Laser-assisted hatching
Laser-assisted hatching is a scientific IVF technique that can make it easier for the embryo to “hatch” or breakthrough its outer layer or “shell” (a membrane also known as the zona pellucida) by creating an opening. In some situations, this layer is abnormally thick and/or hardened with the freezing and thawing process among the contributing factors. The less difficulty the embryo has in hatching, the better its chance of attaching or implanting into the wall of the uterus. Pregnancy cannot occur unless the embryo hatches and implants, and laser-assisted hatching can play a key role in achieving these crucial steps.Treatment procedure
The procedure involves an embryologist sending a brief, strong light beam, under a microscope, to create a gap in the shell through which the embryo can come out. This is usually done three days after fertilisation has occurred during an IVF or Intracytoplasmic Sperm Injection (ICSI) cycle, which is when the embryo has begun to cleave (divide). It takes only a few seconds and does not harm the embryo. The embryo is then transferred back into the patient’s uterus to attach itself to the lining and continue growing.Who is assisted hatching recommended for?
Any patient can take advantage of laser-assisted hatching, but those most likely to be best suited are those who:- Are above the age of 37
- Produce a high level of Follicle
- Stimulating Hormone (FSH) early in their cycle
- Have had unsuccessful IVF cycles
- Have a tendency to produce a harder and/or thicker zona pellucida
Advantages of laser-assisted hatching
A laser has been shown to be superior to other forms of assisted hatching (chemical and manual) thanks to several advantages:- Minimal handling of the embryo
- Fast and exact control over drilling of the shell opening
- It is gentle and safe, with no negative effects on the embryo
- Wide availability to patients, and offered under clinical guidance depending on your particular circumstances
The disadvantage is that fewer embryos will “survive” or grow to this phase (probably about 30%-50% of them). There is a possibility (up to 10%) that none will reach the blastocyst transfer stage and therefore no embryos will be available for transfer. The availability of “extra” embryos for freezing is also significantly reduced.
Blastocyst embryo transfer – treatment procedure
IVF embryos are usually transferred on the second or third day after egg retrieval, at the four to eight-cell stage. The IVF embryos must continue to grow for two or three more days to reach the blastocyst transfer stage (100-150 cells) before they are ready for implantation into the uterine wall (endometrium).
Blastocysts may have greater potential to implant into the uterine wall than earlier-stage embryos. Many embryos stop growing at the four to eight-cell stage, probably because of some inherent problem. Therefore, fewer embryos will have the ability to grow to the blastocyst stage. Those that successfully reach this stage are probably more developmentally competent than earlier-stage embryos. In addition, their stage of development, when replaced into the uterus, is very similar to what it would be in a natural conception cycle.
The potential improvement in fertility that this type of treatment may yield depends on the woman’s age, diagnosis and partner’s initial semen analysis, and should be discussed with your specialist.
Who is blastocyst embryo transfer recommended for?
Couples who have had unsuccessful attempts with IVF or IVF-ICSI despite having many good-quality eggs retrieved are being offered blastocyst culture as an alternative treatment. Couples with multiple good-quality embryos on day 3 are also strong candidates for blastocyst culture. The ability to select the most viable embryos for transfer and implantation should improve these couples’ chance of achieving a pregnancy.
What are the potential risks?
In a small number of cases (less than 10%), none of the embryos develop into blastocysts and therefore no embryo transfer is performed. This might signify an inherent problem with the embryos.