Recurrent Miscarriages
Recurrent Miscarriages
What Are Recurrent Miscarriages?
Recurrent miscarriages (also called repeated miscarriages) are defined as three or more consecutive spontaneous miscarriages of clinically recognised pregnancies.
Classification Of Recurrent Miscarriages
Recurrent miscarriages are classified into two types: primary and secondary.
- Primary Recurrent Miscarriages
This term refers to women who have had three or more consecutive spontaneous miscarriages with the same partner, and without any pregnancy progressing beyond the 24th week of gestation.
- Secondary Recurrent Miscarriages
This term refers to women who have had three consecutive spontaneous miscarriages with the same partner, occurring either after the birth of a child or after an intrauterine fetal death beyond the 24th week of gestation.
The first category is more common than the second, as 80% of couples with recurrent miscarriages belong to the first category and the remaining 20% to the second.
What Causes Recurrent Miscarriages?
The causes of recurrent miscarriages are multifactorial and include various contributing factors.
- Genetic Causes
Chromosomal abnormalities, while the most common cause of sporadic miscarriages, occur less frequently in women with recurrent miscarriages. Couples in this category may require genetic counselling.
- Endocrine Causes
Hormonal disorders only rarely contribute to recurrent miscarriages. More commonly, poorly controlled diabetes mellitus may lead to miscarriage, while less commonly disorders of prolactin and the thyroid may be implicated.
- Thrombophilia (Inherited Or Acquired)
A tendency for the mother’s blood to clot more easily—whether due to inherited thrombophilia, acquired thrombophilia, or a combination—can often underlie recurrent miscarriages. Thrombophilia is diagnosed through specialised blood tests.
Anatomical Abnormalities Of The Uterus
These include congenital or acquired uterine abnormalities such as a uterine septum, bicornuate uterus, submucosal fibroids, endometrial polyps, endometrial adhesions, etc. In this category, it is also appropriate to mention cervical insufficiency, which is often due to previous surgical procedures and is treated with cervical cerclage at the end of the first trimester.
Immunological Causes
When the pregnancy is recognised as “foreign” by the mother and her body does not protect it but instead rejects it. Identifying these causes is done through blood tests and specialised evaluation of the expelled tissue. This theory has weakened in recent years, as studies have not confirmed this miscarriage mechanism.
Infections
The role of infections (toxoplasmosis, cytomegalovirus, gonococcus, rubella, mycoplasma, chlamydia) as a possible cause of recurrent miscarriages has not yet been clarified, as they have been associated more with isolated miscarriages rather than recurrent miscarriages.
Unknown Causes
In a significant proportion of cases (20–30%), the cause of recurrent miscarriages remains unexplained. It is worth noting that environmental factors such as smoking, excessive caffeine and alcohol intake, severe stress, certain chronic conditions, and substance misuse have at times been linked to recurrent miscarriages.
For more information about recurrent miscarriage, please contact the experienced obstetrician–gynaecological surgeon Dr Dimitris Koleskas, MRCOG, fertility specialist, and schedule your appointment. With more than 20 years of experience and a strong scientific background, Dr Koleskas provides high-level medical guidance and care in the field of obstetrics and gynaecology.
