What happens in the Fertility Lab?

In vitro fertilization, or IVF, is made up of four main components:

·       Ovarian stimulation

·       Egg retrieval

·       Embryo transfer

·       Embryo freezing.

Understanding each of these components is important, but between egg retrieval and embryo transfer lies a crucial step that patients cannot directly observe, the embryology lab.

Important decisions about your eggs and embryos are made in the lab. Not knowing what takes place there can make it seem like a black box.

After egg retrieval, the embryologist identifies the eggs from the surrounding follicular fluid and places them inside a labelled holding dish.

The embryologist then moves the eggs into individual wells within a drop dish and looks under a microscope to examine the maturity of the eggs.

There are three stages of egg maturity

-        germinal vesicle

-        metaphase I

-        metaphase II.

The eggs are then placed inside an incubator for four to six hours before fertilization. Fertilization can occur either by conventional fertilization or intracytoplasmic sperm injection (ICSI). In conventional fertilization, sperm are added to each well containing an egg with sperm provided from the intended parent or a sperm donor.

Now surrounded by numerous sperm, the eggs are placed back into the incubator in the hope that fertilization will occur. In intracytoplasmic sperm injection, only metaphase II eggs are injected. The embryologist injects one individual sperm inside each mature egg. The embryologist decides which sperm to insert into the egg based on the sperm's morphology.

Sperm come in a variety of shapes and sizes. Normally shaped sperm have a smooth, oval-shaped head and a uniform tail. Any abnormal-looking sperm are not chosen as they have lower fertilization potential. The eggs and sperm are placed back inside the incubator. The following morning, the eggs are checked for fertilization. Over the next five to six days, embryo development is periodically assessed.

Development of Embryos

·       On day one, the nuclei of the egg and sperm are visible. This is known as the pronuclei or zygote stage. The zygote divides into an early embryo with two cells.

·       The next day, the embryo divides into four to six cells.

·       On day three, the embryo divides into six to ten cells.

·       On day four, the embryo divides into a ball of cells called a morula.

·       On day five, a fluid-filled cavity develops within the morula and the entire mass of cells is now called a blastocyst.

The blastocyst consists of the trophectoderm that will form the placenta and an inner cell mass that will form the foetus. This is the usual rate of development, but some embryos take longer to reach the blastocyst stage. Not all embryos become blastocysts. About half of embryos will become blastocysts. Embryo transfer usually takes place on day five.

How are blastocysts selected for embryo transfer?

The lab uses the Gardner classification system. Blastocysts are given a number grade ranging from 1-6 based on how expanded the fluid-filled cavity is. This is an indication of its stage of development.

-        In grade one, the cavity takes up less than half the space of the blastocyst.

-        In grade two, the cavity takes up more than half the space. I

-        n grade three, the cavity has completely filled the blastocyst.

-        In grade four, the cavity has increased beyond the original volume of the embryo causing the zona pellucida, or the shell, to become very thin.

-        In grade five, the trophectoderm is hatching through the zona pellucida.

-        And in grade six, the blastocyst has completely hatched from the zona pellucida.

-        Next, the blastocyst is given two letter grades, one for the inner cell mass and one for the trophectoderm.

For the inner cell mass, grade A means there are many tightly packed cells, grade B, loosely packed cells, and grade C, very few cells.

For the trophectoderm, grade A means there are many cells, forming a cohesive layer, grade B means there are few cells, forming a loose layer, and grade C means there are very large cells, or unevenly distributed cells.

The embryologist considers the developmental stage and the grades of the inner cell mass and trophectoderm when selecting a blastocyst for transfer. All developing embryos, however, regardless of grade, have the potential to lead to pregnancy. Patients may elect to have pre-implantation genetic testing, or PGT, to determine if the embryo has the correct number of chromosomes. Using a laser, a sample of cells from the trophectoderm is removed and sent for analysis. This is known as embryo or trophectoderm biopsy. All the embryos that are biopsied are frozen, and the results are used to guide embryo selection for embryo transfer. The embryos are now ready to be transferred. Any blastocysts that are not transferred are frozen for future use. Each one is stored in separate straws. The straws are stored in a cane. The canes are then stored in a large canister, which is stored in a dewar filled with liquid nitrogen. Here, the embryos are kept frozen until they're thawed for future use. Understanding what happens in the fertility lab between egg retrieval and embryo transfer doesn't have to be a black box. It's important that you are completely informed at every stage of your fertility journey.

