conducting analysis, and editing the review in detail.
Sibte Hassan updated this review by completing new searches, retrieving papers, and screening retrieved papers against inclusion criteria.
Sebastian Franik updated this review by providing support in analysis and editing the review.
Sources of support
Internal sources
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Central Manchester and Manchester Children's University Trust, UK
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University of Manchester, UK
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University of Auckland, New Zealand
External sources
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Ministry of Health, New Zealand
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Dr. Demián Glujovsky, Editor, Cochrane, Other
Translated González‐Ortega et al., 2015 (published in Spanish) and extracted data from the paper for the purposes of this review.
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Dr. Jasmine Lee, Other
Translated Lu et al., 2016 (published in Chinese) and extracted data for the purposes of this review.
Declarations of interest
MAA, SF, SH and LL have no interests to declare. MS has received travel and accommodation support for conferences unrelated to the topic of this review.
Acknowledgements
We wish to thank Helen Nagels and Marian Showell of the Cochrane Gynaecology and Fertility Group for help with literature searches and professional support that was invaluable to this update.
The authors of the 2020 update thank Dr. Debbie Blake and Dr. Kenneth Ma for contributions to early drafts of this update. They also thank Dr Paraskevi Vogiatzi, Dr Annika Strandell and Professor Andy Vail for providing referee comment on the updated review.
We wish to thank Dr. Demián Glujovsky for translating González‐Ortega et al., 2015 (published in Spanish) and for extracting data from the paper for the purposes of this review.
We wish to thank Dr. Jasmine Lee for translating Lu et al., 2016 (published in Chinese) and for extracting data for the purposes of this review.
We wish to thank Dr. Claudia González Ortega and Dr. Iman Halvaei for their correspondence to support the risk of bias assessments for their studies, González‐Ortega 2015 and Razi 2013, respectively.
We acknowledge the editorial board of the Cochrane Gynaecology and Fertility Group for support and advice provided.
We acknowledge the significant contributions of others to the original review and the updates that followed, including previous review authors, S Dias and Prof C Farquhar.
Edmond Edi‐Osagie contributed to the designing and worked on the original review.
Lee Hooper developed the second search strategy, undertook the February 2002 searches, and screened these search results, the late Phil McGinlay contributed to designing the original review, and we acknowledge the contributions of Sarah‐Kate Carney and Linsey Nelson.
Version history
| Published | Title | Stage | Authors | Version |
| 2021 Mar 17 | Assisted hatching on assisted conception (in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI)) | Review | Lauren Lacey, Sibte Hassan, Sebastian Franik, Mourad W Seif, M Ahsan Akhtar | |
| 2012 Dec 12 | Assisted hatching on assisted conception (in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI)) | Review | Sarah‐Kate Carney, Sangeeta Das, Debbie Blake, Cindy Farquhar, Mourad M Seif, Linsey Nelson | |
| 2009 Apr 15 | Assisted hatching on assisted conception (IVF and ICSI) | Review | Sangeeta Das, Debbie Blake, Cindy Farquhar, Mourad MW Seif | |
| 2006 Jan 25 | Assisted hatching on assisted conception (IVF and ICSI) | Review | Sangeeta Das, Debbie Blake, Cindy Farquhar, Mourad MW Seif | |
| 2005 Oct 19 | Assisted hatching on assisted conception (IVF & ICSI) | Review | Mourad MW Seif, Edmond CO Edi‐Osagie, Cindy M Farquhar, Lee Hooper, Debbie A Blake, Phil McGinlay | |
| 2003 Oct 20 | Effect(s) of assisted hatching on assisted conception (IVF & ICSI) | Review | Edmond CO Edi‐Osagie, Lee Hooper, Phil McGinlay, Mourad MW Seif | |
Differences between protocol and review
For the 2005 update, we investigated the following subgroups.
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Age (when reported in the studies) ≥ 35 years.
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First cycle versus previous failed cycles of IVF, ICSI, or both.
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ICSI only cycles.
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Chemical versus laser versus mechanical.
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Thinning versus breach with hole versus complete removal.
For the 2007 update, the subgroup of poor prognosis women (age ≥ 35, poor ovulation induction, previous failed cycles, or referred to as poor prognosis women in the protocol) and new subgroups of fresh and frozen embryo transfer cycles were added.
No new subgroups were added to the 2020 update.
For the 2020 update, the review was reformatted in line with current recommended Cochrane guidance for reporting outcomes.
