即時觀測胚胎Time-lapse, 新一代評估胚胎morphokinetics 新方法

即時觀測胚胎Time-lapse,  新一代評估胚胎morphokinetics 新方法
可精確觀測胚胎之分裂速度正確與否(time of division to 5 cells, t5; time between division to 3 cells and subsequent division to 4 cells; duration of cell cycle two, i.e. time between division to 2 cells and division to 3 cells, cc2 (≤11.9 h)),
以挑選最好胚胎並評估培養環境與培養液是否理想

http://humrep.oxfordjournals.org/content/26/10/2658.full

The use of morphokinetics as a predictor of embryo implantation^†

1. Marcos Meseguer1,*, 
2. Javier Herrero1, 
3. Alberto Tejera1,
4. Karen Marie Hilligsøe2, 
5. Niels Birger Ramsing2 and 
6. Jose Remohí1

+Author Affiliations

1. ¹Instituto Valenciano de Infertilidad, Universidad de Valencia, Plaza de la Policía Local, 3, Valencia 46015, Spain
2. ²Unisense FertiliTech A/S, Aarhus, Denmark

1. ↵*Correspondence address. Tel: +34-96-305-0988; Fax: +34-96-305-0999; E-mail: marcos.meseguer@ivi.es

• Received March 25, 2011.
• Revision received June 27, 2011.
• Accepted July 4, 2011.

 

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Abstract

BACKGROUND Time-lapse observation presents an opportunity for optimizing embryo selection based on morphological grading as well as providing novel kinetic parameters, which may further improve accurate selection of viable embryos. The objective of this retrospective study was to identify the morphokinetic parameters specific to embryos that were capable of implanting. In order to compare a large number of embryos, with minimal variation in culture conditions, we have used an automatic embryo monitoring system.

METHODS Using a tri-gas IVF incubator with a built-in camera designed to automatically acquire images at defined time points, we have simultaneously monitored up to 72 individual embryos without removing the embryos from the controlled environment. Images were acquired every 15 min in five different focal planes for at least 64 h for each embryo. We have monitored the development of transferred embryos from 285 couples undergoing their first ICSI cycle. The total number of transferred embryos was 522, of which 247 either failed to implant or fully implanted, with full implantation meaning that all transferred embryos in a treatment implanted.

RESULTS A detailed retrospective analysis of cleavage times, blastomere size and multinucleation was made for the 247 transferred embryos with either failed or full implantation. We found that several parameters were significantly correlated with subsequent implantation (e.g. time of first and subsequent cleavages as well as the time between cleavages). The most predictive parameters were: (i) time of division to 5 cells, t5 (48.8–56.6 h after ICSI); (ii) time between division to 3 cells and subsequent division to 4 cells, s2 (≤0.76 h) and (iii) duration of cell cycle two, i.e. time between division to 2 cells and division to 3 cells, cc2 (≤11.9 h). We also observed aberrant behavior such as multinucleation at the 4 cell stage, uneven blastomere size at the 2 cell stage and abrupt cell division to three or more cells, which appeared to largely preclude implantation.

CONCLUSIONS The image acquisition and time-lapse analysis system makes it possible to determine exact timing of embryo cleavages in a clinical setting. We propose a multivariable model based on our findings to classify embryos according to their probability of implantation. The efficacy of this classification will be evaluated in a prospective randomized study that ultimately will determine if implantation rates can be improved by time-lapse analysis.

Figure 2

Percentage of embryos having completed a cell division by a given time after insemination. Blue curves represent implanting embryos; red curves represent embryos that did not implant. Four curves of each color represent completion of the four consecutive cell divisions from 1 to 5 cells i.e. t2, t3, t4 and t5.

Table I

Exact timing of embryo events analysed from transferred implanted and not implanted embryos.

Parameter	Implanted embryos				Not implanted embryos				Homogeneity of variances
	Mean (h)	SD (h)	n	Normal dist.	Mean (h)	SD (h)	n	Normal dist.	P-value
t2	25.6	2.2	61	Yes	26.7	3.8	186	No	0.022
t3	37.4	2.8	61	Yes	38.4	5.2	185	No	0.002
t4	38.2	3.0	61	Yes	40.0	5.4	182	No	0.004
t5	52.3	4.2	61	Yes	52.6	6.8	167	Yes	<0.001
cc2	11.8	1.2	61	Yes	11.8	3.3	185	No	0.006
s2	0.78	0.73	61	No	1.77	2.83	182	No	0.016