Now there are two major parts in IVF:

1.     Clinical part where ultrasonography is done, blood tests are done and we assess the development of the oocytes in the ovary.

2.     Embryology in IVF Lab

What happens in the IVF Lab in Dr. Kamini Rao Hospitals?

Let’s know how the embryo transfer happens in Dr. Kamini Rao Hospitals – the clinical wing of Medline Academics. On the day of egg retrieval, when we take out the oocytes from the patient, at the same time, the embryologists look for the presence of oocytes or eggs of the patient and after washing it is kept in the carbon dioxide incubator where they are cultured for 3 to 5 days. This is what generally happens in an IVF centre in Bangalore, but what make us different is the expertise. After collecting the eggs from the patient, we take the semen sample of the husband (the test for normal range is done before the procedure.) Then it is placed in the carbon dioxide incubator which has a body atmosphere also with a temperature of 37 degree centigrade. after 18 to 20 hours, we look for the presence of fertilization and after checking that we culture the embryos further for 3 to 5 days. The embryo transfer is generally done on day 3. If there are any extra embryos on day 3, then these embryos are either freezed or further cultured to form a blastocyst, and this blastocyst can also be freezed.

Role of an Embryologist

An embryologist's work is that once he works behind the scenes, he's responsible for creating and helping your embryos to grow inside the lab. They make the dream of infertile couples come true and we see the impact of success in the form of babies. An embryologist manages every aspect in the lab from the collection of the oocytes at the retrieval through the culturing from day five, six, and seven with the utmost attention to detail. So in the lab, we collect the oocytes on day zero. We fertilize them in the afternoon either by drop insemination of sperm or by ICSI, which is intracytoplasmic sperm injection, where we inject one sperm into each egg. We then culture those embryos after fertilization assessment on day one. We culture them through day five, six, and seven for either transfer, biopsy, and or vitrification. To do all this culture effectively, we do monitor every aspect in the lab from the temperature of all the equipment. Every item that comes in contact with eggs and embryos is quality controlled to ensure its safety. And we also monitor the culture system of the embryos very carefully. We monitor pH, temperature, and osmolarity to ensure the ideal developmental conditions for every embryo. Yes, embryologists are responsible for some of the most incredible parts of the IVF process. It's critical that these embryologists are experienced and operating under experienced leadership and supported with all of the state-of-the-art tools that are available today.

Oocyte vitrification has allowed a woman to preserve her fertility. Previously, in a diagnosis of cancer, a man could freeze his sperm. A woman could only freeze embryos, so if she was single, there really wasn't any option for her. Now that oocyte vitrification has become more reliable, it is a nice option for women to have to extend their fertility. Yes, vitrification has been a game changer as it's unlocked fertility preservation for any woman who might need it.

·       Start by collecting oocyte. This is an extremely crucial step.

·       Store these oocytes in separate media inside the lab. Ensure maintaining the temperature throughout the process of creating the embryos.

·       Regularly monitor the growth of the embryos

·       Poper communication between the fertility specialist

·       It's also very important that in a lab where they are doing procedures, should have adequate staff. So, a good number of staff is always very important, so that you cannot rush through the procedures. Less staff, create more problems, and there are the chances where the little mistakes can result, can be very awful, and it can be bad for the outcome or the results of a couple.

Besides all of these roles and responsibilities, the embryologist should also have quality education about the subject and the industry. As an embryologist, it's very important for you to be a very active part in research, to have proper embryology training in India, and knowledge about the latest technologies.

With a permanent work, it is often difficult to continue with additional qualifications and skills. But Medline Academics has a solution to this. Whether it an embryology training in India or a Fellowship in Embryology, the courses framed in this institution are accurate and up to date. Right from the basic modules to the advanced topics, the fellowship program covers everything that as an embryologist you are supposed to know. The practical training for the fellowship program will be covered at Dr. Kamini Rao Hospitals on site and under expert guidance. And what’s more? This program is university affiliated.

“If your cycle hasn't gone as well as you thought it would, whether it was poor embryo development, not enough oocytes, there's always changes that can be made in the future to improve your next cycle. So again, always remain hopeful.”- Pam Jarmuz, chief embryologist – Boston IVF (one of the largest and most acclaimed IVF labs in the world.)

Everybody wants a grade AA embryo and they feel that there's no hope if they don't have an AA embryo. An embryo graded as a BB, even though it just has a few less cells, has a very high potential. So there's no reason to lose hope if your embryo is not a BB grade.