The IVF Lab
The IVF laboratory at HRC Fertility — the place where the eggs, sperm and embryos are handled and IVF is performed — is an extremely important part of the IVF process. David E. Battaglia, Ph.D., HCLD, ELD, is the laboratory director and embryologist for HRC Fertility. The state-of the-art embryology laboratory was built in 1988 and is at the forefront of reproductive clinical research. In 1989, HRC Fertility performed one of the first preimplantation genetic diagnosis (PGD) cases in the United States for a sex linked genetic disorder.
After a patient's eggs are retrieved, the embryologist places them in an incubator and makes notes on their condition. The eggs and sperm are placed together in an incubator to allow fertilization, or a single sperm is injected, a procedure known as intracytoplasmic sperm injection (ICSI).
The day after retrieval is called Day 1, and the embryos are assessed. At this point the embryo is a single-cell zygote. On Day 2, the embryo typically divides into a four-cell embryo, and on Day 3 it typically becomes an eight-cell embryo. Embryos are assessed on Days 2 and 3 for transfer or placement into a blastocyst media until Day 5 or 6. Days 4-5, the embryo is a morula. Days 5-7, the embryos are blastocysts.
Generally embryos are transfered on Day 3 or Day 5. The embryologist assesses the embryos carefully to see which solution is better. Before the embryos are transferred, the embryologist evaluates them for their morphological appearance and grades them on a scale of one to four. The embryos that have the best characteristics and dividing normally are through to be more likely to successfully implant once the embryos are transfered to the uterus. Some of those good characteristics are:
- homogenous or light, non-grainy cytoplasm (gel-like substance residing between the cell membrane)
- smooth membranes
- cells that are approximately the same size
- cells that touch each other and form a round ball within the zona pellucida (the layer of proteins that contains the embryo)
- a zona pellucida that is clear and not too thick
- little fragmentation (individual cells within the embryo that have broken up and appear as fragments
It is important to note, however, that even embryos that do not have the greatest appearance can still result in a successful pregnancy and a healthy baby.