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Time-lapse systems for embryo incubation and assessment in assisted reproduction. BACKGROUND: Embryo incubation and assessment is a vital step in assisted reproductive technology (ART). Traditionally, embryo assessment has been achieved by removing embryos from a conventional incubator daily for quality assessment by an embryologist, under a microscope. In recent years time-lapse systems (TLS) have been developed which can take digital images of embryos at frequent time intervals. This allows embryologists, with or without the assistance of embryo selection software, to assess the quality of the embryos without physically removing them from the incubator.The potential advantages of a TLS include the ability to maintain a stable culture environment, therefore limiting the exposure of embryos to changes in gas composition, temperature, and movement. A TLS has the potential advantage of improving embryo selection for ART treatment by utilising additional information gained through continuously monitoring embryo development. Use of a TLS often adds significant extra cost to ART treatment. OBJECTIVES: To determine the effect of a TLS compared to conventional embryo incubation and assessment on clinical outcomes in couples undergoing ART. SEARCH METHODS: We used standard methodology recommended by Cochrane. We searched the Cochrane Gynaecology and Fertility (CGF) Group Trials Register, CENTRAL, MEDLINE, Embase, CINAHL, and two trials registers on 7 January 2019 and checked references of appropriate papers. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing TLS, with or without embryo selection software, versus conventional incubation with morphological assessment; and TLS with embryo selection software versus TLS without embryo selection software among couples undergoing ART. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures recommended by Cochrane. The primary review outcomes were live birth or ongoing pregnancy, miscarriage and stillbirth, and cumulative live birth or ongoing pregnancy rate. The secondary outcomes were clinical pregnancy and cumulative clinical pregnancy. We assessed the quality of the evidence using GRADE methodology. We made the following comparisons.TLS with conventional morphological assessment of still TLS images versus conventional incubation and assessmentTLS utilising embryo selection software versus TLS with conventional morphological assessment of still TLS images TLS utilising embryo selection software versus conventional incubation and assessment MAIN RESULTS: We included nine RCTs (N = 2955 infertile couples). The quality of the evidence ranged from very low to low. The main limitations were high risk of bias in the included studies, imprecision, indirectness, and inconsistency. There were no data on cumulative live birth or ongoing pregnancy rate or cumulative clinical pregnancy rate.TLS with conventional morphological assessment of still TLS images versus conventional incubation and assessmentIt is unclear whether there is any difference between interventions in rates of live birth or ongoing pregnancy (odds ratio (OR) 0.91, 95% confidence interval (CI) 0.67 to 1.23, 3 RCTs, N = 826, I2 = 33%, low-quality evidence) or in miscarriage rates (OR 1.90, 95% CI 0.99 to 3.61, 3 RCTs, N = 826, I2 = 0%, low-quality evidence). The evidence suggests that if the rate of live birth or ongoing pregnancy associated with conventional incubation and assessment is 35%, the rate with the use of TLS with conventional morphological assessment of still TLS images would be between 27% and 40%, and if the miscarriage rate with conventional incubation is 4%, the rate associated with conventional morphological assessment of still TLS images would be between 4% and 14%. It is unclear whether there is a difference between the interventions in rates of stillbirth (OR 1.00, 95% CI 0.13 to 7.49, 1 RCT, N = 76, low-quality evidence) or clinical pregnancy (OR 1.06, 95% CI 0.79 to 1.41, 4 RCTs, N = 875, I2 = 0%, low-quality evidence).TLS utilising embryo selection software versus TLS with conventional morphological assessment of still TLS imagesAll findings for this comparison were very uncertain due to the very low-quality of the evidence. No data were available on live birth, but one RCT reported ongoing pregnancy. It is unclear whether there is any difference between the interventions in rates of ongoing pregnancy (OR 0.61, 95% CI 0.32 to 1.20, 1 RCT, N = 163); miscarriage (OR 1.39, 95% CI 0.64 to 3.01, 2 RCTs, N = 463, I2 = 0%); or clinical pregnancy (OR 0.97, 95% CI 0.67 to 1.42, 2 RCTs, N = 463, I2 = 0%). The evidence suggests that if the rate of ongoing pregnancy associated with TLS with conventional morphological assessment of still TLS images is 47%, the rate associated with TLS utilising embryo selection software would be between 22% and 52%, and if the miscarriage rate associated with conventional morphological assessment of still TLS images is 5%, the rate associated with TLS utilising embryo selection software would be between 4% and 15%. No studies reported stillbirth.TLS utilising embryo selection software versus conventional incubation and assessmentThe findings for this comparison were also very uncertain due to the very low quality of the evidence. It is unclear whether there is any difference between the interventions in rates of live birth (OR 1.12, 95% CI 0.92 to 1.36, 3 RCTs, N = 1617, I2 = 84%). There was very low-quality evidence that TLS might reduce miscarriage rates (OR 0.63, 95% CI 0.45 to 0.89, 3 RCTs, N = 1617, I2 = 0%). It is unclear whether there is any difference between the interventions in rates of clinical pregnancy (OR 0.95, 95% CI 0.78 to 1.16, 3 RCTs, N = 1617, I2 = 89%). The evidence suggests that if the rate of live birth associated with conventional incubation and assessment is 48%, the rate with TLS utilising embryo selection software would be between 46% and 55%, and if the miscarriage rate with conventional incubation and assessment is 11%, the rate associated with TLS would be between 5% and 10%. No stillbirths occurred in the only study reporting this outcome. AUTHORS' CONCLUSIONS: There is insufficient good-quality evidence of differences in live birth or ongoing pregnancy, miscarriage and stillbirth, or clinical pregnancy to choose between TLS, with or without embryo selection software, and conventional incubation. As the evidence is of low or very low-quality, our findings should be interpreted with caution.

