IVF Cycle - Infertility Solutions, Lehigh Valley, Pennsylvania

How an IVF cycle works

In vitro fertilization and embryo transfer or IVF, is a complex process containing many small steps. At Infertility Solutions, each couple meets with one of our nurses to individually review the details of that process and review an individual schedule to help you through the many details.

We work with patients in groups. We do this because it enables us to be more focused on the details we need to address. Most of those details relate to the IVF laboratory. The laboratory is one of the major determinants of success with IVF. We pick approximately one week each month in which to perform the laboratory part of IVF during. This enables us to fine tune the laboratory with quality control checks for the rest of the month. This limits our need to maintain, adjust, repair or clean any equipment while patient materials are using the laboratory.

For many of our patients, the first step is to synchronize their menstrual cycle with the lab. For most patients we do this initially by placing them on birth control pills. Birth control pills are not strictly necessary, but enable people to be on medications given by injections for the shortest period of time as well as provide some minor endocrine benefits for the cycle.

Patients then usually go on lupron to down-regulate their pituitary hormone production. This prevents their pituitary from producing hormones that could damage the eggs. Lupron is a minor modification of a 10 amino acid neurotransmitter naturally produced by the brain. Lupron belongs to a class of medications called GnRH agonists. There are more recently developed medications that have a similar effect and belong to the class of GnRH antagonists. We very rarely use them in part because of concern about possible side effects and because we can get the same results with medication with which there is more experience.

At this point the main medications start. We use a number of different combinations, but the key feature is that the main medications contain FSH, which is the hormone that causes follicles in the ovary to develop and mature. Patients are usually on this medication for 10 to 14 days. During that time we will be measuring estradiol and progesterone levels, evaluating the ovaries with ultrasound examinations, and adjusting the medications that are given.

When the ultrasound and hormonal parameters seem optimal for that patient, she will take HCG (in the form of Ovidrel). This will cause the eggs to mature (discarding half of their chromosomes in a polar body) and become free floating within the follicle. Enzymes begin to break down the follicle wall and will release the egg into the abdomen in about 37 hours. The egg aspiration procedure is scheduled for 36 hours after HCG is taken.

The eggs are taken out in our procedure room. A nurse anesthetist starts an IV through which he or she will give medications so that the patient does not feel the procedure. The follicles are visualized transvaginally by ultrasound. A needle is passed through the vagina into the follicle. The fluid in the follicle is aspirated and then passed to the embryologist. The embryologist then tries to find the microscopic egg in this follicular fluid. Great care is taken to maintain the egg in an environment that is stable and optimally meets its nutritional needs. Initially the primary concerns involve temperature, pH and air quality in the room and lab. This concern expands to include everything that come in contact with the egg/embryo including the gases around the embryo (see reduced oxygen tension), media constituents related to the embryo's state of development, and the stability of those environments.

The eggs are fertilized about 3 to 6 hours after they are obtained. This either involves inseminating the eggs with her partner's sperm, which has been specially prepared, or injecting a single sperm into each of the eggs (ICSI). If ICSI is done, the granulosa cells that layer the egg are enzymatically cleaned off so that the interior of the egg can be visualized and the egg handled more easily. If ICSI is not performed, the sperm will do much of this cleaning overnight. About five percent of patients with normal sperm will have no fertilizations with IVF. We often split the eggs on a first cycle and perform ICSI on some of them to decrease the likelihood of there being no fertilizations.

The eggs are examined for fertilization in the morning. The number of fertilizations as well as egg and embryo quality will be used to formulate a plan to transfer the embryos back to the patient after 2, 3, 5, or 6 days of incubation. Most of our patients have their embryos transferred on day 3. About one-third of patients have their transfer on day 5 or 6 (blastocyst).

The number of embryos to be transferred depends on their quality (cell number and normality of appearance), patient characteristics, and day of transfer. The number to be transferred is a joint decision balancing the wishes of the patient and the safety of the situation with respect to risk of multiple births.

On the day of transfer, assisted hatching is performed if indicated, embryos are incubated in embryo glue, and the transfer is performed using ultrasound guidance. The objective is to make the transfer be as gentle for the embryos as possible.

We use a number of different medical regimens to enhance and support implantation. These approaches have evolved over time based on medical publications. The regimens always include progesterone in some form.

Pregnancy tests are done in about two weeks. A positive pregnancy test is just the first step. Ultrasound is used to determine growth in the uterus, embryo number, and eventually embryo viability. If a heartbeat is seen as early as 6 weeks (3 weeks after the aspiration), there is about a 90% chance of a delivery.