For patients with recurrent pregnancy loss
Searching for unknown causes
Since 1990, more than 500 genetic polymorphisms in more than 187 genes associated with RPL have been reported. A genetic polymorphism is a genetic mutation that occurs in more than 1% of cases. In addition to the coagulation system, genetic polymorphisms in the immune system, cytokines, the endocrine system, and the metabolic system have all been shown to be involved in RPL in this study.
Annexin A5 is abundant in the placenta and has been shown to inhibit coagulation. Four studies have shown that the frequency of this ANXA5 polymorphism is higher in patients with RPL than in healthy people. We carried out the same study and confirmed that SNP5 was high in patients. However, we found that in the next pregnancy, there was no difference at all in the birth rate between having this mutation and not having it (31). Therefore, there is no need to give heparin to patients with this mutation. There is a difference between the high frequency of a certain mutation and the benefit of treatment from examining that mutation.
As this example shows, there are many genes associated with RPL, but the impact of individual gene mutations on miscarriage is not significant. Miscarriages of unknown cause are presumed to be due to multifactorial inheritance. The effect of each gene polymorphism is small, and its examination and treatment have not been shown to increase the birth rate.
Prognosis related to the pregnancy and health of the newborn in patients with miscarriage
Patients with RPL may ask, "Will my child be born safe after so many miscarriages? The answer to this question was obtained using the JECS (2). For the first time anywhere, we found that the children of pregnant women who had experienced RPL showed no differences in the frequency of congenital anomalies, chromosomal abnormalities, and neonatal pseudophilia compared to the children of pregnant women who had never had a miscarriage. It was reaffirmed, however, that these patients had fewer boys.
Also for the first time, we found that pregnant women who experienced RPL were more likely to have placenta adhesions, intrauterine infections and thrombosis (2). They were reaffirmed to be more prone to miscarriage, stillbirth, preterm delivery, gestational hypertension, and cesarean section. There was no difference in the frequency of placenta previa, amniotic fluid overload, or early placental abruption.
- Definition of recurrent miscarriage and recurrent pregnancy loss and results of the Japan Environment and Children’s Study (JECS)
- Examination and causes of RPL
- Antiphospholipid syndrome
- Treatment of antiphospholipid syndrome
- Chromosomal translocation in either partner
- Preimplantation genetic testing for chromosomal structural rearrangement
- Congenital uterine anomaly
- Thrombotic predisposition
- Endocrine abnormality
- Fetal or embryonic aneuploidy
- Preimplantation genetic testing for aneuploidy
- Immunotherapy for unexplained recurrent miscarriage
- Drug administration for repeated miscarriages of unknown cause
- Unknown Causes
- Emotional support