Practical implications
The extension of this technique to the safe assessment of human embryos in vivo while they are in culture is logical and opens up an entire area of both investigation and potential clinical practice. If the metabolic activity of the individual embryos indicates the likelihood of implantation and development, then this could become a new standard in the assessment of every embryo resulting from an ART cycle.
Much work will be required to translate this exciting new technique to human embryos, but it does offer a logical approach to the longstanding problem of embryo assessment.
Real-time assessment
Schuster TG, Cho B, Keller LM, Takayama S, Smith GD. Isolation of motile spermatozoa from semen samples using microfluidics. Reproductive Biomedicine Online. 2004;1(Jul-Aug):75–81.
One of the challenges of assessing individual human embryos in vivo is the dilution effect on any secretion products secreted from an embryo into the relatively vast amount of media in a traditional ART Petri dish. This report describes the first of a series of microfluidic devices designed to separate motile from nonmotile spermatozoa in very small volumes. Such devices can be used to isolate motile sperm from nonmotile sperm and debris for ART procedures when numbers are exceptionally low.
However, similar microfluidic devices are being developed to include tiny chambers that could be used to contain individual human embryos receiving a constant stream of nutrient media with a constant output of spent media and secretory products. In conjunction with the capacity to analyze such tiny amounts of secretory products in vivo from individual cells, this suggests a system for evaluating all human embryos in modern microchambers and continually monitoring for appropriate secretion and subsequent selection for optimal reproductive capacity.
Practical implications
The promise of real-time embryo assessment is certainly upon us, though much work needs to be done to develop these microfluidic incubation chambers before they will be clinically applicable.
For the practicing Ob/Gyn, it is useful to know that the era of preimplantation evaluation of all embryos is not far off. Whether that will translate into fewer fetal/neonatal defects remains to be seen.
The author reports no financial relationships relevant to this article.