Mid-trimester pregnancy loss.

Mid-trimester pregnancy loss (MTL) occurs between 12 and 24 weeks' gestation. The true incidence of this pregnancy complication is unknown, because research into MTL in isolation is scarce, although the estimated incidence has been noted to be 2% to 3% of pregnancies. A comprehensive preconceptual screening protocol is recommended, because the cause for an MTL may be present in isolation or combined (dual pathology), and is often heterogeneous. Patients with a history of MTL are at an increased risk of future miscarriage and preterm delivery. This risk is increased further depending on the number of associative factors diagnosed.