For the 2020 update, we added exclusion criterion: biopsied embryos were excluded (for purposes of PGS/PGD) during assisted reproduction because essentially they have largely been affected by assisted hatched with a hole made in them routinely at Day 3.
For the 2020 update, we specified which specific outcomes would be subject to sensitivity analysis. Sensitivity analysis was conducted for our primary outcomes and for clinical pregnancy, as those are the most important clinical outcomes.
Keywords
MeSH
Medical Subject Headings (MeSH) Keywords
- Abortion, Spontaneous [epidemiology];
- Bias;
- Embryo Implantation [*physiology];
- *Fertilization in Vitro;
- Live Birth [epidemiology];
- Pregnancy Outcome;
- *Pregnancy Rate;
- Pregnancy, Multiple [statistics & numerical data];
- Publication Bias;
- Randomized Controlled Trials as Topic;
- Sperm Injections, Intracytoplasmic;
- Zona Pellucida [*physiology];
Medical Subject Headings Check Words
Female; Humans; Pregnancy;
PICO
Study flow diagram.
Methodological quality graph: review authors' judgements about each methodological quality item presented as percentages across all included studies.
Methodological quality summary: review authors' judgements about each methodological quality item for each included study.
Forest plot of comparison: 1 Live birth rate, outcome: 1.1 Live birth per woman randomised.
Funnel plot of comparison: 1 Live birth: assisted hatching compared with no assisted hatching, outcome: 1.1 Live birth per woman randomised.
Forest plot of comparison: 4 Multiple pregnancy rate, outcome: 4.1 Multiple pregnancy rate per woman randomised.
Forest plot of comparison: 2 Clinical pregnancy, outcome: 2.1 Clinical pregnancy rate per woman randomised.
Funnel plot of comparison: 3 Clinical pregnancy: assisted hatching compared with no assisted hatching, outcome: 3.1 Clinical pregnancy rate per woman randomised.
Funnel plot of comparison: 4 Clinical pregnancies in trials that reported live births: assisted hatching compared with no assisted hatching, outcome: 4.1 Clinical pregnancies in trials reporting live births.
Forest plot of comparison: 3 Miscarriage rate, outcome: 3.1 Miscarriage per woman randomised.
Forest plot of comparison: 5 Monozygotic twinning rate, outcome: 5.1 Monozygotic twinning per woman randomised.
Comparison 1: Live birth: assisted hatching compared with no assisted hatching, Outcome 1: Live birth per woman randomised
Comparison 1: Live birth: assisted hatching compared with no assisted hatching, Outcome 2: First or repeat attempt
Comparison 1: Live birth: assisted hatching compared with no assisted hatching, Outcome 3: Conception mode
Comparison 1: Live birth: assisted hatching compared with no assisted hatching, Outcome 4: Hatching method
Comparison 1: Live birth: assisted hatching compared with no assisted hatching, Outcome 5: Prognosis
Comparison 1: Live birth: assisted hatching compared with no assisted hatching, Outcome 6: Live birth rate by extent of assisted hatching
Comparison 1: Live birth: assisted hatching compared with no assisted hatching, Outcome 7: Fresh or frozen embryo transfer
Comparison 2: Multiple pregnancy: assisted hatching compared with no assisted hatching, Outcome 1: Multiple pregnancy rate per woman randomised
Comparison 2: Multiple pregnancy: assisted hatching compared with no assisted hatching, Outcome 2: First or repeat attempt
Comparison 2: Multiple pregnancy: assisted hatching compared with no assisted hatching, Outcome 3: Conception mode
Comparison 2: Multiple pregnancy: assisted hatching compared with no assisted hatching, Outcome 4: Hatching method
Comparison 2: Multiple pregnancy: assisted hatching compared with no assisted hatching, Outcome 5: Prognosis
Comparison 2: Multiple pregnancy: assisted hatching compared with no assisted hatching, Outcome 6: Multiple pregnancy rate per woman grouped by extent of assisted hatching
