Pregnant Woman at Week 20 of Gestation, Lateral View (Asian Skin)

Description

Seen from the side, the maternal torso is rendered semi-transparent so that the gravid uterus and its contents stand out against the abdominal wall and bony pelvis. The fetus at approximately 20 weeks of gestation lies in a flexed attitude within the amniotic sac, head directed inferiorly toward the pelvic inlet, with the umbilical cord looping anteriorly from the abdomen to the placental disc on the uterine wall. The uterine fundus has risen to about the level of the umbilicus, displacing loops of small intestine superiorly and posteriorly. Behind and below, the urinary bladder sits anterior to the cervix and vagina, the rectum lies against the sacrum, and the lumbar vertebrae, sacrum and pubic symphysis frame the pelvic cavity. The midpoint of pregnancy is the reference stage for obstetric assessment: fundal height at the umbilicus, quickening, and the detailed mid-trimester anomaly ultrasound in which fetal biometry, cardiac outflow tracts, spine and placental site are surveyed. This lateral perspective demonstrates why bladder capacity falls and why lumbar lordosis increases as the uterus enlarges and the maternal centre of gravity shifts, both common sources of urinary frequency and low back pain. The spatial relation of the placenta to the internal cervical os shown here is the anatomical basis for assessing placenta praevia. The illustration suits antenatal education leaflets, midwifery and obstetric nursing curricula, and embryology or human development lectures that follow gestation week by week. Publishers of pregnancy handbooks, ultrasound training material and app-based week-by-week trackers can use it alongside the other stages of this series to show progressive uterine growth in a consistent lateral orientation. Anatomical accuracy verified by SciePro's Medical Advisory Board.