The Guest Editors have assembled expert authors to provide current clinical views and recommendations for patients with medical disorders in pregnancy. Clinical reviews are devoted to the following topics: Obstructive sleep apnea in pregnancy; Pregestational Diabetes; Gestational Diabetes; Maternal mortality in the 21 century; Infections in pregnancy and the role of vaccines; Peripartum cardiomyopathy; Update on HIV in pregnancy: Thromboprophylaxis; Opiate abuse in pregnancy.