Recurrent miscarriages: when is it advisable to investigate their causes and what options exist
Losing a pregnancy is an emotionally devastating experience for any couple. When this happens again, it's common for uncertainty, fear, and many questions about the causes and the chances of achieving a successful pregnancy to arise.
The good news is that, in most cases, the prognosis is favorable. In fact, between 70% and 75% of couples with recurrent miscarriages go on to have a healthy baby , even without specific treatment. However, it is important to conduct an individualized assessment to identify any contributing factors.
Dr. Vega Cabezuelo , a specialist in Gynecology and Obstetrics at the Women's Unit of the Ruber International Hospital , explains that "although recurrent miscarriages cause great concern, most couples will eventually have a healthy child. The important thing is to carry out a proper evaluation to identify if there is a treatable cause."
What is considered a recurrent miscarriage?
Although recurrent miscarriages and implantation failure are often discussed together , they are not the same clinical entity, although part of the diagnostic study carried out in both situations is similar.
"We consider that we are talking about recurrent miscarriages when there have been two or more clinical pregnancies that end in miscarriage ," explains Dr. Vega Cabezuelo.
Miscarriage is also a relatively common occurrence. Approximately 15% of pregnancies end in pregnancy loss , making it one of the most frequent complications of pregnancy.
What factors increase the risk of having another miscarriage?
According to Dr. Vega Cabezuelo, the probability of suffering another pregnancy loss depends on several factors:
- La woman's age, since the risk increases with maternal age.
- El number of previous abortionsThe greater the number of previous losses, the greater the risk of recurrence.
- La gestational age at which the abortion occurredLater losses are a factor associated with a higher risk.
- La cause of previous abortions, when it has been identified.
- Having previously had a healthy child, considered a good prognostic factor.
"Each couple has different circumstances, so the study should always be personalized," the specialist points out.
Genetics, the main cause of early miscarriages
One of the most important messages that Dr. Vega Cabezuelo conveys is that the most frequent cause of early miscarriages is genetic.
"In abortions that occur between six and seven weeks of gestation, up to 90% present chromosomal abnormalities of the embryo," he explains.
These alterations usually appear spontaneously during embryo formation and, in most cases, are not related to hereditary diseases of the parents.
What tests can help find the cause?
The specialist points out that advances in reproductive medicine allow for a more precise study of each case.
Genetic study of abortion tissue
"Ideally, whenever possible, a genetic study should be performed on the remains of the abortion ," says Dr. Vega Cabezuelo.
This test makes it possible to know if the pregnancy loss has occurred due to a chromosomal alteration of the embryo and provides very valuable information for planning future pregnancies.
Although it is not always possible to obtain an adequate sample, when it can be done it constitutes one of the most useful diagnostic tools.
Study using maternal blood
In cases where tissue from the abortion is not available, there are newer techniques that allow the genetic material of the pregnancy to be studied through a maternal blood test.
"These new tools expand our diagnostic possibilities when it has not been possible to directly analyze the pregnancy tissue," explains the specialist.
Karyotype of both parents
Another test that is part of the study is the couple's karyotype , a chromosomal analysis whose objective is to detect possible structural alterations.
"We specifically look for chromosomal translocations, which involve an exchange of genetic material between chromosomes. They are rare, but when present they can be associated with a very high risk of miscarriage," says Dr. Vega Cabezuelo.
A personalized study to offer the best strategy
Although genetic alterations are the most frequent cause, they are not the only possible explanation. Depending on the clinical characteristics of each patient, the study may also include tests to rule out anatomical abnormalities of the uterus, endocrine diseases, immunological disorders, or coagulation disorders.
"The key is to identify those factors that we can act upon and offer each couple a completely personalized approach," concludes Dr. Vega Cabezuelo.
A diagnosis of recurrent miscarriage is often met with great anxiety. However, Dr. Vega Cabezuelo offers a message of reassurance: "We know that between 70% and 75% of couples with recurrent miscarriages will go on to have a healthy baby, even without any intervention. Even so, conducting an evaluation allows us to better understand each case and offer the best options for approaching a new pregnancy with the greatest possible safety."
At the Women's Unit of the Ruber International Hospital , the approach to recurrent miscarriages combines clinical experience, advances in reproductive genetics and comprehensive care focused on the needs of each patient and their partner.
To be continued: other causes of recurrent miscarriages
Genetic abnormalities are the most frequent cause of early miscarriages, but they are not the only possible explanation. Other factors can also influence recurrent pregnancy loss, and these are part of the specialized study conducted by the Women's Unit at Ruber International Hospital.
In the second part of this article , Dr. Vega Cabezuelo will address other possible causes of recurrent miscarriages, such as uterine abnormalities, endocrine factors, immunological diseases, coagulation disorders, and other aspects that can affect the course of a pregnancy. She will also explain which tests can diagnose these conditions and what treatment options are available in each case.