High-risk pregnancy encompasses maternal conditions and pregnancy complications that threaten the health of the mother, fetus, or both, requiring enhanced surveillance, specialized management, and often hospitalization. Placenta previa (placental implantation over or near the internal cervical os) causes painless bright red vaginal bleeding, typically in the second or third trimester — digital vaginal examination is absolutely contraindicated as it may provoke life-threatening hemorrhage. Placental abruption (premature separation of a normally implanted placenta) presents with painful dark vaginal bleeding, uterine rigidity, and fetal distress — risk factors include hypertension, cocaine use, trauma, and prior abruption. HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets) is a severe variant of preeclampsia with significant maternal morbidity including hepatic rupture, DIC, and renal failure — presenting with right upper quadrant or epigastric pain, nausea, vomiting, and malaise that may be misdiagnosed as gallbladder disease or viral illness. Gestational diabetes, affecting 2-10% of pregnancies, results from placental hormone-induced insulin resistance that exceeds beta-cell compensatory capacity.