Comparison 2: Multiple pregnancy: assisted hatching compared with no assisted hatching, Outcome 7: Fresh or frozen embryo transfer
Comparison 2: Multiple pregnancy: assisted hatching compared with no assisted hatching, Outcome 8: Multiple pregnancy per pregnancy
Comparison 3: Clinical pregnancy: assisted hatching compared with no assisted hatching, Outcome 1: Clinical pregnancy rate per woman randomised
Comparison 3: Clinical pregnancy: assisted hatching compared with no assisted hatching, Outcome 2: First or repeat attempt
Comparison 3: Clinical pregnancy: assisted hatching compared with no assisted hatching, Outcome 3: Conception mode
Comparison 3: Clinical pregnancy: assisted hatching compared with no assisted hatching, Outcome 4: Hatching method
Comparison 3: Clinical pregnancy: assisted hatching compared with no assisted hatching, Outcome 5: Prognosis
Comparison 3: Clinical pregnancy: assisted hatching compared with no assisted hatching, Outcome 6: Extent of assisted hatching
Comparison 3: Clinical pregnancy: assisted hatching compared with no assisted hatching, Outcome 7: Fresh and frozen embryo transfer
Comparison 4: Clinical pregnancies in trials that reported live births: assisted hatching compared with no assisted hatching, Outcome 1: Clinical pregnancies in trials reporting live births
Comparison 5: Miscarriage: assisted hatching compared with no assisted hatching, Outcome 1: Miscarriage per woman randomised
Comparison 5: Miscarriage: assisted hatching compared with no assisted hatching, Outcome 2: First or repeat attempt
Comparison 5: Miscarriage: assisted hatching compared with no assisted hatching, Outcome 3: Conception mode
Comparison 5: Miscarriage: assisted hatching compared with no assisted hatching, Outcome 4: Hatching method
Comparison 5: Miscarriage: assisted hatching compared with no assisted hatching, Outcome 5: Prognosis
Comparison 5: Miscarriage: assisted hatching compared with no assisted hatching, Outcome 6: Miscarriage per clinical pregnancy
Comparison 6: Monozygotic twinning: assisted hatching compared with no assisted hatching, Outcome 1: Monozygotic twinning per woman randomised
Comparison 7: Robust studies (randomisation method and allocation concealment stated and live birth reported): assisted hatching compared with no assisted hatching, Outcome 1: Live births
Comparison 7: Robust studies (randomisation method and allocation concealment stated and live birth reported): assisted hatching compared with no assisted hatching, Outcome 2: Clinical pregnancies
| Assisted hatching compared to no assisted hatching for women undergoing assisted conception | ||||||
| Patient or population: women undergoing assisted conception Setting: clinic | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect | №. of participants | Quality of evidence | Comments | |
|---|---|---|---|---|---|---|
| Risk with no assisted hatching | Risk with assisted hatching | |||||
| Live births per woman randomised | 283 per 1000 | 301 per 1000 | OR 1.09 | 2849 | ⊕⊕⊝⊝ | |
| Multiple pregnancy rate per woman randomised | 91 per 1000 | 121 per 1000 | OR 1.38 | 4308 | ⊕⊕⊝⊝ | |
| Clinical pregnancy rate per woman randomised | 322 per 1000 | 363 per 1000 | OR 1.20 | 7249 | ⊕⊕⊝⊝ | |
| Miscarriage rate per woman randomised | 53 per 1000 | 60 per 1000 | OR 1.13 | 2810 | ⊕⊝⊝⊝ | |
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). | ||||||
| GRADE Working Group grades of evidence. | ||||||
| aDowngraded two levels for serious risk of bias and publication bias: in many studies, the method was unclear and information was incomplete. The main limitation was serious risk of bias associated with poor reporting of study methods. bDowngraded two levels for serious risk of bias and for serious inconsistency. cDowngraded three levels for serious risk of bias, serious inconsistency, and serious imprecision (only 158 events). | ||||||
| Study | AH n, mean age (SD) | Control n, mean age (SD) | OR for clinical pregnancy |
