Pregnancy Loss
Pregnancy losses include early pregnancy losses or miscarriages during the first 24 weeks of gestation. First-trimester pregnancy losses are the most common form of pregnancy loss, and most occur before 8 weeks of gestation. The two main factors influencing clinical pregnancy loss rates are maternal age and prior pregnancy loss. At least 50% of clinically recognized early pregnancy losses are associated with a chromosomal abnormality. Patients with antiphospholipid syndrome, unbalanced structural chromosome rearrangement, poorly controlled diabetes mellitus, and exposure to radiation, antineoplastic agents, air pollution, or cigarette smoke; those who consume alcohol; and patients with a subseptate uterus are at increased risk for early pregnancy loss. Yet there is little evidence supporting an association with luteal phase defects, thyroid dysfunction, intrauterine adhesions, uterine fibroids, infection, and inherited thrombophilias. Most patients with a history of recurrent pregnancy loss will go on to have a live birth, but these individuals are at increased risk of preterm birth, fetal growth restriction, placental abruption, and stillbirth. Recurrent pregnancy loss is also associated with cardiometabolic disease in later life, including diabetes, hyperlipidemia, hypertension, and a fivefold higher risk of myocardial infarction.
