Preimplantation genetic diagnosis (PGD) is a technique that is performed within an in vitro fertilization cycle, prior to embryo transfer, in order to detect genetic and chromosomal abnormalities in embryos and select those that are healthy.

To analyze the genetic material it can be obtained from oocytes or resulting embryos, depending on which genetic alteration or chromosone we want to determine.

When

  • One or both partners are carriers of hereditary genetic disease
  • One or both partners are carriers of a genetic condition (translocations, inversions, etc..)
  • Repeated failure in conventional cycles using IVF or ICSI
  • Repeated failure implantation of embryo
  • Repeated abortions
  • Advanced maternal age without fertility preservation
  • Background of abortion and / or pregnancy with chromosomal abnormalities
  • Some cases of male sterility
  • HLA Typing

Phases

The steps are the same as for an IVF cycle, only at one point in the cycle there shall be biopsied or oocytes or embryos to extract the genetic material to analyze.

Ovarian stimulation
We begin treatment with ovarian stimulation, where we use a number of hormones similar to those produced by the woman herself (gonadotropins). The goal is the development of multiple follicles to obtain a high number of oocytes and thus increase the chances of success. The stimulation is regularly monitored by ultrasound and blood tests.
Ovulation induction

After several follicles have reached the right size (18 mm aprox) HCG hormone is administered to trigger final oocyte maturation, which will occur after 34-36 hours and that is when will be performed the follicular puncture.

Follicular punction
Under sedation, the fertility specialist removes mature oocytes by follicular puncture and vaginally. The oocyte retrieval is a minimally invasive procedure that normally takes less than 15 minutes. Generally, patients can resume normal activities the next day.
Sperm capacitation

The day of the follicular puncture, the andrologyst prepares male sperm sample, by selecting the sperm that have more mobility by washing techniques.

Insemination of oocytes
Depending on the alterations or chromosomal genetics to be analyzed and / or semen quality we will proceed with the insemination of oocytes by conventional IVF or ICSI.
Polar corpuscles biopsy
The oocyte produces two small cells called polar corpuscles whose genetic content is similar to the oocyte. With the analysis of polar corpuscles only will be obtained information of the genetic contribution of the women. There will not be detected or paternal chromosome abnormalities or those that may arise after fecundation. To make a polar corpuscle diagnosis it is necessary to make a hole in the deck surrounding the oocyte (pellucid zone) and extract the corpuscle with a pipette. This will be analyzed when the inseminated egg remains in the incubator pending the diagnosis.
Fertilization and embryo culture
The day after insemination, fertilization is observed in the oocytes. Those who have been properly fertilized will be kept under observation in the laboratory for several days (between 2 and 5 days). Day after day we will be watching the embryos dividing and increasing its number of cells.
Blastomeres biopsy
The embryos are made of cells called blastomeres. To perform a genetic analysis of blastomers, we have to make a hole in the cover surrounding the embryo (pellucid zone) on day 3 of embryonic development, when it has between 6 and10 cells. With the help of a pipette the cell is aspirated and while being analyzed, the embryo will be maintained in cultivation in the incubator.
Embryo transfer
Embryos that have, after genetic analysis, normal genetic and chromosome endowment and / or adequate morphological characteristics will be transferred to the womb, and if there are healthy embryos leftover we will proceed to freeze. The day of the transfer we will decide the appropriate number of embryos to be transferred, those can not be higher than three per cycle. The gynecologist uses a small catheter to guide the embryos through the cervix and deposit them. The embryo transfer procedure lasts a few minutes and the recovery time for the patient is minimal.
Luteal phase support
To facilitate embryo implantation progesterone is administered vaginally to help support the luteal phase.
Pregnancy test

The pregnancy test will be done through a blood test 13 days after the follicular puncture.

If the patient has lost blood before undergoing the test it is important to never leave the medication and to contact the medical team for advice. Throughout treatment, your personal assistant will be available at all times to resolve any doubts that you may have and support you in this special moment.

Fertility clinics in Spain

Medical Team

Susana Sempere - Gynaecology

Dr. Susana Sempere Ferri

Antonio Moya - Reproductive Medicine

Dr. Antonio Moya

Eva Moreno

Dr. Eva María Moreno Ruiz

Jose Manuel Lozano - Gynaecology

Dr. Jose Manuel Lozano

Romina Ramírez - Gynaecology

Dr. Romina Ramírez Melguizo

You know what…

  • So far, about 1000 babies have been born worldwide using PGD. The first pregnancy achieved in Spain was in 1994, in a couple where the patient was a carrier of hemophilia.
  • According to Spanish legislation it is only possible sex selection for therapeutic purposes, to avoid sexual diseases X-linked (hemophilia, Duchenne muscular dystrophy, fragile X syndrome).
  • For patients indicated for this technique there is an increase in the rate of pregnancy. With PGDincreases the probability of survival of the embryo, as if it had some kind of genetic or chromosomal defect probably would not be viable.
  • Usually after the transfer, the patient waits about an hour in the room of the Center for Assisted Reproduction. If your gynecologist does not specify so you do not need rest after the transfer. There are no studies which show that rest increases the chances of getting pregnant. Then, once at home, she can perform a normal life.

Information about Preimplantation Genetic Diagnosis (PGD) in Spain