Welcome Egg Donors!
In order for you to understand the process more clearly, here is a step-by-step guide of what’s ahead.
In Vitro Fertilization
In vitro fertilization or IVF is the process of the extraction of eggs from the ovaries, fertilization in the laboratory with sperm and subsequently the transfer of one or two embryos into the uterus.
In most cases, the treatment cycle starts by placing the donor and intended mother on birth control pills (BCP). This is for scheduling purposes. By putting them on BCPs, we are able to manipulate their menstrual cycles and synchronize them. This allows us to also plan ahead and provide all parties with specific treatment dates that can be set well in advance. The donor and intended mother will usually take these pills for a period of 3-6 weeks. BCPs will in no way harm the chances of conceiving, in fact, it might help produce a synchronously growing batch of follicles or eggs.
Fertility hormones are typically started on the second day of the donor’s period and after a baseline blood measurement or ultrasound examination to check for the presence of cysts. Medications are sent to the donor in advance. Different types of hormones such as Gonal-f®, Follistim® or Bravelle® (given subcutaneously (SQ), Repronex® (Intramuscular (IM or SQ)) or Menopur® (SQ) are used to stimulate the ovaries. These medications produce multiple eggs. The response to these drugs varies according to the patient’s age, her ovarian reserve, and the amount of drugs given. The dose should be clearly indicated on the calendar. Ideally, a donor will produce 15-30 eggs. These drugs are given once (usually in the evening) or twice daily (morning and evening). Mixing and injection instructions will be given to the donor prior to treatment initiation. These hormones are usually taken for 9 to 14 days. Some patients might need a longer period of time to have a successful stimulation. A vaginal ultrasound will be performed one week after the start of these medications. The purpose of this examination is to see the ovaries and count the number of follicles present. A follicle is the fluid-filled sac that contains the egg. Each follicle usually contains one egg.
By counting the number of follicles the clinic can determine how well the donor has responded to the fertility drugs. They will also measure the follicles. The size of the follicle gives a good idea about the maturity of the egg. As the donor continues to take the fertility drugs, these follicles will grow (about 3 mm in 2 days); and at a certain point in time they will be ready to be harvested. The clinic will want to retrieve the eggs when the majority of the follicles are around 18 mm in size.
Occasionally a blood test for the hormone Estradiol (E2) level is also checked. As the follicles (containing the eggs) mature, the eggs secrete the Estradiol hormone, therefore measuring the level of this hormone in the blood often gives a good idea as to how the ovaries are responding to the drugs. The level increases over the next several days as the eggs are maturing and the follicles are growing. The more eggs or follicles a donor has the higher the Estradiol level.
When the physician decides that the follicles are ready to be aspirated (to remove the eggs), the patient will be given instructions to take an HCG injection 36 hours prior to the Egg Retrieval. This medication is crucial. It will “push” the eggs through their final stages of maturation and will release them from their attachments to the walls of the follicles to float inside the follicular fluid. If HCG is not taken correctly and at the exact time specified, the eggs will not be mature and will not be able to be aspirated.
The donor will be given written instructions on how and when to administer this medication.
The HCG injection is usually given at night (usually between 7 PM and 11 PM); the Egg Retrieval is scheduled 36 hours after the injection, which falls two days later in the morning between 7 AM and 11 AM.
Oocyte or Egg retrieval
When the size of the leading follicles reaches 18 to 20 mm in average diameter and the estradiol hormone level is appropriately elevated, then it is time for the eggs to be “harvested”. The egg retrieval will be scheduled 36 hours after the HCG injection. For instance, if the HCG is given on a Monday at 8:45 PM, then the egg retrieval will be performed on Wednesday at 8:45 AM.
The donor needs to be at fertility clinic at least 1 hour prior to the scheduled time of Egg Retrieval (ER). The donor should not eat or drink anything after midnight, the night before the ER day.
The ER is performed under “general anesthesia” but without intubation. The patient will not feel any discomfort during the procedure and will wake up within 10 to 15 minutes after the ER. Depending on the number of follicles present, the ER will usually last 10 to 30 minutes.
The procedure is performed under ultrasound guidance similar to the vaginal ultrasound examination that the patient has during follicular monitoring. A needle guide is attached to the ultrasound probe, a long needle is introduced through the guide, and under direct visualization each follicle is punctured and the fluid (along with the egg floating in it) is aspirated. The fluid is then immediately sent to the laboratory where the embryologists search for the eggs, isolates them and places them in incubators. At the completion of the ER, the donor is taken to the recovery area where she will stay for about an hour. Pain medications might be administered at this time as needed. Occasionally, some nausea might also occur which usually dissipates within a few hours.
After about an hour when the patient is fully awake and relatively pain-free, instructions are given by the recovery nurse and the patient is discharged home. The donor must be accompanied by someone who can drive her home or to the hotel and should not be left alone for the rest of the day.
Once the eggs are harvested and cleaned in the laboratory, they are either incubated with sperm overnight or sperm is directly injected into each egg to fertilize it (ICSI).
Roughly 16 hours after insemination (usually the next day), the embryologist will check on the status of the fertilized eggs.
A fertilized egg is called an embryo. An embryo goes through stages of development until it is ready for transfer to the uterus.
It is preferred, to transfer embryos that have reached the stage called Blastocyst, which is 5 days after the egg retrieval.