Definition - What does Embryonic Demise mean?
An early embryonic demise is a form of miscarriage. The findings of transvaginal ultrasound differentiate it from other types of miscarriages (early fetal demise, delayed miscarriage, incomplete miscarriage, and complete miscarriage). A higher chance of early embryonic demise exists in pregnancies conceived after in vitro fertilization (IVF) as compared to natural conception.
Embryonic demise is also referred to as blighted ovum or an anembryonic pregnancy
FertilitySmarts explains Embryonic Demise
A variety of terms are used for early pregnancy loss, but in the presence of following ultrasound findings, the term early embryonic demise is used when:
- Gestational sac (the first ultrasonic sign of pregnancy) has a mean diameter equal to greater than 25mm
- The absence of yolk sac or no embryo in the gestational sac
The yolk sac is the first structure that appears within the gestation sac and serves to nourish the embryo before the placenta forms. An empty yolk sac is collapsed, elongated and positioned more towards the body of the uterus rather than the fundus, which is the normal position.
Chromosomal abnormalities are the most accepted cause of miscarriages. In most cases, the faulty genes come from the rapid division of embryonic cells rather than being inherited from mother or father. An increase in maternal age and abnormalities related to the receptivity of the uterus also play a role in early pregnancy loss.
In a study conducted to assess the risk of spontaneous abortion in singleton and twin pregnancies after IVF/ICSI, the researchers found that the overall incidence of spontaneous abortion (defined as early embryonic demise + fetal demise in this study) was 21.8%. This risk reduced to 11.9% in week 11 and 2.2% in week 13 of pregnancy.
The term spontaneous abortion is also used interchangeably with embryonic demise. However, by definition, any form of miscarriage is referred to as spontaneous abortion.