IVF and ICSI can be very successful treatment methods. However, some cycles don’t finish with successful implantation, even after a number of transfers with apparently good embryos. Also, sometimes a cycle achieves a conception, but the pregnancy doesn’t develop to term. There are various biological reasons why these two circumstances could be related, which lead us to look at potential therapies which could help.
Investigations and treatments
There is support for several treatment options for women with “recurrent implantation failure” (defined as 2 or more failed embryo transfers in IVF/ICSI treatment cycles). However, the available evidence is limited for many of the possibilities, due to a lack of suitably large clinical studies. Listed below are options we can talk about in a follow-up appointment in the upsetting event of a failed implantation or miscarriage. In devising treatment programmes, there are investigations we can carry out before treatment commences, which help us to tailor your treatment closely to your needs. There are also options carried out in the process of treatment that could help implantation.
If you’d like to talk about your options after an implantation failure or miscarriage, we’re here to help.
Maternal blood tests
- Clotting (thrombophilia) screen – Small clots in the blood have been identified as a possible cause for a pregnancies failing to progress. In some cases this can be treated with aspirin, or heparin injections to thin the blood.
- Immune screen – Increased levels of uterine natural killer cells (white cells) and autoantibodies (antibodies attacking specific organs) have also been suggested as a cause for repeated failure of cycles. The use of steroids, intralipids and other drugs to suppress the immune system and to help a pregnancy develop are controversial. More clinical trials are needed to understand the ways in which the immune system affects pregnancy and which treatments might benefit which women). Some of the drugs used in these treatments have side effects for both a mother and her developing baby, and it’s important to understand these risks before deciding with your doctor whether testing or treatment is recommended.
- Hysteroscopy or endometrial scratch – We may suggest a hysteroscopy (passing a flexible telescope into the womb under general anaesthetic) if we suspect scar tissue formation or the presence of a fibroid or polyp inside the womb which needs to be removed. There is some evidence that this procedure itself, or performing an endometrial scratch, can increase implantation rates.
- Endometrial Receptivity Array – A small amount of tissue from the womb lining (endometrium) can be sampled and analysed for the presence of over 200 genes known to be associated with implantation. Studies have shown that for some women this “window of implantation” is shifted either earlier or later in the menstrual cycle, or it is very narrow. Furthermore, by moving the planned embryo transfer to the appropriate time, chances of successful implantation can be improved.
- Sperm DNA fragmentation – Assessing the degree of damage to sperm DNA help identify those couples that would benefit from ICSI treatment.
- Genetic screening – We can use genetic screening to learn more about embryos before they are implanted, which helps us select the best embryos most likely to implant.
- Embryoscope™ (Time-lapse imaging) – Recording information by time-lapse photography allows us to assess more subtle changes seen during embryo development and identify the best embryos for transfer.
- Laser-assisted hatching – Assisted hatching is a physical or chemical treatment carried out immediately before embryo transfer. It weakens an area of the zona pellucida (the embryo’s ‘shell’) with the aim of improving the chances of implantation. We use a laser, as it is considered to be the safest and most accurate method.