Recurrent second trimester miscarriage.

Understanding the aetiology of a second trimester miscarriage allows the obstetrician to assess the recurrence risk in the next pregnancy and guides future management. Causes include anatomical abnormalities, cervical incompetence, genital tract infection, multiple pregnancy, auto-immune factors, vaginal bleeding, and fetal abnormalities. Transvaginal ultrasound of the cervix in pregnancy may have a role in the diagnosis of cervical incompetence. There is an association between genital tract infection and second trimester miscarriage, but the value of antibiotics in the prevention of miscarriage is still to be defined.