ICSI (Intracitoplasmic Sperm Iniection) is a medically assisted procreation technique developed in 1976, but we have to wait until 1992 to see it used on humans thanks to the Italian Giampiero Palermo.
Nowadays it is the most used technique in MAP, not only in cases of severe male infertility and in cases of previous IVF failures.
It is basically very similar to IVF except that in this case there is no spontaneous fertilization by one of the many spermatozoa with which the egg is incubated, but there is intracytoplasmic injection of a single good quality mature spermatozoon into the oocyte (after specific treatment).
When is ICSI used?
The indications to the ICSI are
- Severe male infertility;
- obstructive and secretory azoospermia (testicular or epididymal sperm retrieval)
- lack of or reduced fertilization in previous cycles of in vitro fertilization (IVF)
- thawed oocytes;
- reduced number of oocytes;
- cryopreserved semen in relation to semen quality after thawing.
There is a tendency to resort to ICSI more and more often even in the absence of these indications there is no evidence that using this technique improves fertilization rates, pregnancy rates and the percentages of children born.
How does ICSI happen?
ICSI is very similar to IVF in the first part, up to the egg pick-up. While in IVF the spermatozoa, capacitated, are put in contact with the oocytes, in ICSI, the spermatozoa are selected one by one. Each selected sperm is microinjected into the cytoplasm of the oocyte.
Practically with ICSI the process of natural selection that occurs in IVF, such as sperm-oocyte recognition and the penetration of the sperm into the egg cell, is completely skipped.
The overall procedure includes:
- spontaneous cycle or with induction of follicular growth and maturation of several oocytes by administering ovulation-inducing drugs;
- control of the ovarian response to such therapy by ultrasound monitoring and / or estradiol dosage;
- egg retrieval transvaginally, under ultrasound control, under local anesthesia and / or deep sedation, or laparoscopic or transabdominal sampling in cases where the trans-vaginal technique is not applicable;
- possible identification of the oocytes to be donated (egg sharing) for the purposes of assisted procreation of the heterologous type;
- preparation of the semen sample;
- removal of the cumulus-crown complex in oocytes;
- insemination oocytes by intracytoplasmic microinjection technique of a single spermatozoon;
- verification of the successful fertilization of each oocyte;
- transfer of embryos to the uterus.
In the case of azoospermia, one of the following techniques is used to obtain sperm:
- Percutaneous Sperm Aspiration by Testicular Route (TESA),
- Sperm extraction by testicular route (TESE and micro-TESE),
- Microsurgical Aspiration of Sperm from Epididymus (MESA),
- Percutaneous Aspiration of Sperm from Epididymis (PESA);
Before proceeding for ICSI for severe male infertility it is essential that the couple be prescribed genetic tests and genetic counseling. It is usually required
- male karyotype
- genetic testing for cystic fibrosis. screening for cystic fibrosis is particularly suitable for those suffering from azoospermia
- test for the detection of microdeletions of the Y chromosome in selected cases characterized by azoospermia or severe oligozoospermia (<5 million / ml)
The latest annual data collected by ESHRE from European national registries (for 2016) show an increase in the cumulative use of IVF in infertility treatment.
Success rates after IVF or ICSI appear to have peaked, with pregnancy rates per treatment of 27.1% after IVF and 24.3% after ICSI.
Despite this, from ESHRE data, clinics in Europe continue to favor ICSI over in vitro fertilization with a ratio of about two to one (359,858 ICSI and 128,626 IVF), a trend that reflects what happens in the rest of the world.
ICSI and congenital anomalies in children
There is currently little long-term follow-up data on the health of babies born with this technique.
The study of congenital anomalies or malformations in children born thanks to assisted fertilization techniques has brought controversial results. There appears to be an increased risk of congenital anomalies in infants born with IVF compared to those conceived naturally.
It remains to be seen whether the increase in these anomalies is related to the technique or to the altered quality of the paternal seminal fluid.
GUIDELINES CONTAINING THE INDICATIONS OF MEDICALLY ASSISTED PROCEDURES AND TECHNIQUES Art. 7 – Law no. 40/2004 2015 GUIDELINES
Lazaraviciute G, Kauser M, Bhattacharya S, Haggarty P, Bhattacharya S. A systematic review and meta-analysis of DNA methylation levels and imprinting disorders in children conceived by IVF / ICSI compared with children conceived spontaneously. Hum Reprod Update. 2014 Nov-Dec; 20 (6): 840-52. doi: 10.1093 / humupd / dmu033. Epub 2014 Jun 24. Erratum in: Hum Reprod Update. 2015 Jul-Aug; 21 (4): 555-7. PMID: 24961233.
The Practice Committees of the American Society for Reproductive Medicine and Society for Assisted Reproductive, TechnologyIntracytoplasmic sperm injection (ICSI) for non-male factor infertility: a committee opinion, ASRM PAGES | VOLUME 98, ISSUE 6, P1395-1399, DECEMBER 01, 2012, https://doi.org/10.1016/j.fertnstert.2012.08.026
Wen j, Jiang J, Ding C, Dai J, Liu, Xia Y, Liu J. Hu Z, Birth defects in children conceived by in vitro fertilization and intracytoplasmic sperm injection: a meta-analysis, Fertility and Sterility Volume 97, Issue 6 , June 2012, Pages 1331-1337.e4, https://doi.org/10.1016/j.fertnstert.2012.02.053