Sunday, October 11, 2009

Fertility Treatment


Fertility Treatment
Infertility is a risk for all women who receive chemotherapy for breast cancer. Still, if your treatment plan includes chemotherapy, you can take steps that may allow you to have a baby even after your ovaries stop making eggs.
Extracting eggs
One option is to harvest mature eggs from your ovaries before you start breast cancer treatment. Without fertility drugs, only one or two eggs, at most, per cycle will be harvested. With fertility drugs, as many as eight to ten mature eggs can be obtained. But using fertility drugs greatly increases the amount of estrogen in the body that may stimulate the growth of breast cancer cells.
For this reason, doctors and researchers are now looking at using tamoxifen and aromatase inhibitors alone or together with traditional fertility drugs to both stimulate the ovaries and protect the body from high estrogen levels.
When tamoxifen or aromatase inhibitors are used in this way, they are given at high doses for just a few days. This is very different from how they're used in breast cancer treatment — at low doses, over a long period of time. These methods of fertility treatment are still experimental. But so far research has shown that they increase egg production without increasing the risk of breast cancer recurrence, at least in the first few years after treatment.
IVF
The eggs that are harvested can then be fertilized in a test tube with sperm from your partner, or a donor, depending on your situation. This is called in vitro fertilization (IVF). It's done in the laboratory, not within your body. The fertilized eggs grow briefly into tiny embryos and are then frozen.
After breast cancer treatment, if you're ready to get pregnant but your periods have not returned, the embryos are implanted in your uterus. Most clinics try not to transfer more than two at one time to avoid the risk of more than a twin pregnancy. Any number of embryos — or none might successfully implant and start to develop.
Freezing eggs
Single women without a specific partner may choose to freeze unfertilized, mature eggs. Pregnancy rates are low, however, once the eggs are thawed about 2% per egg. But techniques may improve in the next several years.
Freezing ovarian tissue
There are also experimental methods in which your ovary or ovaries are removed and parts of them containing unripe eggs are frozen. When you are ready to try to get pregnant after your cancer therapy is finished, the ovary tissue is put back in your body.
Strips of ovary tissue are thawed and transplanted either into your pelvis or your arm. The hope is that new blood vessels will grow, and the tissue will produce hormones and ripening eggs. Once the eggs are ready for ovulation, the goal is to remove and fertilize them, and then implant them in the uterus. So far, very few embryos have been produced in this way. And to date no baby has been conceived.
Donor eggs
If you decide not to extract and store your own eggs or ovaries, you can seek donor eggs. These can be fertilized with sperm from your partner or a donor and then implanted in your uterus.
Will fertility treatments work for you?
The success rate of fertility treatments varies from center to center. It also depends a great deal on your age. Younger women have a higher chance of pregnancy. The success rate drops significantly after age 40.
No matter what your age, the larger the number of eggs and embryos obtained, the higher your chance of getting pregnant in the future.
Before you go to a fertility center for treatment, find out what its pregnancy rates are. In the best programs, the pregnancy rates for women under 40 can be as high as 50%, while the rates for older women may be lower than 20%.
Fertility treatment using frozen embryos usually results in pregnancy rates that are about 33% lower than with fresh embryos. Most women who are about to start breast cancer treatment need to put their eggs or embryos away for later. This means freezing them.
If you're getting fertility treatment AFTER your breast cancer treatment is over and you're now ready to get pregnant, then eggs can be extracted and fresh embryos can be used.

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