NCLEX Review Guide: Pregnancy Signs

Presumptive (Subjective) Signs

• Amenorrhea: Absence of menstruation is typically the first sign that prompts a woman to suspect pregnancy, occurring after conception when implantation leads to hormonal changes that prevent menstruation.
• Nausea and vomiting: Morning sickness affects 50-80% of pregnant women, typically beginning around 4-6 weeks gestation and resolving by the second trimester, though it can occur at any time of day.
• Breast changes: Breasts become tender, swollen, and more sensitive due to increased estrogen and progesterone, with darkening of the areola and more prominent Montgomery's tubercles appearing by 6-8 weeks.
• Fatigue: Profound tiredness is common in early pregnancy due to rising progesterone levels, increased metabolic demands, and physiologic anemia.
• Urinary frequency: Increased blood flow to the kidneys and pressure on the bladder from the enlarging uterus causes frequent urination, particularly noticeable in the first and third trimesters.
• Food cravings or aversions: Altered taste preferences and specific food desires or revulsions are common and may be related to hormonal changes affecting taste and smell.

Probable (Objective) Signs

• Positive pregnancy test: Home pregnancy tests detect human chorionic gonadotropin (hCG) in urine, while blood tests can detect pregnancy earlier (approximately 7-12 days after conception).
• Goodell's sign: Softening of the cervix occurs around 4-6 weeks gestation due to increased vascularity and edema from hormonal influences.
• Hegar's sign: Softening of the lower uterine segment between the cervix and fundus, detectable during bimanual examination around 6-8 weeks gestation.
• Chadwick's sign: Bluish-purple discoloration of the vagina, cervix, and vulva due to increased vascularity and venous congestion, visible by 6-8 weeks.
• Uterine enlargement: Progressive growth of the uterus from pear-sized to filling the entire pelvis and eventually the abdominal cavity, with specific measurements expected at different gestational ages.
• Braxton Hicks contractions: Irregular, painless uterine contractions that may be felt as early as the second trimester but become more noticeable in the third trimester.

Positive (Diagnostic) Signs

• Fetal heart tones: Detection of fetal heart activity separate from the maternal pulse, audible with a Doppler device by 10-12 weeks gestation (140-160 beats per minute).
• Fetal movements felt by examiner: Quickening (fetal movement) is initially felt by the mother around 16-20 weeks but can be detected by an experienced examiner shortly thereafter.
• Visualization of the fetus: Ultrasound can detect a gestational sac as early as 4-5 weeks, fetal pole and cardiac activity by 6-7 weeks, and detailed fetal anatomy by 18-20 weeks.
• Palpation of fetal parts: The examiner can feel distinct fetal parts through the maternal abdomen typically after 20 weeks gestation using Leopold's maneuvers.

Cardiovascular System Changes

• Blood volume increases by 30-50% (1000-1500 mL) by term, with plasma volume increasing proportionally more than red cell mass, leading to physiologic anemia of pregnancy.
• Cardiac output increases by 30-50% by the early third trimester, with stroke volume and heart rate both contributing to this increase.
• Blood pressure typically decreases in the second trimester due to peripheral vasodilation, then returns to pre-pregnancy levels by term.
• Supine hypotensive syndrome can occur when the gravid uterus compresses the inferior vena cava in the supine position, reducing venous return and cardiac output.

Respiratory System Changes

• Oxygen consumption increases by 15-20% to meet the metabolic demands of the mother and fetus.
• Diaphragm elevates by up to 4 cm at term, but compensatory thoracic expansion maintains and slightly increases lung capacity.
• Respiratory rate remains relatively unchanged, but tidal volume increases by 30-40%, resulting in increased minute ventilation.
• Progesterone-induced hyperventilation leads to respiratory alkalosis with compensatory renal bicarbonate excretion, creating a state of compensated respiratory alkalosis.

Gastrointestinal System Changes

• Decreased gastric motility and prolonged gastric emptying time due to progesterone and mechanical displacement by the enlarging uterus.
• Relaxation of the lower esophageal sphincter contributes to gastroesophageal reflux, experienced as heartburn by up to 80% of pregnant women.
• Decreased intestinal motility leads to increased water absorption and constipation in approximately 40% of pregnancies.
• Gallbladder contractility decreases while bile becomes more concentrated, increasing the risk of gallstone formation.

• Pregnancy signs are classified as presumptive (subjective symptoms), probable (objective findings), and positive (diagnostic confirmation) based on their specificity and reliability.
• Presumptive signs like amenorrhea, nausea, and breast changes appear early but cannot definitively diagnose pregnancy.
• Probable signs include cervical and uterine changes (Goodell's, Hegar's, Chadwick's signs) and positive pregnancy tests, which strongly suggest but don't absolutely confirm pregnancy.
• Positive signs such as fetal heart tones, fetal movement felt by the examiner, and visualization of the fetus provide absolute confirmation of pregnancy.
• Physiological adaptations during pregnancy affect virtually every body system to accommodate the growing fetus while maintaining maternal homeostasis.

NCLEX Application

• Focus on categorizing signs correctly as presumptive, probable, or positive when answering questions about pregnancy diagnosis.
• Understand the expected timeline of when different signs appear to properly assess gestational age scenarios.
• Recognize that NCLEX often tests on distinguishing normal physiological changes from pathological conditions in pregnancy.
• Be prepared to identify appropriate nursing assessments and interventions related to common pregnancy discomforts based on underlying physiological changes.

Assessment Techniques

Leopold's Maneuvers

1. First maneuver: Stand facing the patient's head and palpate the fundus to determine what fetal part occupies the fundus (head or breech).
2. Second maneuver: Place hands on either side of abdomen to locate the fetal back (smooth, firm surface) and small parts (irregular, nodular feeling).
3. Third maneuver: Grasp the lower portion of the abdomen just above the symphysis pubis to determine what fetal part is presenting (head feels hard and round, breech feels softer and irregular).
4. Fourth maneuver: Face the patient's feet and use both hands to palpate the sides of the uterus to locate the cephalic prominence (brow) and determine engagement.