Pregnant Woman Showing The Progression of Fetal Growth During Gestational Week 20

Description

Mid-sagittal section through the gravid uterus at gestational week 20 places the conceptus centrally within the amniotic cavity, with the fetus in a flexed posture and the head oriented inferiorly toward the cervix. The amniotic sac outlines a fluid-filled space separating fetal skin from the decidua and myometrium, while the placenta forms a thickened disk along the uterine wall. An umbilical cord courses from the fetal umbilicus to the placental surface, suspended within the amniotic fluid and positioned away from the uterine lining except at its placental insertion. Maternal tissues frame the scene. Clear landmarks. At 20 weeks, the relationship between placenta, membranes, and uterine wall is the teaching hinge for both normal physiology and common complications. Placental location relative to the lower uterine segment helps explain placenta previa and the sonographic emphasis on measuring the placental edge-to-internal os distance, while umbilical cord insertion patterns set the stage for discussions of marginal or velamentous insertion and vasa previa risk. The fetal size and flexed lie at this stage also match the anatomy targeted in the standard mid-trimester anatomy scan, where biometric measurements and placental evaluation occur in the same session. Use this artwork in obstetrics and gynecology courses when introducing the second trimester, placentation, and membrane anatomy, and in patient-facing education for counseling around the 20-week ultrasound and placental position findings. It also fits medical publishing needs for chapters on uterine anatomy in pregnancy, fetal development milestones, and obstetric imaging correlation. Anatomical accuracy verified by SciePro's Medical Advisory Board.