New insights into mechanisms behind miscarriage

Abstract

Sporadic miscarriage is the most common complication of early pregnancy. Two or three consecutive pregnancy losses is a less common phenomenon, and this is considered a distinct disease entity. Sporadic miscarriages are considered to primarily represent failure of abnormal embryos to progress to viability. Recurrent miscarriage is thought to have multiple etiologies, including parental chromosomal anomalies, maternal thrombophilic disorders, immune dysfunction and various endocrine disturbances. However, none of these conditions is specific to recurrent miscarriage or always associated with repeated early pregnancy loss. In recent years, new theories about the mechanisms behind sporadic and recurrent miscarriage have emerged. Epidemiological and genetic studies suggest a multifactorial background where immunological dysregulation in pregnancy may play a role, as well as lifestyle factors and changes in sperm DNA integrity. Recent experimental evidence has led to the concept that the decidualized endometrium acts as biosensor of embryo quality, which if disrupted, may lead to implantation of embryos destined to miscarry. These new insights into the mechanisms behind miscarriage offer the prospect of novel effective interventions that may prevent this distressing condition.

The role of immunological markers in assessment of implantation uterus receptivity - clinical implications.

“…Oznacza to, iż kobiety z nieprawidłową funkcją endometrium mogą pozornie wydawać się bardzo płodne, jednak w rzeczywistości dochodzi u nich do opóźnionej, w stosunku do zdrowych kobiet, eliminacji nieprawidłowych zarodków, kiedy to ciąża jest już klinicznie stwierdzona. Czas osiągania kolejnej ciąży jest przez te kobiety wprawdzie krótki, ale liczba późniejszych poronień wysoka [4,8].…”

Recurrent Miscarriage: A Review

“…Clinical miscarriages may be subdivided into early clinical pregnancy losses (before gestational week 12) and late clinical pregnancy losses (gestational weeks 12 to 21). The term miscarriage is preferred rather than abortion both by patients and physicians, although "spontaneous abortion" is still used in scientific literature [3,4].For more than 30 years, controversy has existed on the number of miscarriages required to define RM and when diagnostic testing is warranted [5] …”

“…The term miscarriage is preferred rather than abortion both by patients and physicians, although "spontaneous abortion" is still used in scientific literature [3,4].…”

“…In women older than 40 years of age, the sporadic miscarriage rate approaches 50%. Late losses between 12 and 22 weeks occur less frequently and constitute around 4% of pregnancy outcomes [4,9].Compared to sporadic miscarriage the prevalence of RM is considerably lower irrespective of whether biochemical losses are included or not. Approximately 1% of all women trying to conceive have recurrent miscarriage, defined as three previous miscarriages; when recurrent miscarriage is defined as two previous miscarriages, the proportion rises to 3% [12,13].…”

“…The definition ranges from two clinical miscarriages, not necessarily consecutive, according to the American Society for Reproductive Medicine (ASRM) [6] and a joint International Committee for Monitoring Assisted Reproductive Technology and World Health Organization glossary [7], affecting more than 3% of couples desiring a baby to three consecutive pregnancy losses (not necessarily intra-uterine) as defined by both the European Society for Human Reproduction and Embryology and the Royal College of Obstetricians and Gynecologists [4] and affecting 1% of couples trying to conceive [8].…”