If the ultrasound date is within seven days of your LMP date, we would stick with your LMP date.Ultrasounds done later in the pregnancy are less accurate for dating, so if your due date is set in the first trimester, it shouldn't be changed.THIS INFORMATION IS NOT INTENDED TO REPLACE CLINICAL JUDGMENT OR GUIDE INDIVIDUAL PATIENT CARE IN ANY MANNER. Medscape's clinical reference is the most authoritative and accessible point-of-care medical reference for physicians and healthcare professionals, available online and via all major mobile devices. The clinical information represents the expertise and practical knowledge of top physicians and pharmacists from leading academic medical centers in the United States and worldwide.The topics provided are comprehensive and span more than 30 medical specialties, covering: Diseases and Conditions More than 6000 evidence-based and physician-reviewed disease and condition articles are organized to rapidly and comprehensively answer clinical questions and to provide in-depth information in support of diagnosis, treatment, and other clinical decision-making.Because few women know the exact day they ovulated or conceived, an ultrasound done in the first trimester of pregnancy has been shown to the be the most accurate way to date a pregnancy.
"And knowing how far along you are makes it easier for your obstetrician to see that your baby is growing properly," explains ob-gyn Joanne Stone, M.They can also facilitate physician-patient discussions. Drug Monographs More than 7100 monographs are provided for prescription and over-the-counter drugs, as well as for corresponding brand-name drugs, herbals, and supplements. Drug Interaction Checker Our Drug Interaction Checker provides rapid access to tens of thousands of interactions between brand and generic drugs, over-the-counter drugs, and supplements.Check mild interactions to serious contraindications for up to 30 drugs, herbals, and supplements at a time.Another method is by adding 9 months and 7 days to the first day of the last menstrual period.Naegele's rule is named after Franz Karl Naegele (1778–1851), the German obstetrician who devised the rule.