oocytes

Today, many women they postpone motherhood until well past 30. The search for advancement in one’s professional career, work-life balance problems or economic instability tend to be the main causes why the average age of motherhood in Spanish women is now over 32 years old. In reality, in many cases, everything starts from economic instability. It is the reason why many women wait until they are successful in their careers to have children and also the reason why they cannot financially afford to pay people to help them take care of their babies without having to exploit grandparents. In short, having a child is expensive, so it takes many years to save enough. Unfortunately, the longer motherhood is postponed, the more difficult it is to achieve pregnancy and the greater the risk that the baby will be born with certain chromosomal syndromes. Oocyte freezing is often offered as a solution, but this is also expensive. If there is no money to have children, there may not be any to freeze oocytes when they are still young enough. Therefore, the proposal by a team of scientists from the Czech Republic, Germany and the United Kingdom to rejuvenate oocytes with the help of a single protein seems most promising. A protein to rejuvenate them all. One of the main reasons why fertility problems occur as age increases is the appearance of errors in meiosis. The authors of this researchwhich was presented last January at the British Fertility Conference in Edinburgh, they realized that there is a protein called Shugoshin 1, which has the ability to prevent precisely those errors in meiosis. By microinjecting this protein into oocytes donated to a fertility clinic, the effects on meiosis decreased, going from 53% in untreated oocytes to 25% in treated oocytes. For this reason, these scientists are already seeking the necessary permits to carry out clinical trials with patients who are going to undergo an in vitro fertilization (IVF) process. Clarification here: Although colloquially we always talk about eggs, the egg is the final maturation phase of the oocyte, which normally ends if there is fertilization. Therefore, what is donated or extracted for an assisted reproduction cycle is an oocyte. What happens in meiosis. Meiosis is a cellular process by which one cell divides into four others, with half as many chromosomes as the original. It is very important in sexual reproduction, since eggs and sperm are obtained which, when they fuse, add their chromosome ends and give rise to a zygote with the original number of chromosomes that human cells have. That is, if humans normally have 46 chromosomes, the egg produces 23 and the sperm produces the other 23. The two parts of meiosis. This process has two parts, each composed of several phases. Broadly speaking, after an initial crossing over phase to give rise to genetic variability, the pairs of chromosomes are placed in an orderly manner in the center of the cell. Afterwards, each member of the pair moves to one pole of the cell, so that it divides into two equal ones. Each of these cells will have one member of each pair of chromosomes. Those chromosomes that have separated still have two chromatids, with the characteristic X shape with which they are usually represented. Thus they reach the second part of meiosis in which the process is repeated again. All the X-shaped chromosomes go to the center of the cell. Then, a chromatid from each chromosome goes to each pole of the cell, which divides as before. Each of those chromatids will be a chromosome in the new cell. Thus, in the end, there will be four cells with half as many chromosomes as the initial one, although only one thrives to finally become an egg. The problems of age. There are several problems by which age can affect meiosis. However, it has been seen that the Shugoshin 1 protein has an essential role, since it acts as a kind of glue, preventing chromosomes and chromatids from separating prematurely or in an inappropriate way. That is why they wanted to test the experiment that has given these scientists such good results. A limitation. Success rates in IVF They usually begin an increasingly rapid decline after the age of 35. For this reason, these scientists wanted to make a distinction in their study between oocytes from children and adults of that age. Although the average was what we have already mentioned (change from 53% to 25% defects), with oocytes from over 35 years of age it only went from 65% to 44%. It’s not that statistically significant. However, there were only 9 oocytes in that age group, so it was not a sufficient number to draw conclusive results. Be that as it may, with the total it is clear that this protein can be very beneficial. It shouldn’t be frozen. Oocyte freezing It’s a strategy which is used to keep these cells in a more youthful state. If a 25-year-old woman freezes her oocytes, but decides to have children at 30, she can use those oocytes, which will have more or less maintained the qualities of the 25-year-old, and undergo an assisted reproduction process in which it will be easier to achieve pregnancy. The problem is that, at least in Spain, the price of freezing oocytes It can range between 2,000 and 5,000 euros. If a woman is not financially ready to have children at 25 or 30, she may not be ready to pay that sum of money either. In search of the clinical trial. Microinjection into oocytes already exists among assisted reproduction techniques. It is carried out through ICSI, a tool that consists of microinjecting the sperm directly into the oocyte. It is very useful in case there are few sperm and/or they are not very mobile. That makes clinics ready to microinject the Shugoshin 1 protein into oocytes. Even so, logically, the viability of this process must be tested. That is why the authors of the … Read more