Definition. Expulsion or removal of an embryo or fetus from the uterus before it is capable of independent survival.
Of all conceptions 50–75% abort spontaneously. Most are unrecognized because they occur before or at the time of the next expected menses.

Spontaneous miscarriage

Definition. Loss of a clinically recognized pregnancy before 20 weeks’ gestation or <500 g.
Make up 15–20% of clinically diagnosed pregnancies.
Risk factors include advanced maternal age, increasing gravidity, prior miscarriage, and smoking.
History. Vaginal bleeding is the most common presenting complaint, followed by crampy abdominal pain.
Examination. Initially, vital signs should be taken to rule out hemodynamic instability. Speculum examination allows visualization of the cervix and potentially the location of products of conception. Bimanual examination may help estimate gestational age.
Laboratory tests. Serum human choronic gonadotropin (hCG), blood count, and rhesus (Rh) typing should be sent (virtually all Rh-negative patients should receive anti-D immunoglobulin prophylaxis [see Chapter 53]).

Etiology (see also Chapter 24)

More than 80% of all miscarriages occur in the first trimester (<12 weeks’ gestation). The exact mechanisms are not always apparent, but death of the embryo or fetus nearly always precedes spontaneous expulsion. As a result, finding the cause of early miscarriage involves ascertaining the cause of fetal death. At least half result from chromosomal abnormalities.
Less than 20% of all miscarriages occur in the second trimester (12–20 weeks’ gestation). The fetus frequently does not die before expulsion and anatomic factors are more likely to be causative.

Jun 6, 2016 | Posted by admin in GYNECOLOGY | Comments Off