Time-lapse systems for embryo incubation and assessment in assisted reproduction. BACKGROUND: Embryo incubation and assessment is a vital step in assisted reproductive technology (ART). Traditionally, embryo assessment has been achieved by removing embryos from a conventional incubator daily for quality assessment by an embryologist, under a light microscope. Over recent years time-lapse systems have been developed which can take digital images of embryos at frequent time intervals. This allows embryologists, with or without the assistance of embryo selection software, to assess the quality of the embryos without physically removing them from the incubator.The potential advantages of a time-lapse system (TLS) include the ability to maintain a stable culture environment, therefore limiting the exposure of embryos to changes in gas composition, temperature and movement. A TLS has the potential advantage of improving embryo selection for ART treatment by utilising additional information gained through continuously monitoring embryo development. Use of a TLS often adds significant extra cost onto an in vitro fertilisation (IVF) cycle. OBJECTIVES: To determine the effect of a TLS compared to conventional embryo incubation and assessment on clinical outcomes in couples undergoing ART. SEARCH METHODS: We used standard methodology recommended by Cochrane. We searched the Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, CINAHL and two trials registers on 2 August 2017. SELECTION CRITERIA: We included randomised controlled trials (RCTs) in the following comparisons: comparing a TLS, with or without embryo selection software, versus conventional incubation with morphological assessment; and TLS with embryo selection software versus TLS without embryo selection software among couples undergoing ART. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures recommended by Cochrane. The primary review outcomes were live birth, miscarriage and stillbirth. Secondary outcomes were clinical pregnancy and cumulative clinical pregnancy. We reported quality of the evidence for important outcomes using GRADE methodology. We made the following comparisons.TLS with conventional morphological assessment of still TLS images versus conventional incubation and assessmentTLS utilising embryo selection software versus TLS with conventional morphological assessment of still TLS images TLS utilising embryo selection software versus conventional incubation and assessment MAIN RESULTS: We included eight RCTs (N = 2303 women). The quality of the evidence ranged from very low to moderate. The main limitations were imprecision and risk of bias associated with lack of blinding of participants and researchers, and indirectness secondary to significant heterogeneity between interventions in some studies. There were no data on cumulative clinical pregnancy.TLS with conventional morphological assessment of still TLS images versus conventional incubation and assessmentThere is no evidence of a difference between the interventions in terms of live birth rates (odds ratio (OR) 0.73, 95% CI 0.47 to 1.13, 2 RCTs, N = 440, I2 = 11% , moderate-quality evidence) and may also be no evidence of difference in miscarriage rates (OR 2.25, 95% CI 0.84 to 6.02, 2 RCTs, N = 440, I2 = 44%, low-quality evidence). The evidence suggests that if the live birth rate associated with conventional incubation and assessment is 33%, the rate with use of TLS with conventional morphological assessment of still TLS images is between 19% and 36%; and that if the miscarriage rate with conventional incubation is 3%, the rate associated with conventional morphological assessment of still TLS images would be between 3% and 18%. There is no evidence of a difference between the interventions in the stillbirth rate (OR 1.00, 95% CI 0.13 to 7.49, 1 RCT, N = 76, low-quality evidence). There is no evidence of a difference between the interventions in clinical pregnancy rates (OR 0.88, 95% CI 0.58 to 1.33, 3 RCTs, N = 489, I2 = 0%, moderate-quality evidence).TLS utilising embryo selection software versus TLS with conventional morphological assessment of still TLS imagesNo data were available on live birth or stillbirth. We are uncertain whether TLS utilising embryo selection software influences miscarriage rates (OR 1.39, 95% CI 0.64 to 3.01, 2 RCTs, N = 463, I2 = 0%, very low-quality evidence) and there may be no difference in clinical pregnancy rates (OR 0.97, 95% CI 0.67 to 1.42, 2 RCTs, N = 463, I2 = 0%, low-quality evidence). The evidence suggests that if the miscarriage rate associated with assessment of still TLS images is 5%, the rate with embryo selection software would be between 3% and 14%.TLS utilising embryo selection software versus conventional incubation and assessmentThere is no evidence of a difference between TLS utilising embryo selection software and conventional incubation improving live birth rates (OR 1.21, 95% CI 0.96 to 1.54, 2 RCTs, N = 1017, I2 = 0%, very low-quality evidence). We are uncertain whether TLS influences miscarriage rates (OR 0.73, 95% CI 0.49 to 1.08, 3 RCTs, N = 1351, I2 = 0%, very low-quality evidence). The evidence suggests that if the live birth rate associated with no TLS is 38%, the rate with use of conventional incubation would be between 36% and 58%, and that if miscarriage rate with conventional incubation is 9%, the rate associated with TLS would be between 4% and 10%. No data on stillbirths were available. It was uncertain whether the intervention influenced clinical pregnancy rates (OR 1.17, 95% CI 0.94 to 1.45, 3 RCTs, N = 1351, I2 = 42%, very low-quality evidence). AUTHORS' CONCLUSIONS: There is insufficient evidence of differences in live birth, miscarriage, stillbirth or clinical pregnancy to choose between TLS, with or without embryo selection software, and conventional incubation. The studies were at high risk of bias for randomisation and allocation concealment, the result should be interpreted with extreme caution.

