Table 1. Characteristics of the studies included.
Author Country Study Period Design Intervention Control Group Study Group  
Baart et al., 2007 Netherlands Dec'02-Aug'05 RCT Low vs. Conventional Stimulation 150 IU / antagonist 225 IU / long agonist  
Weghofer et al., 2008 Austria/USA Jan'04-Jun'05 Retrospective FSH vs. LH-containing gonadotropins/agonist protocol FSH hMG  
Verpoest et al., 2008 Belgium Oct'05-Apr'06 Prospective observational study Aneuploidy in Unstimulated Cycles No control group Unstimulated cycles  
Haaf et al., 2009 Germany Jan'02-Dec'05 Retrospective Oocyte aneuploidy by age and response (1-5, 6-10, or >10 oocytes) <35 years 35-40 years; >40 years  
Weghofer et al., 2009 Austria/USA Jan'03-Jun'05 Retrospective FSH vs. LH-containing gonadotropins/antagonist protocol FSH hMG  
Rubio et al., 2010 Spain NA Crossover study 1st cycle normal dose vs. 2nd cycle 30% reduce dose, 3 months apart 225 IU/long agonist 150 UI/antagonist  
Kyrou et al., 2011 Belgium Oct'92-Dic'06 Retrospective GnRH agonist vs. GnRH Antagonist Agonist Antagonist  
Massie et al., 2011 USA Jan'99-Aug'07 Retrospective Aneuploidy in miscarriages from stimulation vs. no stimulation Natural conceptions Stimulation  
Ata et al., 2012 USA Jan'10-Jul'11 Retrospective Aneuploidy according to embryos biopsied NA NA  
Labarta et al., 2012 Spain Sep'06-Mar'10 Prospective crossover study 1st cycle unstimulated vs. 2nd cycle stimulated, same patient Unstimulated Stimulated with 225 IU  
Sekhon et al., 2017 USA Mar'10-Apr'15 Retrospective Cumulative dose and aneuploidy rate NA NA  
Labarta et al., 2017 Spain Sep'06-Mar'10 Post hoc analysis of prospective crossover study Aneuploidy according to ovarian response (same-dosage): low vs. high Low: <17 oocytes High: ≥17 oocytes  
Barash et al., 2017 USA Jan'13-Jan'13 Retrospective Different dosages of gonadotropins and aneuploidy rate NA NA  
Venetis et al., 2019 Australia Mar’11-Dec’16 Retrospective, Multicenter Correlation of oocytes retrieved and the number of euploid embryos NA NA  
Thorne et al., 2019 USA Jan’13-Feb’18 Retrospective Final oocyte maturation trigger rhCG vs. aGnRH rhCG trigger aGnRH trigger  
Author Inclusion Criteria Patients Patients by Group PGT platform Biopsy Day Cells Biopsied Cells Biopsied
Baart et al., 2007 General IVF patients, regular menses, 5 mill sperm, 46XX 111 Low=67
High=44
FISH (10 chromosomes) Day 3 Cells Biopsied Low=33.2
High=34.1
Weghofer et al., 2008 General IVF patients, regular menses, normal ovarian function, 46XX 104 FSH=52
hMG=52
FISH (9 chromosomes) Day 3 1-2 cells FSH=35.0
hMG=35.9
Verpoest et al., 2008 Regular menses, <3 failed cycles, normal uterine cavity 30 Unstimulated=30 FISH (5 chromosomes) Day 3 1 cell 31.4
Haaf et al., 2009 >35 years or previous IVF cycle with no ET 30 <35: 93 cycles
35-40: 376 cycles
>40: 165 cycles
FISH (5 chromosomes) Day 0 1 cell NA
Weghofer et al., 2009 General IVF patients, regular menses, normal ovarian function, 46XX 104 FSH=52, hMG=52 FISH (9 chromosomes) Day 3 2 cells FSH=39.8
hMG=39.6
Rubio et al., 2010 Oocyte donors 32 First cycle= 32
Second cycle=22
(10 no biopsy)
FISH (9 chromosomes) Day 3 1 cell 22.0
Kyrou et al., 2011 Recurrent Miscarriage, RIF, azoospermia 694 Agonist=320
Antagonist=374
FISH (7 Cells Biopsied) Day 3 1-2 cells Agonist=32.8
Antagonist=32.7
Massie et al., 2011 Infertility patients trying to conceive 229 No stimulation=50
FSH for IUI=35
FSH for IVF=144
Trypsin-Wright G-banding NA 1 cell Natural 37.0
FSH exposure 37.0
Ata et al., 2012 Infertility patients undergoing PGT or Oocyte donors 990 7753 embryos aCGH-based CCS Day 3/Day 5 POCs NA
Labarta et al., 2012 Oocyte donors 232 Unstimulated=185
Stimulated=47
FISH (9 chromosomes) Day 3 Day 3: 1-2 cells;
Day 5: 3-10 cells
25.4
Sekhon et al., 2017 Infertility patients undergoing PGT 828 1122 cycles qPCR-based CCS Day 5 1 cell 38.5
Labarta et al., 2017 Oocyte donors 46 Low response=22
High response=24
FISH (9 chromosomes) Day 3 4-7 cells Low=25.6
High=24.9
Barash et al., 2017 Infertility patients undergoing PGT 681 794 cycles SNP Day 5 4-9 cells NA
Venetis et al., 2019 Infertility patients undergoing PGT 724 724 cycles aCGH Day 3 1 cell NA
Thorne et al., 2019 Infertility patients undergoing PGT 539 hCG trigger=336
aGnRH
trigger=203
aCGH/NGS Day 5 NA No restriction
Author Primary Outcome measure Oocytes retrieved Aneuploidy Rate per embryo Aneuploidy Rate by ITT Euploid Embryos (n) Euploid Embryos by ITT (n)  
Baart et al., 2007 Oocytes retrieved
Aneuploidy Rate
Low=8.2
High=12.1
Low=50%
High=62%, p=0.48
Low=22%
High=26%, p=0.4
Low=1.8
High=1.8
Low=1.4
High=2.5
 
