Recurrent miscarriage (RSA) is a common complication of pregnancy. There are many patients, both in outpatient clinics and online consultations. In addition to the currently known causes, the cause is still unknown in at least 40% of patients in clinical practice. Therefore, there are many couples trapped in a situation of normal tests and still miscarriage. As a result, patients with recurrent miscarriages can be expected to feel anxious, confused and torn. As a supplement to my previous article, I would like to answer the questions that are often asked by patients in the clinic. There is always one that you want to know.
1. What is recurrent miscarriage?
Three or more consecutive spontaneous miscarriages before 28 weeks of gestation are called recurrent miscarriages (RSA) or habitual miscarriages. Strictly speaking, recurrent miscarriage refers to 3 or more consecutive spontaneous abortions with the same sexual partner.
Those that occur before 12 weeks of pregnancy are called early recurrent abortions (ERSA) and those that occur between 12 and 28 weeks of pregnancy are called late recurrent abortions (LRSA). Most recurrent miscarriages are early miscarriages.
The incidence of recurrent miscarriage is about 1-5% of all pregnancies. Spontaneous abortion is sometimes referred to as embryonic arrest in the description of clinical symptoms or in ultrasound diagnosis.
2. What is a biochemical pregnancy? Is a biochemical pregnancy considered a spontaneous abortion?
Biochemical pregnancy is relative to clinical pregnancy. It is an early miscarriage that occurs within 5 weeks of gestation, with a detectable elevation of HCG in the blood or a positive urine pregnancy test, but the gestational sac is not visible on ultrasound, suggesting a failure of fertilization of the egg.
If a gestational sac is seen in the uterus on ultrasound, it is called a clinical pregnancy.
Some people call a biochemical pregnancy a “subclinical miscarriage”. However, there is no clear-cut definition of a biochemical pregnancy as a spontaneous abortion.
3. The difference between spontaneous abortion and induced abortion
Before 24 weeks of gestation, the purpose of ending a pregnancy is to remove the embryo and placenta from the uterus by manual means, but not yet mature.
Spontaneous abortion is defined as a pregnancy that terminates on its own before 28 weeks and the fetus weighs <1000g.
4.Should you have a checkup after one embryonic abortion?
A spontaneous abortion usually has a great chance. The success rate of a second pregnancy is as high as 80%. Therefore, from the medical or economic point of view, it is not necessary to do many tests. The onset or progression of a disease has to be repetitive in its symptoms. As I always say, a fall at a young age when you go out can only be described as carelessness; if you fall frequently, then you need to be properly investigated.
One spontaneous abortion does not mean that the next pregnancy must be bad. According to statistics, even with four spontaneous abortions, there is still more than a 50% chance of avoiding miscarriage in another pregnancy. However, in patients with such a history, proper attention for another pregnancy is still necessary. Such as proper rest, but should avoid absolute bed rest; under the guidance of the doctor to strengthen the measures to protect the fetus, and so on. Tension can affect all systems of the body, especially the neuroendocrine system, which is harmful to the development of the embryo and the maintenance of the pregnancy, and should be adjusted as well as possible.
5.What are the causes of recurrent miscarriage?
The causes of recurrent miscarriage are complex and have been identified to include genetic factors, anatomical abnormalities, infectious factors, endocrine abnormalities, pre-thrombotic states, immune factors, etc. In addition, about 50% of the cases are still related to the causes of recurrent miscarriage. In addition, there are still about 50% of unknown causes, called recurrent miscarriage of unknown origin.
6.Should I be examined if I have two spontaneous miscarriages?
In recent years, many scholars have proposed to include two consecutive spontaneous abortions into the category of recurrent miscarriage, because after two consecutive spontaneous abortions, the miscarriage rate of another pregnancy can increase significantly, and it is necessary to pay enough attention to it and intervene to avoid recurrence of miscarriage. Therefore, systematic examination should be performed when there are two spontaneous miscarriages.
7.What does the systematic examination of miscarriage include?
