Table 1.
Characteristics of included studies.
| Study | Country | Study period | Study design | Study groups (n) | Patients’ Age (y, Mean ± SD) | Patients’ BMI (Mean ± SD) | Fertilization method | Cycle Type | RIF | Note |
|---|---|---|---|---|---|---|---|---|---|---|
| Antonio Sanoja Breña. (2016) | Spanish | 2012.09–2014.09 | CCT (RC) | D3/D5-6 sequential transfer (58) D3 single transfer (118) D5-6 single transfer (26) D3 double transfer (236) D5-6 double transfer (33) D3 triple transfer (316) |
D3/D5-6 sequential transfer (36.34 ± 4.78) The age of the remaining five groups of patients is unknown. |
N/A | IVF/ICSI | Fresh-ET | No | |
| B Almog et al. (2008) | Israel | 2003.03–2005.05 | CCT (RC) | D2-3/D5 consecutive transfer (65) D2-3 embryo transfer (66) |
D2-3/D5 consecutive transfer (34.3 ± 0.7) D2-3 embryo transfer (34.7 ± 0.1) |
N/A | IVF/ICSI | Fresh-ET | Yes | The number of embryos transferred per patient is uncertain. |
| Chadi Yazbeck et al. (2013) | France | 2005.01–2006.12 | CCT (RC) | D2-3/D5-6 consecutive transfer (120) D2-3 embryo transfer (280) |
D2-3/D5-6 consecutive transfer (33.07 ± 4.13) The age of the patients in D2-3 embryo transfer group is uncertain. |
N/A | IVF/ICSI | Fresh-ET | No | The number of embryos transferred per patient is uncertain. |
| Cong Fang et al. (2013) | China | 2010.08–2011.12 | CCT (RC) | D2/D3 sequential transfer (33) D3/D5 sequential transfer (57) D3 embryo transfer (85) D5 blastocyst transfer (24) |
D2/D3 sequential transfer (35.1 ± 4.1) D3/D5 sequential transfer (34.1 ± 3.2) D3 embryo transfer (33.9 ± 4.1) D5 embryo blastocyst (33.1 ± 4.5) |
N/A | IVF/ICSI | Fresh-ET | Yes | Exclude data from the D2/D3 sequential transfer group. The number of embryos transferred per patient is uncertain. |
| Ensieh Shahrokh Tehraninejad et al. (2019) | Iran | 2016.04–2017-04 | RCT (PC) | D3/D5 sequential transfer (60) D5 blastocyst transfer (60) |
D3/D5 sequential transfer (35.03 ± 4.35) D5 blastocyst transfer (34.09 ± 4.20) |
N/A | ICSI | Fresh-ET | Yes | Three embryos were transferred to patients in D3/D5 sequential transfer group, and two embryo was transferred to patients in D5 embryo transfer group. |
| J Ashkenazi et al. (2000) | Israel | 1997.10–1998.12 | CCT (RC) | D2/D3 sequential transfer (107) D2-3/D5-6 sequential transfer (29) D2-3 embryo transfer (139) |
D2/D3 sequential transfer (31.1 ± 4.9) D2-3/D5-6 sequential transfer (29.5 ± 2.9) D2-3 embryo transfer (32.2 ± 5.6) |
N/A | IVF/ICSI | Fresh-ET | No | Exclude data from the D2/D3 sequential transfer group. Three embryos were transferred to patients in D2-3/D5-6 sequential transfer group and D2-3 embryo transfer group. |
| Kaya Gözde et al. (2020) | Turkey | 2011.01–2014.01 | CCT (RC) | D2/D3 consecutive transfer (54) D3/D5 consecutive transfer (53) D2-3 double transfer (135) |
D2/D3 consecutive transfer (32.0(28.7–35.0)) D3/D5 consecutive transfer (29.0 (26.0–33.7)) D2-3 double transfer (31.0 (28.0–35.0)) |
D2/D3 consecutive transfer (25.2 ± 5.2) D3/D5 consecutive transfer (24.6 ± 4.0) D2-3 double transfer (24.4 ± 4.2) |
ICSI | Fresh-ET | No | Exclude data from the D2/D3 sequential transfer group. All patients included in the study were transferred two embryos. |
| Koichi Kyono et al. (2003) | Japan | 2001.01–2002.12 | CCT (RC) | D3/D5 sequential transfer (125) D3 embryo transfer (523) D5 blastocyst transfer (87) |
D3/D5 sequential transfer (35.4 ± 4.5) D3 embryo transfer (35.5 ± 4.8) D5 blastocyst transfer (35.5 ± 4.5) |
