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In vitro fertilization and embryo transfer involves the harvesting of several oocytes (eggs) from the stimulated ovaries. This process allows the direct fertilization of the oocytes with sperm. The pre-embryo(s) thus formed can then be transferred into the womb at the right time. In the past, natural (unstimulated) IVF was practiced, but this was abandoned due to very low success rates. The current standard of care is to stimulate the female partner with injectable medications called gonadotropins in order to induce the maturation of several oocytes. This increases the odds of success and sometimes allows for the freezing (cryopreservation in liquid Nitrogen) of remaining pre-embryos which are not used "fresh." This gives patients a second chance at conception later when the frozen pre-embryos can be thawed and transferred into the womb at the right time.
After the oocytes are incubated for a brief period of time, they are fertilized with the partner's sperm. This occurs in the IVF and Embryo Culture Laboratory within the office. The following day, patients are contacted and informed of the status of fertilization. At that time an appointment is made for the embryo transfer. One of the key decisions is to decide how many embryos to transfer in order to increase the chance of success, but not put the patient at great risk of a multiple pregnancy. This is an individual decision which is based on the patient's age, embryo appearance, and ethical issues.
The process of "in vitro" fertilization involves several steps as follows:
1. Consultation with the doctor. During the initial consultation with Dr. Pabon, he will review all your pertinent medical history and usually perform a physical exam. This time is spent reviewing the indication for "in vitro" fertilization, the pre-cycle tests, the IVF procedures, and cost. If you have provided all pertinent records, Dr. Pabon will prescribe the medications and doses needed for the IVF cycle.
2. Consultation with the nurse or medical assistant. This time is very important because the prescribed stimulation medications are reviewed and the patient is provided with detailed notes on their particular type of stimulation protocol. It is important that both partners attend this meeting so that they can both receive instructions on the injection procedures. This consultation is best done early in the menstrual cycle before the planned IVF cycle.
These are pre-pregnancy tests which include a hepatitis screen, and an HIV screen on both partners. There are other pertinent tests which are ordered such as a rubella titer (to determine immunity to rubella). An FSH (follicle stimulating hormone) level is needed for all patients older than 35 years of age. The FSH levels must be drawn on cycle day two or three (cycle day one is the first day of menstrual flow).
The male partner must have a semen analysis performed within one year of the planned IVF cycle. A repeat test may be required if there has been a severe illness or other pertinent event since the last semen analysis. The only semen analysis tests that Dr. Pabon trusts are those done in an accredited fertility center.
5. Pre-cycle mock embryo transfer. The mock or "practice" embryo transfer is a special examination during which Dr. Pabon passes a soft plastic catheter through the cervix and into the womb in order to make a detailed map of the course of the cervix and the depth of the womb. This is done so that the actual transfer of the embryos can go smoothly. Many patients describe the procedure as feeling like a routine "pap" smear or exam. It is best if the initial attempt at the mock embryo transfer is done with a moderately full bladder. The bladder is usually full enough when the patient senses that she could void, but can defer voiding without discomfort.
6. Pre-cycle assessment of a normal uterus It is imperative that the patient that is about to enter an IVF cycle have a thorough evaluation of the womb. This is required in order to assure that the womb does not have any kind of abnormality that could get in the way of an early pregnancy. Evaluation of the womb can be done with various methods. The easiest and least expensive way to evaluate the womb is with the hysterosonogram or saline infusion ultrasound. This office procedure requires the placement of a small soft rubber catheter into the cervix (the opening to the womb) and the slow infusion of sterile saline into the womb. The saline enhances the passage of ultrasound waves and allows a very detailed evaluation of the entire womb. Some patients may have special situations which may require the use of a standard X-ray (the hysterosalpingogram) or a hysteroscopy (a direct visual inspection of the inside of the womb using a small viewing telescope).
The majority of IVF cycles begin with two blood tests. These are a pregnancy test and a progesterone level. These blood tests are drawn on cycle day 19, 20, 21, or 22. If the pregnancy test is negative and the progesterone level indicates ovulation, then the down regulation phase begins. Down regulation refers to the suppression of the pituitary gland secretion of hormones that normally stimulate the ovary. The pituitary gland is located at the base of the brain and is responsible for control of the secretion of hormones. Lupron is a hormone that is similar to the natural hormone that the hypothalamic portion of brain uses to communicate with the pituitary gland. When Lupron is used daily, the pituitary gland initially releases ovarian stimulatory hormones, but soon becomes "tired" and stops secreting reproductive stimulatory hormones. The pituitary is thus "down regulated." The down regulation of the pituitary allows for a more controlled ovarian superstimulation with the injectable stimulatory drugs. Lupron is used for down regulation and is usually begun on cycle day 21 or 22 and continued for the remainder of the cycle until instructed otherwise. Note that the dose of Lupron is changed when the stimulatory drugs are begun. Not all IVF protocols use a down regulation phase. Please remember to call the office for an initial or "baseline" ultrasound when you have used Lupron for 10 days or when menstruation begins (whichever comes first).