|---|---|---|---|
| 65, 39.2 (1.2) | 65, 39.5 (1.2) | 2.50 (1.14 to 5.49) | |
| Antinori 1999: first IVF | 73, 37.5 | 69, 36.0 | 1.27 (0.70 to 2.32) |
| Antinori 1999: repeat IVF | 96, 27.5 | 103, 27 | 1.86 (0.81 to 4.25) |
| 183, 32.4 (3.3) | 183, 32.7 (3.1) | 1.85 (1.19 to 2.86) | |
| 45, 32.5 (3.8) | 39, 33.8 (3.2) | 0.64 (0.27 to 1.55) | |
| 51, 31.8 (3.6) | 52, 31.4 (3.6) | 0.74 (0.33 to 1.65) | |
| 121, 34 (3.3) | 82, 34 (3.2) | 0.95 (0.54 to 1.67) | |
| 60, 33.1 (4.2) | 30, 34.0 (3.7) | 0.62 (0.26 to 1.49) | |
| Cohen 1992: FSH < 15 | 69, 36.50 (3.30) | 68, 36.70 (3.70) | 2.11 (1.18 to 3.77) |
| Cohen 1992: poor prognosis | 80, 36.7 (4.3) | 83, 35.3 (4.2) | 1.30 (0.66 to 2.55) |
| Cohen 1992: FSH > 15 | not stated | not stated | 1.30 (0.66 to 2.55) |
| not stated | not stated | 1.77 (0.52 to 6.01) | |
| 80, 31.0 (4.7) | 80, 31.7 (4.9) | 1.58 (0.81 to 3.08) | |
| 61, 32.3 (3.4) | 64, 32.1 (3.6) | 2.37 (1.07 to 5.28) | |
| Ge 2008: fresh embryo | 387, 31.08 (4.68) | 373, 30.44 (4.15) | 0.99 (0.74 to 1.32) |
| Ge 2008: frozen embryo | 100, 31.84 (3.85) | 100, 30.66 (4.42) | 2.05 (0.99 to 4.22) |
| Germond 2004: first cycle of frozen‐thawed embryos | 62, 32.8 (4.2) | 53, 32.6 (3.8) | 0.09 (0.01 to 0.76) |
| Germond 2004: poor prognosis, first cycle of fresh embryos | 22, 39.3 (2.9) | 21, 38.3 (3.4) | 0.51 (0.10 to 2.45) |
| 154, 38.5 (2.8) | 149, 37.3 (4.2) | 2.71 (1.62 to 4.56) | |
| 59, 32.1 (3.0) | 62, 31.2 (3.5) | 0.81 (0.37 to 1.76) | |
| 60, 30.9 (4.3) | 60, 30.8 (3.9) | 1.15 (0.55 to 2.43) | |
| 13, 30.0 (0.9) | 7, 30.0 (0.8) | 0.40 (0.06 to 2.89) | |
| 24, 30.5 (5.2) | 22, 29.1 (3.6) | 2.0 (0.62 to 6.49) | |
| not stated | not stated | 3.20 (0.91 to 11.27) | |
| 128, 32.3 (4.24) | 129, 32.1 (3.16) | 1.86 (1.12 to 3.10) | |
| Kutlu 2010: good prognosis | 73, 29.9 (2.9) | 66, 28.9 (3.4) | 1.06 (0.54 to 2.08) |
| Kutlu 2010: poor prognosis | 58, 38.0 (2.3) | 55, 37.4 (2.4) | 1.23 (0.58 to 2.60) |
| not stated | not stated | 0.85 (0.28 to 2.58) | |
| 41, 38.30 (0.31) | 48, 38.50 (0.26) | 0.90 (0.38 to 2.10) | |
| 158, 31.3 (4.1) | 150, 32.6 (2.4) | 1.79 (1.05 to 3.07) | |
| 20, 32.0 (4.0) | 20, 31.4 (3.7) | 8.0 (1.44 to 44.3) | |
| 80, 34.0 (range 25 to 40) | 80, 34.0 (range 26 to 40) | 0.81 (0.33 to 2.00) | |
| Petersen 2005: 1 previous implantation failure | 35, 34.6 (4.6) | 35, 34.1 (5.3) | 1.15 (0.41 to 3.19) |
| Petersen 2005: several previous implantation failures | 40, 35.7 (3.8) | 40, 35.3 (5.1) | 4.11 (1.04 to 16.29) |
| 90, 32.9 (0.5) | 92, 31.6 (0.4) | 0.7 (0.3 to 1.6) | |
| not stated | not stated | 0.72 (0.38 to 1.36) | |
| not stated | not stated | 0.74 (0.35 to 1.59) | |
| 30, 30.6 (5.6) | 32, 29.2 (5.3) | 0.58 (0.19 to 1.78) | |
| 118, 34.0 (3.3) | 81, 34.0 (3.2) | 0.94 (0.53 to1.65) | |
| 82, 37.2 (2.22) | 96, 36.97 (1.96) | 0.65 (0.36 to 1.18) | |
| not stated | not stated | 1.54 (0.67 to 3.54) | |
| 110, 34.1 (4.8) | 108, 34.2 (4.1) | 1.37 (0.79 to 2.35) | |
| 50, 35.3 (4.2) | 50, 33.5 (4.3) | 0.74 (0.35 to 1.59) | |
| not stated | not stated | 1.36 (0.32 to 5.73) | |
| 200, 30.86 (5.82) | 200, 29.85 (5.14) | 0.53 (0.35 to 0.80) | |
| 96, 33.1 (3.7) | 102, 32.6 (3.4) | 1.91 (1.08 to 3.38) |
| Study ID | Balanced age between groups | Balances no. of embryos transferred | Prognosis: poor/good | FSH levels | Blastocyst transfer | Complete/partial AH | Frozen cycles |
|---|---|---|---|---|---|---|---|
| Yes | Yes | Poor | No data | No | Thinning | Fresh | |
| AH mean 1.5 years older | Yes | Good and poor subgroups | No data | No | Complete hole | Not stated | |
| Yes | Yes | Unselected | < 10 | No | Thinning | Frozen | |
| AH mean 1.3 years older | Yes | Good | < 10 | No | Thinning | Fresh | |
| Yes | Yes | Good | No data | No | Thinning | Fresh | |
| Yes | Yes | Good | < 10 | No | Not stated | Fresh | |
| Yes | Yes | Good | < 15 | No | Thinning | Fresh | |
