Our New Jersey fertility specialist explains implantation failure
Jane Miller MD utilizes her experience and the latest techniques in reproductive medicine to help patients achieve successful pregnancies, but sometimes implantation failure can occur. The key to overcoming this hurtle to pregnancy is to understand more about how and why embryos implant in the uterus – and what can interfere with this process.
The difference between embryo transfer and implantation
During in vitro fertilization (IVF), our New Jersey fertility specialist does not implant embryos in the patient’s uterus – she transfers them. By performing embryo biopsy and preimplantation genetic screening (PGS), we can select genetically normal embryos to transfer to a designated location in a woman’s uterine cavity. Implantation, which is a process that occurs between the embryo and the endometrium (uterine lining), occurs after transfer.
The causes of implantation failure
Many patients want to know why all euploid (genetically normal) embryos don’t implant and grow into a successful pregnancy? The national average for successful implantation and pregnancy after the transfer of a genetically normal embryo, as determined by PGS, is 66%. Why is it not 100%?
Our New Jersey fertility specialist explains that implantation failure can occur because of problems with the embryo and/or the uterine environment.
When it comes to the embryo, there are two ways to tell if it has the potential to implant and grow into a baby, including PGS and the embryo grade.
- PGS will tell us if an embryo has the correct chromosomal makeup to develop into a healthy baby.
- The embryo grade (the scoring assigned by the embryologist) will tell us if there are enough cells to make a baby. The number of these stem cells is denoted by letters of the alphabet. A’s and B’s have good developmental potential, but A-grade embryos have a slightly better chance of success than B-grade ones. C’s and D’s should not be transferred to a woman’s uterus as they are unlikely to result in an ongoing pregnancy. In addition, embryos that reach their full expansion by Day 5 have a 10% higher chance of implanting than those that reach this stage by Day 6.
As for the uterine environment, our New Jersey fertility specialist explains that mechanical problems within the uterine cavity can cause implantation failure.
- Uterine polyps or fibroids that are within or close to the uterine cavity, uterine septa (midline walls) or other defects of the uterine architecture can prevent implantation or cause an early miscarriage of a normal pregnancy.
- Inflammatory problems, including endometriosis and hydrosalpinges (fallopian tubes that are closed and filled with watery secretions), can prevent the uterus from being receptive. Specific protein markers for these inflammatory conditions as well as markers for uterine receptivity can be assessed with an endometrial biopsy and an analysis of the tiny sample of cells from this biopsy using the ReceptivaDx test.
- Infections can cause implantation failure in a perfectly healthy embryo. An endometrial biopsy can be used to see if a woman has an infection in the uterine lining (endometritis).
Not only can an endometrial biopsy identify inflammatory problems and infections in the uterus, it can also determine the best time to transfer an embryo. The endometrial biopsy, when combined with the ERA test, can identify a woman’s individual implantation window to determine the optimal day for embryo transfer.
Individualized fertility care to combat implantation failure
Our New Jersey fertility doctor believes that taking a careful, detailed patient history can help diagnose problems with embryo genetics, embryo grade and uterine receptivity. She can then offer appropriate testing to patients and, once diagnosed, provide treatment for these problems before an IVF cycle to improve a woman’s chances of achieving pregnancy success.
Contact our New Jersey fertility specialist to schedule an appointment and learn more about the causes of implantation failure.