In Vitro Fertilization



In Vitro Fertilization (IVF) is one of the most widely used techniques in assisted reproduction today. The name of this procedure originates from the union of eggs and sperm in the laboratory, that is, a fertilization outside the woman’s body.

IVF is a fertility treatment in which the ovaries are first stimulated in a controlled manner over 8-12 days. In this way, the perfect development of several eggs can be achieved in order to extract them at the time of the follicular puncture.

The follicular puncture, or ovarian puncture, is performed in the operating room under very light sedation. The patient breathes autonomously at all times and remains asleep for approximately 15 minutes in order to extract the eggs from the follicles, without causing discomfort. The fertilization is then performed in the laboratory. 

It makes no difference to the patient, in fact, she will always have to undergo ovarian stimulation treatment to produce a good number of good quality oocytes.

Depending on the quality of the sperm and oocytes, biologists identify the most appropriate fertilization technique. That is, IVF or ICSI, with the option of doing a combination of both. Joining eggs and sperm in the laboratory to generate embryos.

fecundación in vitro

Conventional IVF

In conventional in vitro fertilization, sperm from the couple or from an anonymous donor are previously processed and deposited together with an oocyte. This type of fertilization technique is the closest to the one that occurs naturally because the fertilization of the egg by the sperm takes place by itself.

This means that oocytes and sperm are placed in the same physical space and it is left to chance which sperm will fertilize an oocyte. Insemination is performed with approximately 100,000 motile sperm per oocyte.

ICSI (sperm microinjection) 

In this case, the semen is also processed first, but it is the biologists who fish the sperm through a microneedle and introduce it into the oocyte. Thus intervening more actively in the fertilization process. The sperm is selected taking into account its morphological and motility characteristics.

The technique of sperm microinjection or ICSI is especially indicated in couples diagnosed with severe male factors. That is, when the patient’s partner has a low sperm count, reduced motility or abnormal morphology. 

Frequently asked questions

  • When is ICSI recommended? ICSI is indicated after a previous failure of a conventional IVF cycle and when the egg or sperm quality is low.
  • What is the success rate of IVF with ICSI? The fertilization rate of ICSI can reach up to 80% success rate. 
  • In what cases is conventional IVF used? The main requirement to perform this technique is to have a high seminal quality because this offers greater guarantees for the sperm to be able to fertilize the egg by itself.