N/A | IVF/ICSI | Fresh-ET | Yes | The number of embryos transferred per patient is uncertain. |
| Mengxia Ji et al. (2022) | China | 2017.01–2021.07 | CCT (RC) | D3/D5 sequential transfer (77) D3 embryo transfer (154) D5 blastocyst transfer (80) |
D3/D5 sequential transfer (33.39 ± 3.89) D3 embryo transfer (33.63 ± 3.97) D5 blastocyst transfer (32.50 ± 3.79) |
D3/D5 sequential transfer (21.38 ± 2.72) D3 embryo transfer (21.53 ± 2.61) D5 blastocyst transfer (21.16 ± 2.65) |
N/A | FET | Yes | All patients included in the study were transferred two embryos. |
| Ronit Machtinger et al. (2006) | Israel | 1999.01–2004.05 | CCT (RC) | D3/D5-6 sequential transfer (66) D3 embryo transfer (117) |
D3/D5-6 sequential transfer (30.7 ± 3.2) D3 embryo transfer (31.0 ± 2.9) |
N/A | IVF/ICSI | Fresh-ET/ FET | Yes | The number of embryos transferred per patient is uncertain. |
| S al-Hasani et al. (1990) | Germany | N/A | CCT (RC) | D2/D5 sequential transfer (38) D2 embryo transfer (68) |
N/A | N/A | N/A | Fresh-ET | No | Four or five embryos were transferred to patients in D2/D5 sequential transfer group, and three embryo was transferred to patients in D2 embryo transfer group. |
| Saghar Salehpour et al. (2023) | Iran | N/A | RCT (PC) | D3/D5 sequential embryo transfer (102) D5 double blastocyst transfer (100) |
D3/D5 sequential embryo transfer (33.92 ± 0.4794) D5 double blastocyst transfer (34.90 ± 0.5192) |
D3/D5 sequential embryo transfer (26.93 ± 0.2366) D5 double blastocyst transfer (26.47 ± 0.2350) |
ICSI | FET | Yes | All patients included in the study were transferred two embryos. |
| Sakae Goto et al. (2005) | Japan | 2000.04–2003.12 | CCT (RC) | D2/D5 consecutive transfer (51) D2 embryo transfer (90) |
D2 embryo transfer (37.7 ± 4.8) The age of the patients in D2/D5 consecutive transfer group is uncertain. |
N/A | IVF/ICSI | Fresh-ET | No | Patients in the consecutive transfer group who did not undergo a second transfer because no blastocysts were obtained were excluded. All patients included in the study were transferred two embryos. |
| Simon J Phillips et al. (2003) | Canada | 2001.01–2002.07 | CCT (RC) | D3/D5 consecutive transfer (110) D3 single transfer (32) |
consecutive transfer (34.7 ± 3.48) D3 single transfer (35 ± 4.36) |
N/A | IVF/ICSI | Fresh-ET | No | Two embryos were transferred to patients in D3/D5 consecutive transfer group, and one embryo was transferred to patients in D3 single transfer group. |
| Soheila Arefi et al. (2022) | Iran | 2020.01–2021.09 | RCT (PC) | D3/D5 sequential transfer (100) D5 blastocyst transfer (100) |
D3/D5 sequential transfer (35.06 ± 4.33) D5 blastocyst transfer (33.90 ± 4.00) |
D3/D5 sequential transfer (25.95 ± 3.75) D5 blastocyst transfer (25.83 ± 3.01) |
ICSI | FET | Yes | Two or three embryos were transferred to patients in D3/D5 sequential transfer group, and two embryo was transferred to patients in D5 embryo transfer group. |
| Wael A. Ismail Madkour et al. (2015) | Egypt | 2008.04–2011.03 | RCT (PC) | D3/D5 sequential transfer (74) D3 embryo transfer (73) |
D3/D5 sequential transfer (34.4 ± 1.4) D3 embryo transfer (34.0 ± 1.5) |
D3/D5 sequential transfer (23.47 ± 7.92) D3 embryo transfer (21.98 ± 5.86) |
ICSI | Fresh-ET | Yes | All patients included in the study were transferred three embryos. |
CCT, case–control trial; ET, embryo transfer; FET, frozen embryo transfer; ICSI, intracytoplasmic sperm injection; IVF, in vitro fertilization; PC, prospective cohort; RC, retrospective cohort; RCT, randomized controlled trial; RIF, repeated implantation failure.