 The occurrence of a spontaneous fetal loss FL is a rather frequent event: it has been estimated that up to 15 of pregnancies result in a fetal loss. However, recurrent events, defined as 2 or 3 loss, depending on the guidelines used American College of Obstetricians and Gynecologists or Royal College of Obstetricians Gynaecologists guidelines, occur in 1 of all pregnancies and it is noteworthy that Recurrent Fetal Loss RFL in about 30-40 of cases remain unexplained after standard gynaecological, hormonal and karyotype investigations. Furthermore, it is important to consider that chromosomal abnormalities are responsible for at least 60 of FL in the first trimester, thus an abnormal karyotype in the fetus should be excluded prior to consider testing women for genetic susceptibility to placental vascular complications inherited thrombophilia. 