The IVF Procedure: Egg Retrieval
For couples who are having difficulty conceiving, one option that your doctor may present to you is in vitro fertilization (IVF). But before you make any decisions, it’s a good idea to find what the procedure itself involves. One of the most important stages of IVF is the egg retrieval process. Here are some of the basics of the egg retrieval process involved in IVF treatment.
What is Egg Retrieval?
During egg retrieval, viable embryos are retrieved from a woman’s ovaries. They will later be mixed with the man’s sperm in preparation for fertilization. However, before egg retrieval can occur, a woman must already be producing sufficient follicle production, which is stimulated by certain hormones. Egg follicles are fluid-filled sacs located inside the ovaries.
When a woman is born, she already has millions of these eggs follicles, each of which contains an immature egg. Once she reaches puberty she has around 400,000 of these eggs. During each menstrual cycle multiple follicles begin to develop due to follicle-stimulating hormone (FSH), a hormone secreted by the pituitary gland. Each month during the menstrual cycle, thanks to certain hormones, multiple follicles begin to develop. The strongest follicle will attract most of the FSH, causing it to break open and release an egg while the remaining follicles die off. This is ovulation.
Once a number of follicles are produced, fertility specialists can then remove them from the ovaries in order to attempt fertilization. If fertilization is successful, the embryos will be placed back in to the woman's uterus.
Stimulating Egg Development
To make your chances of fertilization greatest, you will need as many eggs as possible retrieved. However, because most infertile women have difficulty producing sufficient follicles on their own, the fertility specialist will usually prescribe medications to help stimulate follicle development (this is also referred to as ovulation induction). These medications may include:
These medications are generally given for a period of ten days or so.
Monitoring Egg Development
Because timing is so important in the egg retrieval process, your ovaries will be monitored for follicular development. This is done to avoid letting the follicles develop too much, since the egg inside will become too mature for efficient fertilization. This is typically done through an ultrasound. When your follicles reach just the right maturity, egg retrieval can begin.
Retrieving the Eggs
The retrieval process is relatively simple. The first step is follicular aspiration – a process in which a hollow needle is inserted through the top of the vagina and into the ovaries so that follicles from both of your ovaries can be removed. This needle is then used to suction out any follicles that may be present in the ovaries.
In order to ensure the needle reaches the appropriate area of the ovary, you will be given an ultrasound. This will allow your health care provider to insert the needle into your ovary at just the right place. Once the follicles have been removed, they will be examined under a microscope to ensure the presence of a viable egg, and will then be placed in an incubator.
Normally the number of eggs removed range between five and 20, depending on your age and the effect of your fertility medications. The process itself is short, usually only lasting between 15 and 30 minutes.
After the egg retrieval, all viable eggs will be mixed with a sperm sample provided by your partner or sperm donor. These eggs will then be cultured overnight until they can be checked for fertilization. If fertilization occurs, you’ll move to the next stage of IVF treatment: embryo transfer.