Human Fetus at 40 Weeks in the Womb (Brown Skin)

Description

At 40 weeks of gestation the fetus fills nearly the whole uterine cavity, shown here curled in the classic flexed attitude with the head down in cephalic presentation, chin toward the chest, arms folded across the trunk and the hips and knees drawn up. Surface detail is that of a term newborn: scalp hair, a well-formed auricle, closed eyelids, plump subcutaneous fat over the limbs and abdomen, and separated fingers and toes with formed nails. The translucent amniotic sac encloses a now-reduced volume of amniotic fluid, and the coiled umbilical cord, with its paired arteries and single vein, passes from the abdominal insertion between the lower limbs toward the placental surface. The surrounding myometrium of the uterine wall is rendered as a thick vascular envelope closely applied to the membranes. Term anatomy of this kind underpins obstetric assessment in the final weeks. Presentation, lie and attitude determine the mechanism of labour and are established clinically by Leopold manoeuvres and confirmed on ultrasound; the flexed vertex shown here presents the smallest suboccipitobregmatic diameter to the pelvic inlet. Fluid volume, cord position and estimated fetal weight guide decisions on induction, expectant management or caesarean delivery, and the same image supports discussion of cord entanglement, oligohydramnios and the assessment of fetal wellbeing by biophysical profile or cardiotocography. The illustration suits obstetric and midwifery teaching on fetal presentation and the stages of labour, antenatal class handouts, and patient-facing material prepared by maternity units and clinics. It also serves as a closing figure in gestational timeline series for textbooks, mobile pregnancy applications and editorial features on term birth. Anatomical accuracy verified by SciePro's Medical Advisory Board.