8. The ovarian stimulation phase The Gonadotropins are the stimulatory hormones. You may know them by their Brand names such as Pergonal, Metrodin, Humegon, Fertinex, Follistim, Repronex, Gonal F, and Profasi. These preparations contain Follicle stimulating hormone (FSH), Luteinizing Hormone (LH), or Human Chorionic Gonadotropin (hCG or profasi). The different brands contain differing amounts of FSH and LH. Some brands contain almost all or all FSH. The profasi contains hCG. This hormone is the one that is used at the end of the stimulation in order to induce final maturation of the oocytes (the eggs). The stimulation phase is usually begun soon after the baseline or initial ultrasound. These injectable medications act directly on the ovaries in order to stimulate the development of several oocytes. During the stimulation phase, several ultrasounds and estrogen levels will be performed in order to gauge your individual response. Near the end of the stimulation phase (average length is usually 8-10 days) you may require daily tests in order to determine the perfect time for the final injection (hCG).
The egg retrieval is scheduled approximately 34-36 hours after the hCG injection. The egg retrieval requires intravenous sedation and is done in the office procedure room. The eggs are suctioned into a test tube by a needle that is guided by vaginal ultrasound. The needle is inserted through the top of the vagina by the use of a needle guide attached to the ultrasound vaginal probe. This sounds awful, but due to the anesthetic, the procedure is not painful. On the contrary, patients usually only feel mild to moderate menstrual-like discomfort after the procedure. After the oocytes are in the incubator, they will be inseminated individually. The retrieval is an outpatient procedure. Remember that your ovaries are swollen and that you should take it easy as instructed in the post-procedure instructions. You will be contacted the next day in order to inform you of the number of eggs that have been successfully fertilized.
10. The pre-embryo transfer consultation There should have been a dialogue about the possibility of a multiple pregnancy (twins, triplets, quadruplets, quintuplets, etc.). Unfortunately, in order to increase the chance of a successful IVF cycle -- that is, a pregnancy that results in at least one baby -- the usual number of embryos transferred varies from at least two in a very young patient to sometimes four or more in older patients or in those with multiple failed cycles. Unfortunately, the final decision as to how many embryos are transferred cannot be made until the moments just prior to the embryo transfer. This is because the appearance or quality of the available embryos is a factor that is considered. This pre-embryo transfer consultation occurs in the procedure room immediately after the embryos are viewed and prior to "loading" them into the embryo transfer catheter.
The embryo transfer is a very important procedure. After you and Dr. Pabon have determined the number of embryos to be transferred as reviewed above in item no. 10, the embryos will be "loaded" into the special embryo transfer catheter and gently passed through the cervix and into the womb. You will be asked to rest for 20 to 30 minutes after the transfer. It is important to remember that the transfer of embryos usually requires the bladder to be moderately full as described in item no. 5.
12. The post embryo transfer phase The progesterone supplementation begins the evening of the egg retrieval. During the 14 days following the embryo transfer, you will continue the progesterone supplementation and watch for signs of ovarian hyperstimulation. Ovarian hyperstimulation refers to a severe ovarian enlargement that can cause low abdominal pain, nausea, bloating, temporary fluid weight gain, and vomiting. This occurs to very few patients. You must remember to keep well hydrated by drinking 8 glasses of water per day and to contact Dr. Pabon if you experience any of these symptoms. You must be aware that ovarian hyperstimulation can be deadly if you allow yourself to become very ill and dehydrated. This is because in the very rare severe cases, the blood can become concentrated with increased coagulability that can lead to blood clots which can dislodge and occlude the blood supply to vital organs such as the lung (pulmonary embolus) or brain (stroke). Understand that severe ovarian hyperstimulation with catastrophic consequences is an extremely rare event.
13. The initial pregnancy test You have gone through much during the "in vitro" fertilization and embryo transfer cycle. Unfortunately, the day of the pregnancy test is usually the most difficult. It is filled with much anxiety and can conclude with extreme emotion. This can be bliss or deep sadness. A negative pregnancy test can lead to an understandable temporary "reactive" depression. It is important to use your support system (husband or close family and friends) during this difficult day. If your result is positive then you must make an effort to control your excitement. The best advice is to smile and not get "too high." The reason for this is that despite an initial positive pregnancy test, the possibility of a miscarriage still exits. The initial pregnancy test will be repeated in 48 hours. Additional tests will be ordered on an individual basis.
14. The post "in vitro" consultation This consultation is a meeting with Dr. Pabon that is scheduled if your cycle was unsuccessful. This will involve a complete review of your cycle and will conclude with a discussion of options based on insights gained from your cycle.
15. The referral to the obstetrician/gynecologist The great majority of patients are referred by OB/GYN physicians or nurse practitioners. Once it has been determined that your pregnancy is progressing without any complications, you will be referred back to your Obstetrician or Nurse Practitioner for the management of the remainder of your pregnancy and the delivery of the baby or babies.
After you are dismissed from our care, you are encouraged to call our office so that we know how you are doing. Baby pictures and nice notes are treasured. As you may have gathered, the care that we provide is very personal. The one-on-one attention that you will receive here is extremely rare. Infertility is stressful enough. We try to make the evaluation and treatment as tolerable as possible, always trying to be sensitive to your feelings and expectations. Contact us for more information on In Vitro Fertilization (IVF)
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