The IVF Lab

In vitro fertilization (IVF) is a laboratory procedure from the time eggs are retrieved from a woman until the time the embryo is transferred back into the uterus — a time period of anywhere from three to five or six days. The laboratory quality and procedures during this time are crucial to the success of IVF. A fertility clinic lab is typically run by an embryologist, which is a scientist who is involved in fertility treatment and reproductive research. Embryologists collect eggs, assess and prepare sperm samples from partners, and inject eggs with sperm.

Every fertility clinic has an in vitro fertilization (IVF) lab, which is the place where eggs, sperm and embryos are handled, and IVF is performed. The lab environment can define whether the embryo will be viable or not, depending on such variables as:

• the experience and training of the embryologist
• the equipment in the lab
• the lab protocols
• the culture media for the embryos
• the lab's quality control for such things as air quality
• how vigilant the lab is in ensuring embryos are not compromised

The embryos are handled in the lab for several days. After egg retrieval, the embryologist places eggs in an incubator and makes notes on their condition. Then, the eggs and sperm are placed together in an incubator to allow fertilization. Or, a procedure known as intracytoplasmic sperm injection (ICSI) is performed in which a single sperm is injected into the egg.

The day after retrieval is called Day 1, and the embryos, which at this point are single-celled zygotes, are assessed. 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.

Embryos are typically transferred on Day 3 or Day 5. The embryologist assesses the embryos carefully to see which day it would be better to transfer. 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 are dividing normally are thought to be more likely to successfully implant.

Talk to your fertility doctor about the fertility clinic's IVF lab and ask questions about quality control and the experience of the embryologists who will be handling your embryos.