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Assisted reproductive technologies, such as in vitro fertilization, IVF, have enabled thousands of otherwise infertile couples to have genetically related children. From its initial beginnings as the “stuff of science fiction”, IVF has evolved to a common, and often first line, treatment for infertility. IVF success rates have steadily improved to the  point where almost half of couples undergoing IVF will conceive. This percentage is higher or lower for individual couples based upon many factors including female age, cause(s) of infertility, previous treatments, the chosen clinics success rates, etc.
Clinics will usually provide a synopsis of their pregnancy success rates and data are submitted to the Centers for Disease Control (CDC) each year. However, the CDC data is usually “dated” by two years. Most highly successful programs also submitted their data to the Society of Assisted Reproductive Technology (SART) that is usually “dated” by one year.
"In vitro" literally translated means "fertilization outside of the body" which is where fertilization occurs in an IVF cycle. Eggs are retrieved from the ovarian follicles and combined with sperm in a Petri dish.
IVF consists of many stages and is performed by our highly trained team of professionals including fertility specialists, embryologists, nurses, and associated staff members. Our IVF team has extensive experience performing IVF and its associated procedures such as intracytoplasmic sperm injection (ICSI), assisted hatching, preimplantation genetic diagnosis (PGD), and others.
The first step of the IVF process is ovarian stimulation with injectable follicle stimulating hormone (FSH). FSH stimulates the ovaries to develop numerous follicles, each of which usually contains an egg. This process occurs naturally in each ovulatory cycle when the pituitary, under the influence of the hypothalamus, releases FSH to stimulate egg recruitment.
Ovulation induction is initiated using standard treatment protocols and dosages are adjusted based upon each patient’s individual response. Patients are carefully monitored using estradiol hormone levels, vaginal probe ultrasound, and physical examination. FSH should only be administered by a fertility specialist thoroughly trained, and experienced in its use to avoid potential serious side effects.
As healthy follicles mature they produce estrogen, and along with progesterone, these hormones cause the endometrium to thicken and become more vascular. This development is necessary to support a developing embryo.
Patients receive either a GnRH agonist such as leuprolide acetate (such as Lupron®) or a GnRH antagonist (such as Antagon® [Ganirelex acetate] or Cetrotide® [Cetrorelix acetate]) to control ovulation. These products can a block the production or release of hormones, such as FSH and LH. Ovulation cannot occur while a patient is receiving proper doses of one of these drugs. Otherwise, ovulation might occur before the eggs can be retrieved resulting in the “loss” of the ovarian stimulation cycle for IVF.
Once the eggs are mature, an injection of human chorionic gonadotropin (hCG) is administered and egg retrieval is scheduled. In a natural cycle, ovulation is stimulated by a surge of luteinizing hormone (LH). Ovulation is triggered with hCG in the same manner as LH. We discuss hCG and LH products in the fertility drugs section.
Egg retrieval is performed under light sedation using ultrasound guided transvaginal egg retrieval. A small “needle” is passed through the back of the vagina and into the follicle on the ovary. The egg is gently “suctioned” and retrieved in its follicular fluid. Once retrieved the “solution” is immediately passed to the embryologist who identifies and separates the eggs and places them in specially prepared media.
The remaining “follicular structure” is known as the corpus luteum. The corpus luteum produces progesterone to help complete endometrial development. After the embryo implants in the endometrium, the placenta also produces progesterone. IVF patients receive progesterone medication to offset the effects of the GnRH agonist or the GnRH antagonist.
The male usually provides sperm by masturbation and it is washed and specially prepared for exposure to the eggs. In cases where there is a male infertility component, procedures such as intracytoplasmic sperm injection (ICSI) are performed at this point. In ICSI, a single sperm is injected directly into the egg. If there are no sperm in the ejaculate, they can often be taken directly from the testicles or the reproductive tract. This is discussed in detail in the ICSI and male infertility sections.
After fertilization, the embryos are place in an incubator which tightly controls temperature, atmosphere, pH, and other environmental factors. The embryos remain in the incubator until mature, usually three to five days. Five day embryos have usually developed to the blastocyst stage, which is discussed on a separate Web page.
Once the embryos mature, the embryo transfer is scheduled. This is a painless procedure usually requiring less than ten minutes and is similar to IUI. The embryo is gently placed directly into the uterus. Patients are advised when to return for a pregnancy test (usually two weeks later).
“First line” indications for IVF may include tubal disease, advanced female age, ovarian failure where a donor’s eggs are used, severe male infertility when ICSI is needed, unexplained infertility, and others. When the tubes are blocked or damaged, IVF or surgery may be appropriate depending upon several variables. Since the eggs are retrieved directly from the ovaries, they do not have to pass through the fallopian tubes.
Older women may be candidates for IVF depending upon many variables including previous treatments, ovarian reserve, FSH levels, results of the Clomiphene Citrate Challenge test, and others. Many of these women are candidates for the donor egg program. Sometimes a woman may fail treatments such as several cycles of IUI for unexplained reasons. IVF allows the embryologist to observe and document fertilization.
If a man’s sperm count is very low or if poor fertilization is predicted based on a test such as Kruger strict morphology then fertilization with IVF using ICSI may be needed in order to conceive. Our physicians discuss all treatment options in detail with each couple.
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