Maternal Adaptations to Pregnancy

Maternal Adaptations to Pregnancy

• Gravida: The number of times a client has been pregnant, including the current pregnancy.
• Para: The number of pregnancies that have reached 20 weeks gestation, regardless of outcome. Twins/triplets are counted as one.
• GTPAL: A system used to document obstetric history.
  • G: Gravida
  • T: Term births (38-42 weeks)
  • P: Preterm births (20-38 weeks)
  • A: Abortions (before 20 weeks)
  • L: Living children
• Example: A woman who has been pregnant three times, had two term births, no preterm births or abortions, and has two living children would be documented as G3 T2 P0 A0 L2.
• Primigravida: A client pregnant for the first time
• Multigravida: A client who has been pregnant more than once
• Primipara: A client who has not delivered a pregnancy past 20 weeks
• Multipara: A client who has delivered more than one pregnancy past 20 weeks

Signs of Pregnancy

• Presumptive Signs: Changes felt by the woman. Examples include amenorrhea, nausea, fatigue.
• Probable signs: Changes observed by the examiner. Examples include changes in pelvic organs or a positive HCG test
• Positive Signs: Changes that are definitively linked to the presence of a fetus. Examples include a fetal heartbeat, fetal movements, and ultrasound visualization of a fetus.

Reproductive System Changes

• Uterus:
  • Hypertrophy and hyperplasia of myometrial cells
  • Moves from being a pelvic organ to an abdominal organ
  • By pregnancy's end, approximately 1/6 of the mother's total body mass.
• Cervix:
  • Mucous plug forms
  • Increased vascularity (blood vessels) and fragility.
• Vagina:
  • Increased vascularity.
  • Tissue loosens/vault lengthens.
  • Increased secretions.
• Ovaries:
  • Stop producing ova.
  • Corpus luteum releases progesterone and estrogen until the placenta takes over.
• Breasts:
  • Placenta releases estrogen and progesterone, increasing alveoli and ductal systems.
  • Prolactin is needed for milk production, but is inhibited by estrogen & progesterone. Production of milk stops during pregnancy when the placenta produces the required hormones

Cardiovascular Changes

• Increased blood flow to the placenta, uterus & breasts
• Cardiac workload increases (increased cardiac output by 30-50%)
• Increased heart rate (by 10-15 bpm)
• Blood pressure may decrease during the first and second trimesters but returns to normal by term.
• Supine Hypotensive Syndrome: Gravid uterus compresses vena cava (especially when lying flat). Interferes with blood return to the heart—resulting in dependent edema, varicose veins, hemorrhoids, and thrombophlebitis
• Left lateral recumbent position is considered to be the best position for the expectant mother.

Hematological Changes

• Rapid increase in plasma volume (40-45% above non-pregnant levels, peaking at 32-34 weeks).
• Increased red blood cell production (RBC) (approximately 20-30% more).
• White blood cell (WBC) count increases in the 2nd trimester, peaking in the 3rd.
• Fibrin/fibrinogen and clotting factors (VII, VIII, IX, X) increase, increasing risk of thrombosis.

Respiratory Changes

• Increased oxygen requirements / lowered threshold for CO2.
• Ligaments relax, and the diaphragm is displaced, increasing chest expansion.
• Upper respiratory tract becomes more vascular with edema in the nose, pharynx, trachea and bronchi.

Renal System Changes

• Increased pressure from the uterus leads to increased urinary frequency in the first and third trimesters.
• Glomerular filtration rate (GFR) increases.
• Possible glycosuria.
• Proteinuria (trace amounts are normal; > 1 warrants close monitoring)

Integumentary System Changes

• Increased skin pigmentation (MSH) due to darkening of areola, nipples, axilla, and perianal area. This affects the complexion and creates chloasma.
• Linea nigra
• Striae gravidarum(stretch marks)
• Vascular spiders
• Palmar erythema
• Increased perspiration
• Gum hypertrophy
• Increased nail growth
• Decreased hair loss, and potential hirsutism

Musculoskeletal Changes

• Center of gravity shifts forward, leading to balance issues
• Joint relaxation due to relaxin hormone leads to waddling and back pain.
• Diastasis recti (separation of abdominal muscles)

Gastrointestinal Changes

• hCG and changes in carbohydrate metabolism may cause morning sickness.
• Progesterone (a smooth muscle relaxer) can lead to constipation, heartburn, and bloating.
• Gums soften and bleed easily. Saliva production may increase
• Delayed emptying of the gallbladder and potential stone formation.