One of the objectives of Assisted Reproduction (AR) is to strive to achieve the same benefits of natural reproduction, one of them being the birth of a single baby. In natural reproduction, multiple pregnancies only represent 1% of the total births. Therefore, the probability of having twins is very low. Also lower is the risk of complications for the mother and her offspring that often comes with these multiple pregnancies.
Ever since reproductive medicine emerged as one of the key components of Spain’s birth rate representing nearly 10% of all births, multiple pregnancies have grown as a result of these reproductive techniques. The probability of a multiple pregnancy rose to 30% after receiving a fertility treatment due to the use of ovarian stimulation drugs or through the transfer of more than one embryo after in vitro fertilization. (Multiple pregnancy recommendations from SEF. )
As the success rates from assisted reproduction began to exceed those of natural reproduction, and given the progress made in this medical area in recent years, fertility clinics have made great efforts to reduce the gap created between natural and assisted reproduction in terms of multiple births. In 2018, the clinics managed to reduce the multiple birth rate to 13%, a percentage that falls below the European average.
There are numerous reasons that explain why SET has become a trend that will end the multiple births associated with AR, and all are directly related to the health of the mother and her offspring. Science, however, provides the possibility for single transference to become a reality in the future for 99% of all women, thereby representing the same single birth rate provided in natural reproduction. “The current knowledge regarding embryos allows an optimal and predictive selection that was not possible a decade ago. We now know much more about embryo development and endometrial receptivity. We have always focused on the positive, but now we have the data and the tools to make that positive safe and sustainable,” explains Dr. Juan Giles about the future of multiple births.
SET and the importance of social awareness
When we look back in time, the existence of twins was a rare occurrence when we were younger. Over the past twenty years, however, this has changed. In almost all the schools in Spain, you will now find several pairs of twins, a situation which has caused us to normalize multiple births and pregnancies. In fact, in some cases of infertility, it is considered to be ideal when the desire to reproduce is met with so many limitations.
The gynecologists and the scientific community involved in Assisted Reproduction and the Maternal-Fetal field have done a great deal to educate people on the consequences of multiple pregnancies, given that they can be very serious for both the mother and her offspring. The following list of complications was published by the Spanish Fertility Society.
Complications for multiple offspring
- Delayed intrauterine growth
- Premature birth in 50% of twins and 90% of triplets
- Increased risk of neonatal morbidity and mortality
Complications for the woman carrying a multiple pregnancy
- Placental Anomalies
- Gestational diabetes
- Prolonged hospitalization for possible premature birth
- Performing a Cesarean Section
“In just 5 years, the Spanish fertility clinics have been able to reduce multiple births from 21% to 13%. Most likely, medicine will practically or almost completely end this problem in the 2020’s. We are making great strides in this area, and couples are becoming more and more aware of all of these risks,” concludes Dr. Giles.