Endometrial Biopsy
An endometrial biopsy is done to evaluate the development of the lining of uterus (endometrium) in relationship to ovulation. Routinely performed 7-10 days after a positive LH surge test, this test determines if the lining of the uterus is developing at the expected rate. Because a catheter is inserted into the uterus and a sample of the uterine lining is obtained, it is extremely important that you are not pregnant: this procedure has a 5% chance of disrupting an early pregnancy. It for this reason that you have been advised to avoid or have only protected intercourse during this cycle.
To help minimize the discomfort associated with the procedure, we suggest you take two Aleve (440-550mg) or three to four Motin/Advil/Nuprin (ibuprofen 600-800mg) one hour before the biopsy. Just prior to the biopsy, a topical anesthetic may be applied to the cervix followed by cleansing with an iodine-based solution. If you are allergic to novocaine, betadine, iodine, or shellfish, please notify the doctor prior to the procedure. Once the anesthetic has had time to become effective, an instrument is placed on the cervix to hold it in place while a small plastic tube (catheter) is inserted through the cervical canal and into the uterus. It is normal to experience moderate to severe menstrual-like cramps when the catheter enters the uterus and while the biopsy is being taken, but this usually takes no more than 10-15 seconds.
Once the catheter is removed, the cramping resolves quickly. If adequate tissue has been obtained, the procedure is complete. We advise you to avoid intercourse for two days after the procedure and call us if you experience any excessive or prolonged bleeding, temperature in excess of 100.6 degrees, pulse rate greater than 100 or excessive or prolonged pain.
PGS Pre-implatation Genetic Screening
PGS (also known as aneuploidy screening) involves checking the chromosomes of embryos conceived by in vitro fertilisation (IVF) or intra-cytoplasmic sperm injection (ICSI) for common abnormalities. This avoids having abnormal embryos transferred to the womb during IVF or ICSI.
How does PGS work?
The procedure for PGS is usually as follows:
Step 1. You undergo normal IVF or ICSI treatment to collect and fertilise your eggs
Step 2. The embryo is grown in the laboratory for two to three days until the cells have divided and the embryo consists of about eight cells.
Step 3. A trained embryologist removes one or two of the cells (blastomeres) from the embryo.
Step 4. The chromosomes are examined to see how many there are and whether they are normal.
Step 5. One, two or three of the embryos without abnormal numbers of chromosomes are transferred to the womb so that they can develop. Any remaining unaffected embryos can be frozen for later use.
Step 6. Those embryos that had abnormal chromosomes are allowed to perish or may be used for research (with your consent).
Possible variations to this procedure
There are possible variations to this procedure and the trophectoderm biopsy technique can be used in some cases.
Testing at five to six days
It is possible that instead of removing and testing one or two cells from a two – three day old embryo, some centres may allow the embryo to develop to five – six days, when there are 100-150 cells.
More cells can be removed at this stage without compromising the viability of the embryo, possibly leading to a more accurate test.
Alternatively some centres may test eggs for chromosomal abnormalities before they are used to create embryos. Polar bodies (small cells extruded by eggs as they mature) can be extracted and tested.
Comparative Genomic Hybridisation (CGH)
A small number of clinics are now using a procedure called comparative genomic hybridisation (CGH) which allows centres to test for abnormalities in all 23 chromosomes.
These abnormalities may or may not be of biological significance, but their presence will lower the chance of finding suitable embryos for transfer.