The examination and treatment of recurrent miscarriage mainly focus on the cause, including the following aspects:
・Coagulation test
Endocrine examination
Immunological examination
Thyroid function tests
Diabetes mellitus examination
・Check for polycystic ovary syndrome
Genetic material test Chromosome karyotype analysis of miscarried embryos
Karyotype analysis of couples
Examination of the reproductive tract: Examination of uterine malformations, examination of cervical function
Examination of infection factors
At present, there are no mandatory tests for recurrent miscarriage, and the requirements vary from hospital to hospital. Each aspect of the examination includes several tests. Therefore, patients should choose under the guidance of a doctor.
8.Does miscarriage occur even if the examination is normal?
The etiology of recurrent miscarriage is complex. In addition to the currently known causes, at least 40% of patients still have unknown clinical causes. Therefore, many couples are trapped in the situation of “normal examination but still miscarriage”.
Recent studies in reproductive immunology have shown that 50% of unexplained RSA is mainly related to abnormal immune factors. Two-thirds of them are alloimmune RSA, which is the main type of unexplained RSA.
The pathogenesis of alloimmune RSA, which refers to miscarriage caused by imbalance of immune balance between mother and fetus, is not fully understood and is an exclusive diagnosis (i.e., it can be diagnosed only after rigorous etiological screening to exclude chromosomal, anatomical, endocrine, infectious, and autoimmune factors. This is why doctors have to prescribe so many tests), and there is still a lack of specific testing indicators and no uniform treatment plan. In this regard, I always say, “Scientists are trying, we are waiting.”
Although the cause is unknown, it is definitely not incurable. Current treatment methods include active immunotherapy or passive immunotherapy with intravenous immunoglobulin infusion and Chinese medicine (tonifying the kidneys and strengthening the spleen).
For this part of the patients who are struggling with entanglement I tend to advise one thing: medical scientists have been working hard, we only have to be patient and wait. The pre-implantation aneuploidy screening (PGS) technology started in our hospital this year can be helpful for this group of patients.
What should I do if I still have a miscarriage even though the test is normal?
9. How to treat recurrent miscarriage
As mentioned above, the complexity of the etiology of recurrent miscarriage makes RSA difficult to treat and is currently a difficult area of medical research. At present, the treatment of recurrent miscarriage mainly focuses on the cause, including: anticoagulation, endocrine therapy, immunotherapy, surgical correction of reproductive tract abnormalities, and assisted reproductive technology.
For patients with unknown causes, preimplantation aneuploidy screening (PGS) should be considered. Patients can be consulted and choose carefully.
10. About “Immunotherapy”
Active immunotherapy. Active immunotherapy is a kind of immunotherapy that stimulates the mother to produce self-protective antibodies, and is a common clinical treatment for unexplained RSA. It is also commonly referred to as husband leukocyte immunotherapy and third-party leukocyte immunotherapy. It is an empirical treatment, and whether it is necessary and effective is still controversial. Although this treatment method is widely used in clinical practice, it still needs the support of a large number of multicenter and rigorous clinical trials.
11. Can abortion be solved by artificial insemination or in vitro fertilization?
No. Conventional “IVF” – often referred to as first- or second-generation in vitro fertilization – cannot solve the problem of spontaneous miscarriage or embryonic abortion.
12. I have had two (or three) miscarriages and my system tests are normal, why should I go for genetic counseling?
Please refer to — Outpatient Clinic Notes — What should I do if I still miscarried despite normal tests?
1. Common chromosomal disorders such as chromosomal number and structure abnormalities in both partners, including Roche translocations and mutually balanced translocations. Some translocations are not diagnosable, please consult your doctor after consultation.
2. Common monogenic genetic disorders. Such as thalassemia, progressive muscular dystrophy, etc.
3.Children with chromosomal disorders (such as trisomy 21) have been born, and both spouses have normal chromosomes.
4, high reproductive age of the female partner, according to ovarian function, the number of follicles can be selected for aneuploidy screening of embryos (high age may produce aneuploidy embryos, which is one of the causes of miscarriage and congenital stupidity)
5, repeated unexplained spontaneous miscarriage, unexplained embryo implantation failure (selection of aneuploidy embryos)
6, screening for genes causing adverse diseases (e.g. oncogenes, HLA matching for leukemia patients).