A Pregnant Woman Showing The Gestational Stage of Pregnancy at Week Thirteen

Description

Centered within a sagittal cutaway of the maternal pelvis, the gravid uterus occupies the midline, its thick myometrium surrounding the distended uterine cavity and gestational sac. Inside, the conceptus at gestational week 13 lies in flexion, with a proportionally large head positioned superiorly and the developing limbs folded anteriorly toward the trunk. A pale umbilical cord courses from the fetal abdomen to the placenta, which is apposed to the uterine wall and separated from the fetus by the amniotic cavity. Week 13 marks the transition into the second trimester, when the uterus has expanded beyond the true pelvis and the fetus is increasingly assessed as a fetus rather than an embryo in clinical language. This view supports teaching of placental and cord anatomy in context, including how chorionic villi interface with the decidua basalis and why abnormal implantation can have consequences later, such as placenta previa or accreta spectrum disorders. The cord and placental relationship shown here also frames early discussions of hematogenous exposure, including how maternal infections or teratogens can reach the fetus through the uteroplacental circulation. Clear landmarks. Use this asset in embryology and obstetrics teaching materials when you need a single image that connects uterine anatomy to first-trimester development, or in patient-facing education explaining where the pregnancy sits and what structures support fetal growth at 13 weeks. It also fits editorial layouts on early prenatal screening, dating, and placentation for journals, textbooks, and institutional websites. Anatomical accuracy verified by SciePro's Medical Advisory Board.