Roberto Jose Romero-Galue, D(Med)Sc,M.D.

The Pregnancy Research Branch studies pregnancy and its complications, with a focus on the leading causes of maternal and infant death (e.g. prematurity, infection, fetal death). Its emphasis is on diagnosis, treatment, prediction, and prevention. This research is guided by the concept of "the Great Obstetrical Syndromes": pregnancy complications have multiple etiologies, and patients with the same clinical diagnosis may have different underlying pathologic processes. Understanding those processes is essential to identify who is at risk and determine which interventions are effective.

1. Causes of spontaneous preterm labor and delivery: spontaneous preterm labor can arise through different pathologic processes, including intrauterine infection, sterile intraamniotic inflammation, an untimely decline in progesterone action, vascular disorders, and maternal antifetal rejection. The Branch studies these mechanisms to improve the diagnosis and treatment of spontaneous preterm labor; 2. Prediction and prevention of preterm birth: the Branch showed that sonographic measurement of cervical length in the midtrimester can identify patients at risk weeks or months before the onset of spontaneous preterm labor. In an international randomized clinical trial, vaginal progesterone reduced the risk of delivery before 33 weeks by approximately 40% in patients with a short cervix. Several economic analyses have found that routine cervical length screening, followed by treatment of patients with a short cervix, is cost-effective. Earlier U.S. models projected potential health care savings of approximately $500 million annually; 3. Intrauterine infection and fetal injury: we have established the role of intrauterine infection and inflammation in spontaneous preterm birth and fetal injury. It introduced the concept of the fetal inflammatory response syndrome and investigated the association between inflammation before birth and later neurologic injury, including cerebral palsy. This work has also led to methods for the rapid diagnosis of intraamniotic infection and inflammation; 4. Amniotic fluid embolism: this is a catastrophic and frequently lethal complication of pregnancy which is unpredictable and non-preventable. We have proposed a new paradigm in which a subclinical cytokine storm may precede, and contribute to, the clinical event in a subset of patients. This possibility is being investigated as a path toward prediction and prevention; 5. Congenital anomalies: the Branch has advanced the prenatal diagnosis of congenital anomalies through ultrasound and magnetic resonance imaging, particularly in the assessment of fetal anatomy and the detection of congenital heart defects. Dr. Romero and colleagues also introduced fetoscopic surgery to treat selected fetal conditions, including twin reversed arterial perfusion sequence; 6. Fetal death: we investigates the causes and mechanisms of fetal death, including deaths that remain unexplained after clinical evaluation. It has also studied maternal blood biomarkers that to identify pregnancies at risk before fetal death occurs. A patented biomarker can identify 80% of unexplained fetal death in late pregnancy. We use large scale proteomic to identify additional biomarkers and improve the prediction of fetal death; 7. Term parturition, labor progress, and cesarean delivery: we studied the physiology of parturition at term and have developed methods to characterize how labor progresses. We used single-cell transcriptomics, proteomics, lipidomics, and other high-dimensional approaches to investigate the biological changes associated with labor. The Branch also focuses how to make cesarean delivery safer, including how best to close the uterine incision to promote healing and reduce complications.

Dr. Roberto Romero is Chief of the Pregnancy Research Branch at NICHD/NIH. He trained in obstetrics and gynecology and maternal-fetal medicine at Yale University, joined the faculty, and became Director of Perinatal Research. He subsequently joined NIH to found the Perinatology Research Branch, established by Public Law to study pregnancy and its complications and now known as the Pregnancy Research Branch.

Dr. Romero and his team have made contributions to: 1) the early diagnosis and treatment of ectopic pregnancy; 2) the prenatal diagnosis of congenital anomalies and fetoscopic treatment of selected fetal conditions; 3) the characterization of fetal anatomy, biometry, growth, physiology, and pathology through ultrasound and magnetic resonance imaging; 4) the prediction and prevention of spontaneous preterm birth through sonographic assessment of cervical length and vaginal progesterone treatment; 5) the study of amniotic fluid embolism, preeclampsia, and clinical chorioamnionitis; and 6) the investigation of fetal death and maternal blood biomarkers that may identify pregnancies at risk before fetal death occurs. Dr. Romero introduced the concept of the Great Obstetrical Syndromes to explain why a clinical diagnosis can arise from different pathologic processes, often with a long preclinical phase and effects on both the mother and fetus. This framework has informed research into the diagnosis, prediction, treatment, and prevention of complications of pregnancy. He also introduced the concept of the fetal inflammatory response syndrome and advanced methods for the rapid diagnosis of intraamniotic infection and inflammation. An elected member of the National Academy of Medicine, Dr. Romero has authored more than 1,300 peer-reviewed publications. As of September 2026, his work has received 198,886 citations, with an h-index of 208. His research has generated multiple patents, and he maintains active collaborations within NIH and with academic institutions. He is among the four highest-ranked physician-scientists across NIH by scholarly impact. He serves as Editor-in-Chief for Obstetrics of the American Journal of Obstetrics & Gynecology, the specialty’s oldest journal, founded more than 150 years ago. His contributions have been recognized with national and international awards and honorary doctorates from universities around the world.