Over the past 15 years there have been great advances in the field of IVF. Thanks to new technologies and procedures, IVF treatments are now becoming more and more successful, even for couples with a poor fertility prognosis.
Introduced in the 1990s, assisted hatching is a procedure that can help to improve your chances of IVF success. Available at most fertility clinics nationwide, the procedure is specifically recommended for couples who are most at risk for poor IVF outcomes.
What is Assisted Hatching?
Assisted hatching is a relatively new technique used during certain IVF procedures. It is performed in order to help an embryo hatch out of its protective layering and implant into the uterus.
During the initial stages of development, your embryo is contained in a layer of proteins, known as the zona pellicuda. The zona pellicuda is designed to protect the embryo until it reaches the blastocyst stage of development.
In order to successfully implant into the uterine lining, the embryo needs to hatch out of this zona pellicuda and attach to the walls of the uterus.
Sometimes, embryos have a difficult time hatching out of their protective layer. This can occur if the zona pellicuda is too thick or if the embryo does not have enough energy to break through the layer. Assisted hatching attempts to help these embryos break out away from the zona pellicuda by creating a small hole in this outer lining.
How is Assisted Hatching Performed?
Assisted hatching is a very delicate procedure, requiring immense skill. It is performed using micromanipulation techniques, under a microscope, during the fourth day of embryo development.
The embryo is first placed in a petrie dish containing culture solution. A special pipette is then used to hold the embryo in place. The embryologist takes a hollow needle that contains an acidic solution and places it next to the zona pellicuda.
A tiny bit of this acidic solution is released from the needle so that it comes into contact with the zona pellicuda. This acidic solution begins to slowly digest the protective layering, creating a small hole. The embryo is then washed in a special solution and placed back inside an incubator until embryo transfer can take place.
Who Can Use Assisted Hatching?
Assisted hatching techniques aren’t suitable for every couple. Instead, the procedure is typically recommended for:
- women over the age of 37
- women with elevated FSH on day 3 of their menstrual cycle
- couples who have experienced failed IVF cycles
- couples whose embryos have a particularly thick zona pellicuda
Risks Associated with Assisted Hatching
Unfortunately, there are some risks associated with assisted hatching procedures. In particular, assisted hatching procedures do seem to increase the likelihood that you will have identical twins (also known as monozygotic twins).
This is because the micromanipulation technique used to break through the zona pellicuda can sometimes cause the embryo to split into two identical halves.
There is also an increased risk of:
- damage to the embryo, potentially causing death
- fetal complications
- physical deformity
- conjoined twins
The procedure can sometimes also cause complications for the mother, including:
- high blood pressure
- mood swings
These side effects are the result of the steroids and antibiotics that you must take during the transfer procedure. Because the protective layer surrounding the embryo has been compromised, it is essential that you take medications to slow your immune system down and to prevent infection of the embryo.
Advantages of the Assisted Hatching Procedure
Many couples elect to pursue assisted hatching during their IVF procedures. This is because the technique is associated with a number of benefits including:
- fewer embryos required for transfer
- increased implantation success rates
- allows for blastocyst culture
Disadvantages of the Assisted Hatching Procedure
Unfortunately, assisted hatching does have its drawbacks. Specifically, assisted hatching is:
- only suitable for certain groups of women
- very difficult to perform and requires immense skills
- can be associated with an increased risk of dangerous pregnancy complications
Success Rates of Assisted Hatching
Assisted hatching is associated with a fairly high success rate, especially when performed by a skilled micromanipulator. In fact, pregnancy rates are as high as 49% in women who are between the ages of 35 and 39.
Women who are over the age of 40 generally have lower success rates, but assisted hatching still provides them with a better opportunity for conception than would IVF performed without the procedure.