| Yes | Yes | Unstated | ≤ 15 and > 15 subgroups | No | Complete hole | Fresh | |
| Yes | No data | Poor | No data | No | Thinning | Frozen | |
| Yes | No data | Good | No data | No | Thinning | Frozen | |
| Yes | Yes | Not stated | No data | No | Mechanical expansion | Frozen thawed | |
| Yes | Yes | Mixed | No data | No | Thinning | Fresh and frozen subgroups | |
| Yes | Yes | Mixed, in subgroups | Between 3 and 12 | No | Complete hole | Fresh and frozen subgroups | |
| Yes | Yes | Poor | > 12 | No | Partial | Fresh | |
| Mean age data given only for combined cycles 1 and 2 | Yes | Under 38 years, > 2 previously failed cycles, ZP thickness > 13 micrometers | No data | No | 20 micrometer diameter opening | Fresh | |
| Yes | Yes | Good | No data | No | Complete hole | Fresh | |
| Yes | Yes | Good | < 10 | No | Complete hole | Fresh | |
| AH mean 1.4 years older | Yes | Unstated | < 10 | Yes | Removal complete | Fresh | |
| No data | Yes | Unstated | No data | Yes | Complete hole | Fresh | |
| Yes | Yes | Poor | No data | Yes | Removal complete | Fresh | |
| Yes | Yes | Good and poor subgroups | No data | No | Complete hole | Fresh | |
| No data | No data | Good | No data | No | Complete hole | Fresh | |
| No | Yes | Poor | No data | No | Complete hole | Fresh | |
| Yes | Yes | Good | AH 5.4 ± 1.3 | No | Thinning | Fresh | |
| Yes | Yes | Unstated | No data | No | Thinning | Frozen‐thaw cycle | |
| Yes | Higher proportion of controls received 3 embryos | Unstated | < 11 | No | Thinning | Frozen‐thaw cycle | |
| Yes | Yes | Poor | No data | No | Thinning | Fresh | |
| Yes | Yes | Unstated | No data | No | Partial | Fresh | |
| No data | Yes | Poor | No data | No | Complete hole | Fresh | |
| No data | No data | Unstated | No data | No | Complete hole | Both | |
| Yes | Yes | Unstated | AH 6.4 ± 2.3 No AH 5.6 ± 2.1 | No | Thinning | Frozen | |
| Yes | Yes | Good | < 10 | No | Hole | Fresh | |
| Yes | Yes | Advanced maternal age | < 10 | No | Zona Thinning | Fresh | |
| No data | No data | Poor | No data | No | Complete hole | Fresh | |
| Yes | Yes | Good | < 15 | No | Thinning | Fresh | |
| AH mean 1.8 years older | Yes | Not stated | No data | No | Complete hole | Fresh | |
| No data | No data | Poor | No data | No | Thinning | Fresh | |
| Yes | Yes | Not stated | No data | No | Partially thinned | Vitrified‐warmed embryo | |
| Yes | Yes | Previously unsuccessful 1 fresh cycle | No data | Yes | Partial | Vitrified‐warmed embryo | |
| AH: assisted hatching. | |||||||
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 1.1 Live birth per woman randomised Show forest plot | 14 | 2849 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.09 [0.92, 1.29] |
| 1.2 First or repeat attempt Show forest plot | 4 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 1.2.1 First attempt at IVF or ICSI | 3 | 380 | Odds Ratio (M‐H, Fixed, 95% CI) | 0.78 [0.48, 1.28] |
| 1.2.2 Repeat attempt at IVF or ICSI | 1 | 150 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.40 [0.62, 3.13] |
| 1.3 Conception mode Show forest plot | 6 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 1.3.1 ICSI only | 3 | 640 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.54 [1.02, 2.33] |
| 1.3.2 IVF only | 3 | 241 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.00 [0.60, 1.68] |
| 1.4 Hatching method Show forest plot | 14 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 1.4.1 Chemical | 4 | 366 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.13 [0.74, 1.74] |
| 1.4.2 Laser | 10 | 2473 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.07 [0.89, 1.28] |
| 1.5 Prognosis Show forest plot | 9 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 1.5.1 Poor prognosis | 4 | 576 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.46 [0.99, 2.15] |
| 1.5.2 Good prognosis | 6 | 1495 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.03 [0.83, 1.28] |
