Scratching your way to pregnancy- Endometrial biopsy before IVF

endometrial-biopsy-princeton-ivfIn recent years, endometrial scratching, irritating the endometrium (lining of the uterus) to help in making the womb more receptive for pregnancy has emerged as a new and unsual way to help couples get pregnant.  Recently, a group from Turkey presented data at the American Society of Reproductive Medicine meeting suggesting that performing an endometrial biopsy prior to IVF can improve pregnancy rates in women undergoing IVF by about 20%. In fact over the years, seeming against common sense, there have been a number of studies suggesting  that a biopsy and/or hysteroscopy may improve the chances for IVF success. At Princeton IVF, we have been using this technique for years, first in patients who failed cycles without any good explanation and then routinely in all our IVF patients. Although no one is quite sure why it helps, it is likely that the repair process from endometrial trauma helps to make the uterus more receptive to embryos.

Do embryos and the uterus talk to each other?

blastocyst-embryo-pivfWe know that in normal fertile couples it takes an average of 3 months to conceive.  We also know that in successful IVF programs, most embryos will never implant.  Even when genetic testing is performed on the embryos to eliminate the most common cause of IVF failure, 30% of embryos will still not stick. So, is the embryo sending some sort of message to the uterus that is OK to allow implantation or not? Researchers from the UK, discovered that embryos produce an enzyme called trypsin that facilitates the implantation process, but that embryos which are genetically abnormal produce less trypsin. This may be a way that embryos tells the uterus whether it ok to allow implantation. Perhaps a better understanding of this process may help develop ways to make IVF more successful.

Ethnicity and IVF success rates

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A recent study from the UK showed what many Reproductive Medicine specialists noticed for some time, that a couples’ chances for success with IVF vary based on ethnicity. In this paper published in the British Journal of Obstetrics and Gynecology, IVF success rates varied by race with white women having the highest pregnancy rates, followed by women of Southeast Asian descent, then African descent and then Middle Eastern descent. The reason for this is not at all clear. The number of eggs women produced, how many fertilized and the number of embryos transferred, did not differ based ethnicity.  However the implantation rate (the percent of transferred embryos that took) did differ among the groups. Why the embryos of some ethnic groups would be more likely to implant than others remains the big unanswered question.

Weight does impact the chances for IVF success

We have know for years that being overweight can affect fertility and lower success rates for infertility treatments such as IVF. Some centers have even set weight limits on IVF treatment for this reason. However, it wasn’t clear if being overweight was harming the eggs or making the uterus less receptive to pregnancy. A recent study from Spain found that overweight patients had lower pregnancy rates even when they got eggs from a normal weight woman, meaning that this effect is due at least in part to a problem with the uterus. The take home lesson: weight loss may improve your chances of having a baby even with donor eggs. For more information from Dr. Sanjay Gupta’s Guide, click here