In vitro fertilization with coculture
Endometrial Coculture is a technique of assisted reproductive technology. It involves placing a patient's fertilized eggs on top of a layer of cells from her own uterine lining, creating a more natural environment for embryo development and maximizing the chance for an in vitro fertilization (IVF) pregnancy.
Coculture can be an effective treatment for patients who have failed previous IVF cycles or who have poor embryo quality.
A typical Coculture cycle consists of the following steps:
1. Once a patient has been deemed an appropriate candidate for the procedure, she undergoes an endometrial biopsy during which a small piece of her uterine lining is removed.
2. The uterine lining sample is sent to a research lab, where it is treated, purified and frozen.
3. The patient then undergoes a typical IVF cycle and is given medication to stimulate egg growth in her ovaries.
4. The patient's eggs are retrieved and mixed with the sperm. At this time, the lab begins thawing and growing her endometrial cells.
5. Once fertilization is confirmed, the patient's embryos are placed on top of her own (and now thawed) endometrial cells.
6. Over the next two days, the embryos are closely monitored for growth and development.
7. The patient's embryos are transferred into her uterus for implantation and pregnancy.
The risks of Coculture are minimal. The procedure has been performed in over 1000 patients with no reported detrimental effects on embryo growth. Complications involving uterine infection or damage caused by embryo biopsy are extremely rare.
Why don't all IVF centers use coculture?
There are several reasons that coculture is not currently more widely used for human IVF:
Coculture involves a lot of tedious work in the laboratory which leads to additional expense.
Most IVF labs are not experienced with culture of cells other than eggs, sperm, and embryos. Although culturing cells from the endometrium or fallopian tube is not extremely difficult, it does involve learning some new techniques.
There is not universal agreement that coculture is necessary to provide optimal pregnancy rates from human in vitro fertilization.
Another issue is that depending on the source of cells used for the coculture there may be concerns about transmission of infectious diseases such as viruses from the cell line to the developing embryos. To date there have been no reported cases of viral transmission to a human fetus. Non-autologous cell lines should be screened for infectious diseases prior to use in human embryo coculture.