Good For

What is Biology Good For?
Helping A New Life Begin: In Vitro Fertilization

(This assignment is optional and is due on Friday, February 28, 2003 by noon. Read this essay and answer the questions at the bottom for 3 extra credit points. It is not necessary to visit the links in the text unless you are interested in more information.)

Good For 1, Good For 2, Good For 3, Good For 4, Good For 5,

In vitro fertilization (IVF) is a fertility procedure first succeeded in 1978 by the late British gynecologist Dr. Patrick Steptoe and his co-researcher, embryologist Robert Edwards. Since then, the procedure has been further developed and fertilization outside the human body is now available throughout the Western world. In fact, more than 300 centers in North America alone practice IVF and over 40,000 babies worldwide have been born after IVF. [Image]

What is in IVF?

Simply stated, IVF involves removing eggs from a woman, fertilizing them in the laboratory culture dish (the name "test-tube baby" is actually a misnomer) and then transferring the fertilized eggs - now called "zygotes" - into the uterus a few days later.

Ultrasound of Follicles

Egg with two pronuclei

Eight cell Pre-embryo

Preparation for IVF:

Hormones injections of Lupron, Metrodin, Pergonal or Humegon allow the ovaries to develop many follicles, inducing the woman to 'super ovulate', and increasing the number of egg-containing follicles released.
Several follicles are stimulated to develop at the same time so that a group of eggs will be available for fertilization.
Tests and ultrasounds regulate the woman's cycle to determine the optimal time for follicle / egg retrieval.

Egg Retrieval

Using an ultrasound-guided needle placed through the vagina, the doctor retrieves follicular fluid / eggs from the follicles.
This procedure requires neither hospitalization nor general anesthesia. (Local anesthesia and/or mild analgesics may be taken to alleviate any discomfort.)
The eggs are immediately identified by an embryologist, and then placed in an incubator.
After a short rest, the women returns home and can resume normal activity.

Egg Fertilization:

When ready for fertilization, about 50,000 to 100,000 of the most motile sperm are incubated with each of the woman's eggs.
Or, to increase the rate of fertilization, a fertility doctor may perform Inter Cytoplasmic Sperm Injection (ICSI), which is direct insemination of a single sperm into the egg. [Image and movie]
If more than four eggs are retrieved, all eggs are fertilized and the extra embryos may be frozen for future use. If freezing is not available or desired, the eggs may be donated to another infertile couple or to the IVF center, which would then use them for refining culture methods and techniques.

The four basic steps to fertilization:

1. Egg's metabolism must be turned on.

2. One sperm must penetrate the egg.

3. A barrier, which keeps other sperm out, must be erected.

4. Nuclei and chromosomes form the egg and sperm must unite.

Embryo Transfer:

Once the fertilized eggs have divided and have therefore become "pre-embryos," they are ready for implantation into the woman's uterus.
Transfer usually takes place 30-60 hours post-fertilization, between the two- and eight-cell stages.
The fertilized eggs are transferred through the vagina and into the uterus via a thin plastic catheter.
Usually two to four eggs are transferred during each IVF cycle. (Although the rate of pregnancy is increased, so is the likelihood of a multiple pregnancy.)
This is an outpatient procedure and requires no anesthesia.
After resting for a few hours, the woman returns home and can resume normal activities within a day or two.

This "What is Biology Good For" was researched and written by IUPUI student Jennifer Manske, as part of an undergraduate research project.

References
IVF In Vitro Fertilization.
IVF.com In Vitro Fertilization.
IVF.com Photo Gallery.
In Vitro Fertilization.

The text of this "What is Biology Good For" exercise is copyrighted under the name of Dr. Kathleen A. Marrs, 1999, 2000, 2001, 2003. There are no restrictions on its use by educators or by non-profit institutions as long as its content not modified, proper copyright acknowledgement is retained, and this statement is not removed.

Please type the last 4 digits of your Student ID Number: (Important!)
Please type your LAST name, and FIRST initial or first name:

Extra Credit Questions:
1. What happens to any surplus (extra) pre-embryos after IVF? List 1 possibility. (See p 4 in the link)
2. What is the average cost (per mentrual cycle) for an IVF? (scroll down to find out!)
3. What is the average success rate for IVF?

Please answer all three questions here:

You may change your mind as often as you wish. When you are satisfied with your responses click the SUBMIT button. You will receive a "THANK YOU" page as a confirmation that your response has been sent to me.

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