Victor Montes de Oca G.
In the last 26 years I have dedicated myself to reproductive medicine, in the first years in the infertility clinic of the Department of Biomedical Research of Profamilia and from the year 2000 to date in front of Profert.
There is a desire of the couples who come to the consultation to have a multiple pregnancy. According to studies, between 67 and 90% of couples who consult for infertility want a twin pregnancy. I always tell our patients that multiple pregnancy is not our goal, but rather a complication of assisted reproductive treatments.
In this article I intend to guide you on the risks of multiple pregnancy and the strategies that we have implemented and will continue to improve to achieve what really matters, a healthy baby at home.
The chances of a couple having a double pregnancy naturally are 1.1%; that this is triple or more, 0.01%. Twin pregnancies, when they come from a single egg fertilized by a sperm and then subdivided into two, are known as identical twins (they are of the same sex and are a mirror image of each other). The pregnancies that come from the union of two ovules with two sperm (dizygotic) can be of different sexes and have the similarity that two brothers would have, but in this case they cohabit inside the mother’s uterus at the same time.
Techniques used
Las assisted reproductive techniques increase the chance of a multiple pregnancy. Within assisted reproductive techniques we have to talk about two groups: those of low complexity and those of high complexity.
In low complexity treatments we have the artificial insemination, which is nothing more than the use of drugs to stimulate the growth of more than one follicle, upon reaching a certain size, cause ovulation and, at a certain time, place the sperm, previously trained in the laboratory, inside the woman’s uterus. In this technique, the only control that the specialist has is to know the number of follicles that could be fertilized, since fertilization will take place spontaneously inside the woman’s body. In some cases there are follicles that had not reached the desired size at the time of firing and there is usually extreme multigestation (three fetuses or more).
In highly complex techniques we basically have two. The in vitro fertilization y embryo transfer (IVF-TE) and intracytoplasmic injection of a single sperm and subsequent embryo transfer (ICSI). It is on these two techniques and some variants that I want to focus my article.
Both in IVF-TE and in ICSI, the woman is subjected to the application of medications to produce what we know as controlled ovarian stimulation. We accompany this growth by performing serial pelvic sonographies and hormonal determinations, at the moment of finding follicles. of the desired size we trigger ovulation and in a certain time we will aspirate the follicles to obtain the ovules, which, depending on the technique to be used (this depends on the diagnosis), we will fertilize and cultivate until they are transferred to the uterus or vitrified (freeze ) for subsequent transfers.
Taking the data from the Latin American Registry of Assisted Reproduction, the organization to which we belong and report our cases, and since this is a tool that allows us to have information that helps us make decisions to guide our patients, I would like you to see the trends in the region . In the year 2000, of the highly complex cycles, four or more embryos were transferred in 43% of the cycles, three embryos in 27.3% (something unthinkable at present), two in 18.6% and transfer of a single embryo in 11.0%. For the year 2016 these are the percentages: four or more in 0.9% of the cycles, three in 12.3%, two in 61.3% and a single embryo in 25.4%.
The data shows a downward trend, but this not only occurs in Latin America, but we can see this same policy in the ESRHE and SART for Europe and the United States, respectively. Due to this policy we can see how in the year 2000 7.7% of births in Latin America were triples while in 2016 only 0.6%. In 2016, 79.9% of reported births were unique.
Why do we have to avoid multiple pregnancies?
Because of the complications that this type of pregnancy causes both the mother and the fetuses. From the point of view of maternal health, we have an increase in pregnancy-induced hypertension, diabetes, bleeding, greater number of cesarean sections, the mother’s probability of dying rises 2.5 times in relation to a singleton pregnancy. From the point of view of future children, there is a risk of abortions, low birth weight, prematurity, visual problems, cerebral palsy, sepsis and death.
In this way, when I see some colleagues on social networks posting photos and videos with multiple pregnancies and, above all, extreme multiplicity (three or more), I wonder if they are aware of the type of medical practice they are doing and how it affects the health of the population. To be honest, I think not.
What are the measures we have to take?
– Transfer only at the blastocyst stage (day 5).
– Transfer no more than two embryos.
– In patients with a good prognosis, the transfer of a single embryo.
– If you have the possibility of performing a preimplantation biopsy, elective transfer of a single embryo.