Although it is thought that about 15-20% of pregnancies result in a miscarriage, the ratio is expected higher since women may not perceive early miscarriage or they may unconsciously address their miscarriage as a negligible deviation in their menstrual period. There are different reasons behind miscarriages such as choromosomal, hormonal, anatomical, auto immunological and exogenous (external).
Fetal chromosomal abnormalities thought to be one of the most important causes for about 50-60% of first trimester (first three months), 20-25% of second trimester and 5-10% of third trimester miscarriages. These anomalies detected in the fetus are usually nascent and risk of recurrence is very low in other pregnancies.
Even if both parents are healthy; some chromosomal disorders, causing miscarriage, might still be detected. Therefore, chromosomal analysis is required for both miscarriage materials carrying fetal tissue cells and blood samples taken from couples who have experienced 2 or more consecutive miscarriages. Unless chromosomal abnormalities causing miscarriage are detected at the end of genetic investigation, other possibilities for miscarriage should be evaluated by an obstetrician.
In contrast to other materials taken for genetic analysis (peripheral blood, umbilical cord blood, amniotic fluid and chorionic villi) , miscarriage material shows some differences. If there is no any alive tissue in the sample taken, it is a challenging issue and may block a feasible work on it. Furthermore, during removal of miscarriage material, it may contact with external environment resulting in reproduction of microorganisms in some samples. Due to such risks factors, mission may not be completed.