What is a good embryo?

This article is professionally consulted by Master, Doctor Nguyen Thi Cam Van - IVF Lab Doctor - Reproductive Support Center - Vinmec Times City International Hospital.

There are many factors that influence the successful outcome of IVF infertility treatment, but embryo quality is considered the most important factor. About 60% of miscarriages are caused by abnormalities in the embryo. If you are having IVF treatment, transferring the best quality embryos will increase your chances of a successful pregnancy.

Prokaryotic stage (Day 0 - Day 1)
Sperm and egg fuse: At this stage, the nuclei from each gamete are next to each other forming a pronuclei that can be observed after 16- 18 hours insemination. This is how embryologists determine whether fertilization has occurred. Soon after, the two prokaryotes combine and form the embryo's chromosome set.
Divisional phase (Day 1 - Day 3)
Over the next few hours, the embryo will begin to divide from the first cell into 2 cells and after about 24 hours into 4 cells, 8 cells and so on. ..
Early morula stage (Day 3 - Day 5)
At about 3 to 4 days after fertilization, the embryo has 16 or more cells and the embryo is called a morula.
The blastocyst stage (Day 5+)
The cells begin to transform into the inner cell mass (ICM) and the trophectoderm (TE). These are parts of the embryo that will later become a fetus from the endoplasmic reticulum and the placenta from the ectoderm.

For each stage of embryo development, different criteria are used to evaluate the quality. These qualities can be correlated with the potential to develop into a healthy embryo later in life.
Evaluation of embryo quality is a non-invasive technique to select the best quality embryos for transfer into the uterus. In addition, embryologists look at whether the embryo's growth rate is too fast or too slow to predict the likelihood of an embryo's chromosomal abnormality.
Evaluation of embryo quality can be done at the division stage or blastocyst stage. If performed at the division stage, embryos will be evaluated for blastocyst count, homogeneity of blastomeres and the rate of cytoplasmic fragmentation in the embryo - this is an indication of fragments of cellular material. ruptured during cell division on day 3 post-fertilization, the embryo is considered good when it has 6-8 cells, the cells are uniform in size, and there is little or no cytoplasmic fragmentation. . Embryos with fewer than 6 cells, irregularly sized cells, and many cytoplasmic fragments are considered signs of poor embryo development and low implantability if transferred.

Gardner's system of grading embryos at the blastocyst stage was developed in 1999 and is the standard used by many IVF centers.
Vinmec IVF Center does not return embryo results to customers in the form of characters, but always explains how embryos are, good or bad.
On day 5 blastocysts were evaluated based on 3 criteria: embryo hatchability, ICM cell mass and TE cell mass. The blastocyst is considered good when the blastocyst cavity is enlarged or the embryo is extruding, the cells of the ICM block and the TE block are composed of many cells, the cells are tightly bound together.
In general, poor-quality division-stage embryos have few cells and are very fragmented. An embryo that develops very slowly or stops developing completely is not capable of developing into a fetus.
Good quality blastocysts are those that have dilated, may even begin to rupture, and are mostly stage 3 to 5. Embryos are graded AA quality (highest quality at both stages) occur uncommonly and commonly at levels B and C, but that does not mean embryo transfer will fail.

Vinmec IVF Reproductive Center is the address of infertility - infertility treatment chosen by many couples. So far, the Center has performed fertility support for over 1000 infertile couples with a success rate of 45%-50%. This rate is equivalent to developed countries such as the UK, USA, Australia,...
The center gathers a team of leading experts in the field of obstetrics and gynecology nationally and internationally, trained in centers leading in the world such as in the US, Singapore, Japan, Australia and famous fertility centers in the world.
With a high level of expertise and extensive experience, Vinmec IVF Center's experts are capable of synchronously and comprehensively deploying the most advanced assisted reproductive techniques today, helping realize the dream of becoming a parent of hundreds of families across Vietnam.