Physiological Changes During Pregnancy

Physiological Changes During Pregnancy

• Increased Estrogen and Progesterone cause uterine enlargement, increased vascularity, hyperplasia, and hypertrophy.
• Uterine Enlargement: Length increases from 6.5 cm to 32 cm, width from 4 cm to 24 cm, and weight from 50 gm to 1000 gm at 40 weeks.
• Fundal Height: Increases with progressive enlargement of the uterus.
• Prodromal (Pre-Labor) Stage:
  • Uterine Shelfing: Fundus falls forward, making the abdomen look like a shelf when standing due to fetal head engagement.
  • Lightening: Relief of upper abdominal pressure symptoms (dyspnea and palpitation) due to descent of the uterus.
• Cervix:
  • Mucus Gland: Enlarged and secretes mucus forming a plug (operculum) that is expelled during labor.
  • Vascularity and Softening: Increases in response to estrogen and progesterone.
  • Effacement and Dilation: Cervix shortens and opens to 10 cm during labor, allowing for fetal passage.
• Vagina:
  • Muscle Thickening: Thickens and becomes more elastic for dilation during labor.
  • Length Increase: Anterior wall lengthens.
  • Vascularization and Softening: Increases due to estrogen and progesterone.
  • Leukorrhea: Thick white vaginal discharge occurs due to hormonal changes.
  • pH: Lower vaginal pH is acidic (4-6.5) compared to non-pregnant women (3.5-4.5).

Cardiovascular System

• Cardiac Output: Increases by 30-50%, peaking at 28-32 weeks.
• Blood Pressure: Slightly decreases in the second trimester.
• Supine Hypotension (Pregnancy Hypotensive Syndrome): Occurs in 3-11% of pregnant women.
  • Cause: The uterus puts pressure on the inferior vena cava (IVC) when lying on the back, reducing blood flow to the heart and uterus.
  • Symptoms: Dizziness, lightheadedness, shortness of breath.
  • Prevention: Lying on the side relieves pressure on the IVC.

Respiratory System

• Chest Size: Increases.
• Diaphragm: Moves upward.
• Hyperventilation Syndrome: Pregnant women breathe faster and deeper than usual.
• Oxygen Consumption: Increases by 14-20%.
• Tidal Volume: Increases by 30-40% to meet increased oxygen demand.

Urinary System

• Kidney Length and Volume: Increase during pregnancy and decrease postpartum.
• Micturition Frequency: Increases, especially in the first and third trimesters, due to uterine pressure on the bladder.
• Urinary Tract Infections: More likely due to urinary stasis.

Gastrointestinal Tract

• Morning Sickness and Vomiting: Common in early pregnancy.
• Indigestion: A common discomfort.
• Constipation: Caused by pressure on the intestines, relaxation of smooth muscles by relaxin, and sedentary habits.
• Hemorrhoids: Can develop due to increased pressure in the pelvic region.

Nervous System

• Mood Liability: Sleepiness, depression or excitement and insomnia can occur.
• Neuropraxia: Nerve compression due to water retention, leading to conditions like carpal tunnel syndrome.
• Pregnancy Cravings: Commonly experience.

Cutaneous System

• Pigmentations: Develop due to hormonal changes:
  • Linea Nigra: A dark line appearing between the umbilicus and symphysis pubis.
  • Darkening Areolas: The primary areola becomes darker and secondary areola appear.
  • Cloasma Gravidarum (Mask of Pregnancy): Butterfly-shaped pigmentation on the forehead, nose, upper lip, and cheeks.
• Striae Gravidarum (Stretch Marks): Red streaks appear due to skin stretching and rupture of elastic fibers.
  • Striae Albicantes: Pale white streaks develop after labor due to fibrosis.

Metabolic and Endocrine Changes

• Relaxin: Hormone secreted by the corpus luteum in the ovary, important for joint relaxation and uterine growth.
• Estrogen, Progesterone, and Human Placental Lactogen: Have significant effects on the body during pregnancy.

Musculoskeletal System

• Abdominal Muscles: Stretched to their limit.
• Ligaments: Softening and increased mobility due to relaxin, leading to increased risk of joint injury.
• Pelvic Floor Muscles: Drop by 2.5 cm due to uterine weight.
• Postural Changes: Forward head, rounded shoulder, increased lumbar lordosis, hyperextended knees, and pronated feet.
  • Impact: Changes in balance.
• Muscle Changes: Shortened hip flexors, lower back and pectoral muscles, and elongated abdominal, neck, and upper back muscles.
• Waddling Gait: Due to lax ligaments and pelvic joint instability.

Antenatal Period and Care

• Antenatal Period: The time during pregnancy.
• Antenatal Care: Systemic medical supervision during pregnancy to ensure a healthy pregnancy and labor.
  • Components: Medical, psychological, and physical care.

Antenatal Care Team

• Obstetrician: Provides medical care.
• Dietitian: Provides nutritional guidance.
• Physiotherapist: Provides physical therapy and guidance for exercise.
• Psychologist: Provides emotional and mental support.
• Pediatrician: Provides care for the newborn.

Medical Antenatal Care

• First Visit: Includes taking medical history, physical examination, urine and blood tests.
• Return Visits: Include monitoring symptoms, weight, edema, blood pressure, and performing abdominal examinations and urine tests

Physical Antenatal Care

• Role of Physiotherapy:
  • Educate: On safe exercise, posture, and body mechanics.
  • Treat: Concerns such as low back pain, pelvic pain, and muscle cramps.
  • Help: Women prepare for labor and delivery.
  • Provide: Pain relief techniques.
  • Teach: Positions to facilitate labor.

Physical Antenatal Care (Specific Interventions)

• Pelvic Support: To reduce pubic pain from diastasis of rectus abdominis.
• Lumbar Pain Relief: Soft tissue techniques and mobilization.
• Cramp Relief: Sustained stretching and foot exercises.
• Relaxation Techniques: Reduce stress, pain, and promote energy conservation during labor.
• Breathing Awareness: Promote relaxation and manage pain during labor.

General Role of Physiotherapists

• Electrotherapy should not be used over the pregnant abdomen.

Low Back Pain Treatment

• Ice Application (25 Minutes): Reduces swelling, nerve conduction velocity, and increases endorphins and enkephalins.
  • Methods: Ice cube massage (directly on skin) and ice packs.

Explore the significant physiological changes that occur during pregnancy, including the effects of hormones like estrogen and progesterone. This quiz covers uterine enlargement, changes in the cervix, and developmental stages leading to labor. Test your understanding of these essential concepts in prenatal physiology.