What is spontaneous abortion?

➢ Spontaneous abortion, or “miscarriage,” is defined as pregnancy loss before 20 weeks of gestation. ➢ Most of these occur before 12 weeks. ➢ 10 to 15% of clinically recognized pregnancies terminate in spontaneous abortion. ➢ Multiple fetal and maternal causes of spontaneous abortion have been identified: • Fetal chromosomal anomalies: aneuploidy,polyploidy, and translocations, are present in approximately 50% of early abortuses. • Maternal endocrine factors: luteal-phase defect, poorly controlled diabetes, and other uncorrected endocrine disorders • Physical defects of the uterus: submucosal leiomyomas, uterine polyps, or uterine malformations, may prevent or disrupt implantation • Systemic disorders affecting the maternal vasculature: antiphospholipid antibody syndrome, coagulopathies, and hypertension • Infections with protozoa (Toxoplasma), bacteria (Mycoplasma, Listeria), or a number of viruses Ascending infection is particularly common in second trimester losses