What is COS IVF?

During a natural menstrual cycle, a woman’s ovaries release one egg (two, at most) every 28-35 days, meaning that there is only one egg that can be fertilized during each cycle. If a woman is having trouble getting or staying pregnant, she may choose to undergo in vitro fertilization (IVF).

During IVF, our fertility specialist Dr. Brandeis will prescribe special fertility drugs that contain the follicle-stimulating hormone (FSH), which makes it possible for more follicles to grow during a woman’s cycle. This ensures that we are able to collect more mature eggs for fertilization and implantation. By being able to produce and fertilize more eggs in just one cycle, we increase the odds of a woman getting pregnant. This is also known as controlled ovarian stimulation or COS IVF.

During COS IVF, we are not creating eggs but simply being able to save more of the eggs that the body would otherwise not use during a typical menstrual cycle to improve your chances of pregnancy. We can often determine how many eggs we will be able to collect through a simple ultrasound performed during your consultation. The number of eggs that can be retrieved will vary month by month and with a woman’s age.

Controlled ovarian stimulation is customized to each patient, and there are certain factors that we will need to take into account, such as ovarian reserve test results, age and medical history. From there, we will determine the right medication that the patient will need to administer, typically as an injection, every day for anywhere from eight to 14 days.

Once the woman has finished injecting the medications used to stimulate the follicles to produce more eggs, another shot (known as the trigger shot) will be administered to induce ovulation within a 36-hour window. At that point, your doctor will have already scheduled your office visit to make sure that the eggs are retrieved during ovulation.

There are different methods and protocols used for COS IVF, and Dr. Brandeis is happy to discuss the different approaches with you to help you decide which one will best suit your needs.

Do you have questions about COS IVF? Want to find out if IVF is the best way to increase your odds of getting pregnant? If so, call Brandeis Fertility Center of New York at (718) 433-3833 to schedule a consultation.

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