| 1.6 Live birth rate by extent of assisted hatching Show forest plot | 14 | 2849 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.09 [0.92, 1.29] |
| 1.6.1 Thinning only | 6 | 1742 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.06 [0.86, 1.30] |
| 1.6.2 Breach by hole only | 8 | 1107 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.15 [0.87, 1.51] |
| 1.7 Fresh or frozen embryo transfer Show forest plot | 12 | 1731 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.14 [0.92, 1.41] |
| 1.7.1 Fresh | 11 | 1669 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.16 [0.94, 1.44] |
| 1.7.2 Frozen | 1 | 62 | Odds Ratio (M‐H, Fixed, 95% CI) | 0.67 [0.22, 2.07] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 2.1 Multiple pregnancy rate per woman randomised Show forest plot | 18 | 4308 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.38 [1.13, 1.68] |
| 2.2 First or repeat attempt Show forest plot | 8 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 2.2.1 First attempt at IVF or ICSI | 4 | 654 | Odds Ratio (M‐H, Fixed, 95% CI) | 0.73 [0.31, 1.72] |
| 2.2.2 Repeat attempt at IVF or ICSI | 5 | 1068 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.25 [0.80, 1.94] |
| 2.3 Conception mode Show forest plot | 9 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 2.3.1 ICSI only | 3 | 573 | Odds Ratio (M‐H, Fixed, 95% CI) | 3.09 [1.57, 6.08] |
| 2.3.2 IVF only | 6 | 1126 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.87 [1.28, 2.72] |
| 2.4 Hatching method Show forest plot | 18 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 2.4.1 Chemical | 4 | 534 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.55 [0.98, 2.47] |
| 2.4.2 Laser | 13 | 3730 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.29 [1.03, 1.61] |
| 2.4.3 Mechanical | 1 | 44 | Odds Ratio (M‐H, Fixed, 95% CI) | 8.33 [1.56, 44.64] |
| 2.5 Prognosis Show forest plot | 10 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 2.5.1 Poor prognosis | 6 | 1186 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.95 [1.27, 3.00] |
| 2.5.2 Good prognosis | 6 | 1569 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.08 [0.81, 1.44] |
| 2.6 Multiple pregnancy rate per woman grouped by extent of assisted hatching Show forest plot | 16 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 2.6.1 Thinning only | 6 | 2148 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.34 [1.02, 1.76] |
| 2.6.2 Breach by hole | 9 | 1629 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.51 [1.08, 2.11] |
| 2.6.3 Complete removal of zona | 1 | 25 | Odds Ratio (M‐H, Fixed, 95% CI) | 0.62 [0.07, 5.28] |
| 2.7 Fresh or frozen embryo transfer Show forest plot | 16 | 3190 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.38 [1.08, 1.75] |
| 2.7.1 Fresh | 13 | 2264 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.30 [0.98, 1.73] |
| 2.7.2 Frozen | 3 | 926 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.60 [1.00, 2.55] |
| 2.8 Multiple pregnancy per pregnancy Show forest plot | 17 | 1598 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.37 [1.09, 1.72] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 3.1 Clinical pregnancy rate per woman randomised Show forest plot | 39 | 7249 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.20 [1.09, 1.33] |
| 3.2 First or repeat attempt Show forest plot | 18 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 3.2.1 First attempt at IVF or ICSI | 8 | 1010 | Odds Ratio (M‐H, Fixed, 95% CI) | 0.74 [0.56, 0.98] |
| 3.2.2 Repeat attempt at IVF or ICSI | 11 | 1798 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.65 [1.34, 2.04] |
| 3.3 Conception mode Show forest plot | 26 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 3.3.1 ICSI only | 11 | 1825 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.40 [1.14, 1.71] |
| 3.3.2 IVF only | 15 | 2460 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.31 [1.10, 1.55] |