Weghofer et al., 2008 Oocytes retrieved
Aneuploidy Rate
FSH=23.7
hMG=20.3
FSH=54.7%
hMG=30.2%, p<0.01
Only patients with biopsy included FSH=3.1
hMG=3.3
NA  
Verpoest et al., 2008 Aneuploidy Rate Unstimulated =0.6 Unstimulated=36.4% NA Unstimulated =0.2 NA  
Haaf et al., 2009 Aneuploidy per cohort size (1-5,6-10, >10 oocytes) and per age (<35, 35–40, >40) <35: 8.5
35-40: 8.6
>40: 7.1
1-5 oocytes (<35: 23.3%; 35-40:41.2%; >40:49.6%) 6-10 oocytes (<35:34.9%; 35-40: 43.8%; >40: 50.0%) >10 oocytes (<35:50.9%; 35-40:54.6%; >40:54.1%) NA NA NA  
Weghofer et al., 2009 Oocytes retrieved
Aneuploidy Rate
FSH=15.2
hMG=13.8
FSH=70.6%
hMG=74.3%, NS
NA (only patients with biopsy included) FSH=2.1
hMG=1.9
NA  
Rubio et al., 2010 Oocytes retrieved
Aneuploidy Rate
Standard=23.9
Reduced=14.7
Standard=83.9%
Reduced=77.5%
NA Standard=3.1
Reduced=2.7
Standard=3.1
Reduced=1.8
 
Kyrou et al., 2011 Oocytes retrieved
Aneuploidy Rate
Agonist=12.9
Antagonist=13.6
Agonist=49.9%
Antagonist 50.2%, p=0.922
NA (only patients with biopsy included) Agonist=2.7
Antagonist=3.1
NA  
Massie et al., 2011 Aneuploid gestation NA Natural=70%
FSH exposure=63%, NS
NA NA NA  
Ata et al., 2012 Aneuploidy per cohort size (1-4, 5-7, 8-10, >10 embryos) and per age (<35, 35–39, 40–42, ≤43) NA Per age and (D3/Blastocyst): <35 (38.3%/61.4%) 35–39 (28.9%/50.27%) 40–42 (16.05% /33.37%); ≤43 (8.95%/17.3%) NA NA NA  
Labarta et al., 2012 Aneuploidy Rate Unstimulated =0.8
Stimulated=17.8
Unstimulated=35.3% vs. Stimulated=40.6% Unstimulated =76.7%
Stimulated =40.6%
Unstimulated =1.8
Stimulated=3.9
Unstimulated =1.0
Stimulated=3.9
 
Sekhon et al., 2017 Cumulative gonadotropin dose used, duration of stimulation NA 47% no association of cumulative dose and aneuploidy (adjusted OR=1.0.49, p=0.232) NA NA NA  
Labarta et al., 2017 Number of euploid embryos Low=11.5
High=23.8
Low=39%
High=639%, p=0.2
NA Low=2.7 .
High=5.0
NA  
Barash et al., 2017 Aneuploidy Rate per dosage and per age 16,3 <35 years old: 62.86%
35–37 years old:
55.75%
38-40 years old:
42.23%
>41 years old: 27.53%
NA NA NA  
Venetis et al., 2019 Number of euploid embryos 11.7 (11.1–12.2) Euploidy 17.4% (15.5–19.3), Aneuploidy 82.6% NA 1.0 (0.9–1.1) NA  
Thorne et al., 2019 Aneuploidy Rate hCG=11.5
aGnRH=19.3
hCG=30.3% vs . aGnRH=37.8%
MLRA: no differences between groups
NA NA NA  

*RCT: randomized controlled trial; IU: international units; USA: United States of America; FSH: follicle stimulating hormone; LH: luteinizing hormone; hMG: human menopausal gonadotropins; NA: not applicable; GnRH: gonadotropin-releasing hormone; rhCG: recombinant human chorionic gonadotropin; aGnRH: agonist of the GnRH; IVF: in vitro fertilization; FISH: Fluorescence in situ hybridization; RIF: repeated implantation failure; IUI: intrauterine insemination; POCs: products of conception; PGT: preimplantation genetic testing; array comparative genomic hybridization; qPCR-based CCS: quantitative polymerase chain reaction – based comprehensive chromosome screening; SNPs: single nucleotide polymorphism; NGS: next-generation sequencing; ITT: intention-to-treat; D3: cleavage-stage embryo.