The effects of intimate partner violence (IPV) on maternal and neonatal outcomes are multifaceted and largely preventable. During pregnancy, there are many opportunities within the current health care system for screening and early intervention during routine prenatal care or during episodic care in a hospital setting. This article describes the effects of IPV on maternal health (e.g., insufficient or inconsistent prenatal care, poor nutrition, inadequate weight gain, substance use, increased prevalence of depression), as well as adverse neonatal outcomes (e.g., low birth weight [LBW]), preterm birth [PTB], and small for gestational age [SGA]) and maternal and neonatal death. Discussion of the mechanisms of action are explored and include: maternal engagement in health behaviors that are considered "risky," including smoking and alcohol and substance use, and new evidence regarding the alteration of the hypothalamic-pituitary-adrenal axis and resulting changes in hormones that may affect LBW and SGA infants and PTB. Clinical recommendations include a commitment for routine screening of IPV in all pregnant women who present for care using validated screening instruments. In addition, the provision of readily accessible prenatal care and the development of a trusting patient-provider relationship are first steps in addressing the problem of IPV in pregnancy. Early trials of targeted interventions such as a nurse-led home visitation program and the Domestic Violence Enhanced Home Visitation Program show promising results. Brief psychobehavioral interventions are also being explored. The approach of universal screening, patient engagement in prenatal care, and targeted individualized interventions has the ability to reduce the adverse effects of IPV and highlight the importance of this complex social disorder as a top priority in maternal and neonatal health.