According to the World Health Organization (WHO), every year more than 20 million babies are born weighing less than 2,500 grams, the vast majority in developing countries.
Historically, assisted reproduction has been associated with the birth of low-weight babies, but the latest data emerging from a study conducted by IVI show that, for the first time since the arrival of in vitro fertilization (IVF) more than four decades ago, babies born using assisted reproduction techniques have a similar weight to those born naturally.
“We have worked hard to reverse the percentage of low birth weight babies and make it more in line with that obtained in spontaneous pregnancies to term, and today we can state that less than 8% of babies conceived in any of the IVI centres in 2019 presented low birth weight. Taking into account that, according to the latest figures dating back to 2017, the percentage in the case of naturally conceived babies stands at 7.8%, this is a promising figure that allows us to break down some of the stigmas that have marked our field of work. Our goal has been and continues to be to make assisted reproduction more in line with pregnancies achieved by natural methods, and figures like these show us that we are well on our way”, said Dr. Antonio Requena, Medical Director at IVI.
Not all babies born with low weight are premature. It is estimated that between 3-5% of full-term babies are placed at the bottom of the height and weight tables, which does not mean that they will have abnormal development.
“In just over 15 years, we have seen a threefold reduction in the risk of low birth weight in IVF babies. This reassures patients, as it is clear that today's IVF is no longer equivalent to premature twins who can spend weeks in the neonatal unit, but to a healthy baby, born with the same weight as a naturally conceived baby”, added Dr. Requena.
The reduction in risk is closely linked to the transfer of a single embryo (SET), a practice that all IVI clinics currently perform, allowing doctors to drastically reduce multiple pregnancies - in fact, in the last decade this type of pregnancy has been reduced by 75% - and increase the chances of full-term pregnancy and the birth of a healthy baby.
“At IVI, 100% of the transfers we make are from a single embryo, and the twin rate is only 3%, on a par with the national rate of naturally conceived twins, which is 2.4%, according to the Centers for Disease Control and Prevention (CDC)”, said Dr. Requena.
The progressive reduction in the risk of low birth weight has coincided with important advances in reproductive medicine over the last two decades. The present findings point to important advances for the safety and success of IVF and, therefore, for the continuous improvement in the results and experience of patients who place their desire to be parents in IVI's hands.
“Babies born with our help, and thanks to SET, have a similar weight and similar term pregnancy rates to those of naturally conceived babies. In short, these figures are evidence that the gap is closing between IVF and natural conception, and this is very good news for those fighting against infertility”, concluded the specialist.