| 3.4 Hatching method Show forest plot | 39 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 3.4.1 Chemical | 11 | 1536 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.33 [1.08, 1.64] |
| 3.4.2 Laser | 23 | 5127 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.15 [1.03, 1.30] |
| 3.4.3 Mechanical | 5 | 586 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.30 [0.89, 1.88] |
| 3.5 Prognosis Show forest plot | 24 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 3.5.1 Poor prognosis | 14 | 2108 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.68 [1.38, 2.04] |
| 3.5.2 Good prognosis | 14 | 2721 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.10 [0.94, 1.29] |
| 3.6 Extent of assisted hatching Show forest plot | 37 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 3.6.1 Thinning only | 17 | 3774 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.10 [0.96, 1.26] |
| 3.6.2 Breach by hole only | 17 | 2543 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.17 [0.98, 1.39] |
| 3.6.3 Complete removal of zona | 2 | 301 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.93 [1.21, 3.09] |
| 3.6.4 Expansion of zona pellucida | 1 | 125 | Odds Ratio (M‐H, Fixed, 95% CI) | 2.37 [1.07, 5.28] |
| 3.7 Fresh and frozen embryo transfer Show forest plot | 38 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 3.7.1 Fresh embryo transfer | 30 | 5349 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.23 [1.10, 1.38] |
| 3.7.2 Frozen embryo transfer only | 10 | 1700 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.15 [0.93, 1.42] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 4.1 Clinical pregnancies in trials reporting live births Show forest plot | 14 | 2849 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.07 [0.92, 1.25] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 5.1 Miscarriage per woman randomised Show forest plot | 17 | 2810 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.13 [0.82, 1.56] |
| 5.2 First or repeat attempt Show forest plot | 8 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 5.2.1 First attempt at IVF or ICSI | 4 | 442 | Odds Ratio (M‐H, Fixed, 95% CI) | 0.98 [0.51, 1.89] |
| 5.2.2 Repeat attempt at IVF or ICSI | 5 | 966 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.96 [0.90, 4.28] |
| 5.3 Conception mode Show forest plot | 10 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 5.3.1 ICSI only | 4 | 665 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.20 [0.58, 2.47] |
| 5.3.2 IVF only | 6 | 896 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.28 [0.65, 2.52] |
| 5.4 Hatching method Show forest plot | 17 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 5.4.1 Chemical | 5 | 412 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.11 [0.56, 2.21] |
| 5.4.2 Laser | 11 | 2244 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.13 [0.78, 1.64] |
| 5.4.3 Mechanical | 1 | 154 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.14 [0.07, 18.58] |
| 5.5 Prognosis Show forest plot | 11 | Odds Ratio (M‐H, Fixed, 95% CI) | Subtotals only | |
| 5.5.1 Poor prognosis | 7 | 1133 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.21 [0.70, 2.08] |
| 5.5.2 Good prognosis | 5 | 626 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.03 [0.50, 2.14] |
| 5.6 Miscarriage per clinical pregnancy Show forest plot | 15 | 777 | Odds Ratio (M‐H, Random, 95% CI) | 0.94 [0.62, 1.43] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 6.1 Monozygotic twinning per woman randomised Show forest plot | 6 | 729 | Odds Ratio (M‐H, Fixed, 95% CI) | 3.23 [0.34, 31.03] |
| Outcome or subgroup title | No. of studies | No. of participants | Statistical method | Effect size |
| 7.1 Live births Show forest plot | 1 | 960 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.08 [0.82, 1.41] |
| 7.2 Clinical pregnancies Show forest plot | 1 | 960 | Odds Ratio (M‐H, Fixed, 95% CI) | 1.10 [0.85, 1.43] |
