Embryo development

After fertilization an embryo develops from the egg cell. The subsequent hours and days of development are decisive for the success of the treatment. There are continuous improvements made regarding the embryo culture. Incubators are constantly being improved in order to provide the perfect surroundings for the embryo, meaning a close replica of the conditions found in the body of the woman. The culture medium, in which the embryos are situated, is also continously enhanced. Nevertheless, embryos from different couples vary and occasionally even embryos from the same couple and treatment cycle differ greatly from each other.

Poor embryo development

Poor embryo quality means that in the days following fertilization the embryo divides too slowly or there is a cessation in development.  Furthermore, one can determine the quality of the embryo in the laboratory (score) and based on several parameters (irregular size, fragmentation of the cells) establish the likelihood of nidation.

Possible causes

  • Profoundly reduced sperm quality (ie. Cryptozoospermia or use of testicular sperm)
  • Reduced egg cell quality (ie. advanced age of the mother, hormonal disorders, poor response to the stimulation process, high body weight)
  • Genetic faults in the embryo
  • Infections

Clarification

Should a decreased embryo development result from an IVF treatment, the chance of success are diminished. Nevertheless, if the embryos have not completely stopped their development, the continued attempt should be made to achieve further development. If pregnancy does not occur we will search for other possible causes using a variety of investigative methods such as:

  • a complete hormonal status including a thyroid stress test (TRH-Test)
  • a semen analysis evaluation together with a bacteriological examination of the ejaculate and advanced diagnostics (Hyaluronic acid binding test followed by possible examination of the sperm cells)
  • a chromosomal examination of the couple (cytogenetics)

Therapeutic possibilities

Depending on the results, a number of therapies are at our disposal:

  • Infections of the prostate
    -> must be treated with antibiotics for a sufficient period of time.
  • In case the sperm obtained are of a very low quality
    -> a sperm sample can be taken directly from the testicle (testicle biopsy – TESE)
  • If thyriod dysfunction occurs (i.e. hypothyrosis)
    -> optimal adjustments through a thyriod specialist
  • If the chromosome examination reveals genetic abnormalities
    -> any further prognoses will be made depending on the findings of this genetic examination. In some cases, a pre-implantation diagnosis offers advantages.

In order to optimize the ripening of the egg cells during the stimulation process, we recommend the alternation of the stimulation scheme and the hormonal preparation. Depending on the hormone findings, it may be useful to compensate for any irregularities.

Therapeutic rudiments in our institute:

  • embryo cultivation in different culture mediums
  • the addition of various fertilization techniques (pICSI, IMSI, etc.) can improve the embryonic culture
  • Egg donation for repeated stops

In-vitro maturation (IVM)

The egg follicle and the egg cell are a special and tightly connected unit. As a result of the follicle growth in the last few days prior to ovulation and egg cell removal, the egg cell undergoes the last decisive ripening. Thereby, it can be fertilized and subsequently develop into an embryo. In these rare cases in vitro maturation (IVM) may be applicable. This means no hormonal stimulation of the follicles. As a result, no follicles grow and the egg cells within do not ripen. These unripe egg cells are removed from the small undeveloped follicles and then ripened in the laboratory. Hence the name of the method:  “Glass Ripening.” This is followed by fertilization via IVF or, usually, ICSI, the routine preparation of the embryo culture and, finally, the embryo transfer.

The IVM is suitable for patients, where

  • a routine treatment was not successful
  • a high risk could occur with another hormonal stimulation side effects

The IVM is NOT suitable for patients, that

  • have a low or no response to the stimulation. In these cases there are even the small, undeveloped follicles are missing which include the egg cells for the ovum pick-up.