Chapter 4: Physiological and Psychosocial Changes During Pregnancy

Pregnancy triggers extensive cardiovascular adaptations including substantial increases in cardiac output and blood volume to supply the developing fetus, often resulting in a physiological anemia requiring iron supplementation. The reproductive system undergoes dramatic structural changes as the uterus expands from its non-pregnant state, accompanied by cervical modifications such as increased vascularity and softening, mucus plug formation, and augmented vaginal secretions. The respiratory system increases tidal volume significantly while progesterone-mediated smooth muscle relaxation occurs, frequently causing dyspnea despite enhanced oxygen delivery. Gastrointestinal complications emerge from hormonal influences, including nausea in early pregnancy, heartburn from esophageal sphincter relaxation, and constipation from reduced intestinal motility. Renal adaptations involve enlarged kidneys with heightened filtration rates, though urinary frequency and infection risk increase due to anatomical compression and ureter relaxation. Integumentary and musculoskeletal changes manifest as hyperpigmentation patterns, stretch mark formation, postural shifts causing lumbar lordosis, and potential nerve compression syndromes. The chapter details pregnancy confirmation through a hierarchy of signs ranging from subjective presumptive indicators to objective probable findings and definitive positive signs, with dating accomplished through Naegele's rule applied to the last menstrual period. Psychosocial dimensions address maternal emotional tasks including pregnancy acceptance and preparation for parenthood, paternal adaptation phases moving from announcement through focusing, and critical perinatal mental health considerations. The chapter emphasizes the necessity of screening for intimate partner violence and psychological distress using trauma-informed approaches, recognizing that pregnancy represents a vulnerable period requiring comprehensive assessment of maternal safety and wellbeing across physical, emotional, and social dimensions.