Time-lapse systems for embryo incubation and assessment in assisted reproduction. BACKGROUND: Embryo incubation and assessment is a vital step in assisted reproductive technology (ART). Traditionally, embryo assessment has been achieved by removing embryos from a conventional incubator daily for assessment of quality by an embryologist, under a light microscope. Over recent years time-lapse systems (TLSs) have been developed which can take digital images of embryos at frequent time intervals. This allows embryologists, with or without the assistance of computer algorithms, to assess the quality of the embryos without physically removing them from the incubator.The potential advantages of a TLS include the ability to maintain a stable culture environment, therefore limiting the exposure of embryos to changes in gas composition, temperature and movement. Additionally a TLS has the potential advantage of improving embryo selection for ART treatment by utilising additional information gained through monitoring embryo development. OBJECTIVES: To determine the effect of a TLS compared to conventional embryo incubation and assessment on clinical outcomes in couples undergoing ART. SEARCH METHODS: A comprehensive search of all the major electronic databases, including grey literature, was undertaken in co-ordination with the Trials Search Co-ordinator of the Cochrane Menstrual Disorders and Subfertility Group in July 2014 and repeated in November 2014 to confirm that the review is up to date. SELECTION CRITERIA: Two authors (SA and NA) independently scanned the titles and abstracts of the articles retrieved by the search. Full texts of potentially eligible randomised controlled trials (RCTs) were obtained and examined independently by the authors for their suitability according to the review inclusion criteria. In the case of doubt between the two authors, a third author (LC) was consulted to gain consensus. The selection process is documented with a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow chart. DATA COLLECTION AND ANALYSIS: Data were obtained and extracted by two authors. Disagreement was resolved by consensus. Trial authors were contacted by e-mail to obtain further study information and data. All extracted data were dichotomous outcomes and odds ratios (OR) were calculated on an intention-to-treat basis. Where enough data were available, meta-analysis was undertaken. MAIN RESULTS: Three studies involving 994 women were found for inclusion. Data from all three studies were used to address comparison one, TLS with or without cell-tracking algorithms versus conventional incubation. No studies were found to address comparison two, TLS utilising cell-tracking algorithms versus TLS not utilising cell-tracking algorithms.There was only one study which reported live birth (n = 76). The results demonstrated no conclusive evidence of a difference in live birth rate per couple randomly assigned to the TLS and conventional incubation arms of the study (OR 1.1, 95% CI 0.45 to 2.73, 1 RCT, n = 76, moderate quality evidence).All three studies reported miscarriage (n = 994). There was no conclusive evidence of a difference in miscarriage rates per couple randomly assigned to the TLS and conventional incubation arms (OR 0.70, 95% CI 0.47 to 1.04, 3 RCTs, n = 994, I(2) = 0%, low quality evidence).Only one study reported stillbirth rates (n = 76). There were equal numbers of stillbirths in both the TLS and conventional incubation arms of the study. Therefore, there was no evidence of a difference in the stillbirth rate per couple randomly assigned to TLS and conventional incubation (OR 1.0, 95% CI 0.13 to 7.49, 1 RCT, moderate quality evidence).All three studies reported clinical pregnancy rates (n = 994). There was no conclusive evidence of a difference in clinical pregnancy rate per couple randomly assigned to the TLS and conventional incubation arms (OR 1.23, 95% CI 0.96 to 1.59, 3 RCTs, n = 994, I(2) = 0%, low quality evidence). None of the included studies reported cumulative clinical pregnancy rates. AUTHORS' CONCLUSIONS: There is insufficient evidence of differences in live birth, miscarriage, stillbirth or clinical pregnancy to choose between TLS and conventional incubation. Further data explicitly comparing the incubation environment, the algorithm for embryo selection, or both, are required before recommendations for a change of routine practice can be justified.