Physiological Changes in Pregnancy
Hematologic & Renal Changes
Antepartal Screening Tests
Fetal Surveillance
Signs, Symptoms & What’s Next?
100

This hormone maintains the uterine lining and prevents uterine contractions in early pregnancy.

What is progesterone?

Rationale:
Progesterone supports implantation, maintains the endometrium, and relaxes smooth muscle to prevent preterm contractions.

Nursing Actions:

  • Educate the patient on normal fatigue and constipation related to progesterone
  • Reinforce medication adherence if progesterone supplementation is prescribed
100

This pregnancy-related condition describes dilution of red blood cells due to increased plasma volume.

What is physiologic anemia of pregnancy?

Rationale:
Plasma volume increases more than RBC mass, causing lower hemoglobin/hematocrit values.

 Nursing Actions:

  • Monitor Hgb/Hct levels
  • Encourage iron-rich foods and supplements
100

This first-trimester blood test screens for chromosomal abnormalities using maternal serum markers.

What is cell-free fetal DNA testing (NIPT)?

Rationale:
NIPT analyzes fetal DNA in maternal blood to assess risk for trisomies 21, 18, and 13.

 Nursing Actions:

  • Provide non-directive counseling
  • Explain screening vs diagnostic testing
100

This test evaluates fetal heart rate response to movement.

What is the Nonstress Test (NST)?

Rationale:
A reactive NST reflects adequate oxygenation and neurologic function.

Nursing Actions:

  • Position patient laterally
  • Provide hydration or stimulation if non-reactive
100

A pregnant patient at 10 weeks reports nausea, fatigue, breast tenderness, and frequent urination.

What are normal presumptive signs of pregnancy?

Rationale:
These symptoms are commonly caused by rising hCG, estrogen, and progesterone in early pregnancy.

Nursing Actions & Interventions:

  • Reassure patient these are normal findings
  • Provide comfort measures for nausea and fatigue
  • Encourage hydration and small, frequent meals
200

This cardiovascular change causes a normal decrease in blood pressure during the second trimester.

What is systemic vasodilation with increased blood volume?

Rationale:
Peripheral vasodilation and increased plasma volume lead to a physiologic drop in BP, especially mid-pregnancy.

Nursing Actions:

  • Monitor BP trends, not single readings
  • Educate on slow position changes to prevent dizziness
200

This renal change causes increased urinary frequency during pregnancy.

What is increased glomerular filtration rate (GFR)?

Rationale:
Renal blood flow and GFR increase, leading to more urine production.

Nursing Actions:

  • Educate that frequency is normal
  • Assess for signs of UTI
200

This test, performed at 24–28 weeks, screens for gestational diabetes.

What is the 1-hour oral glucose challenge test?

Rationale:
Assesses placental-induced insulin resistance common in mid-pregnancy.

 Nursing Actions:

  • Educate on no fasting requirement (for screening test)
  • Review results and next steps if abnormal
200

This ultrasound-based test includes fetal breathing, tone, movement, and amniotic fluid volume.

What is the Biophysical Profile (BPP)?

Rationale:
Combines NST and ultrasound findings to evaluate fetal well-being.

Nursing Actions:

  • Explain scoring system
  • Report abnormal results promptly
200

A patient at 26 weeks has no symptoms but is scheduled to drink a glucose solution and have blood drawn 1 hour later.

What is the 1-hour oral glucose challenge test?

Rationale:
This screening test assesses for gestational diabetes during the period of peak insulin resistance.

Nursing Actions & Interventions:

  • Explain test purpose and process
  • Reinforce that fasting is not required
  • Discuss next steps if results are abnormal
300

This respiratory change improves oxygen delivery to the fetus.

What is increased tidal volume and oxygen consumption?

Rationale:
Pregnancy increases maternal oxygen needs by ~20%; deeper breaths enhance maternal-fetal oxygen exchange.

Nursing Actions:

  • Reassure mild dyspnea is normal
  • Teach upright positioning and rest periods
300

This condition may occur when the gravid uterus compresses the vena cava while supine.

What is supine hypotensive syndrome?

Rationale:
Compression decreases venous return and cardiac output, causing hypotension and dizziness.

Nursing Actions:

  • Position patient in left lateral position
  • Avoid prolonged supine positioning
300

This first-trimester diagnostic test obtains placental tissue to detect genetic abnormalities but does not assess neural tube defects.

What is Chorionic Villus Sampling (CVS)?

Rationale:
CVS involves sampling chorionic villi from the placenta between 10–13 weeks gestation to diagnose chromosomal and genetic disorders (e.g., trisomies, single-gene disorders). Because CVS does not sample amniotic fluid, it cannot measure alpha-fetoprotein (AFP) and therefore cannot detect open neural tube defects.

Nursing Actions & Interventions:

  • Verify gestational age prior to procedure (≥10 weeks to reduce risk of limb defects)
  • Provide pre-procedure education, including risks (miscarriage, infection, bleeding)
  • Obtain and verify informed consent
  • Monitor maternal vital signs and fetal heart tones post-procedure
  • Instruct patient to report vaginal bleeding, leakage of fluid, fever, or severe cramping
  • Reinforce need for follow-up screening (MSAFP or anatomy ultrasound) for neural tube defects later in pregnancy
300

Oligohydramnios is defined as this condition.

What is low amniotic fluid volume?

Rationale:
Can indicate placental insufficiency or fetal renal issues.

Nursing Actions:

  • Monitor fetal status closely
  • Prepare for increased surveillance or delivery
300

Second-trimester screening reveals elevated maternal serum AFP levels.

What are possible open neural tube defects?

Rationale:
Increased AFP may indicate defects such as spina bifida or anencephaly due to fetal protein leakage.

Nursing Actions & Interventions:

  • Clarify that this is a screening, not a diagnosis
  • Prepare patient for follow-up ultrasound or amniocentesis
  • Provide emotional support and clear explanations
400

The uterine growth out of the pelvis typically occurs at this gestational age.

What is 12 weeks gestation?

Rationale:
By 12 weeks, the uterus becomes an abdominal organ, which helps relieve early urinary frequency.

Nursing Actions:

  • Educate on normal anatomic changes
  • Assess fundal height at subsequent visits
400

Leukocytosis in pregnancy is considered normal due to this physiologic reason.

What is immune system adaptation to pregnancy?

Rationale:
WBC levels normally increase as part of pregnancy-related inflammatory and immune adaptations.

Nursing Actions:

  • Distinguish normal changes from infection
  • Correlate labs with clinical symptoms
400

This diagnostic antepartal test carries a small risk of miscarriage.

What is amniocentesis?

Rationale:
Amniotic fluid sampling provides definitive genetic information but is invasive.

Nursing Actions:

  • Obtain informed consent
  • Monitor for vaginal bleeding, leakage of fluid, or contractions
400

This Doppler study is used in high-risk pregnancies to assess placental blood flow.

What is umbilical artery Doppler velocimetry?

Rationale:
Abnormal flow indicates compromised placental perfusion.

Nursing Actions:

  • Communicate results to provider
  • Reinforce importance of follow-up care
400

A pregnant patient at 34 weeks reports decreased fetal movement. The provider orders external fetal monitoring without contractions.

What is a Nonstress Test (NST)?

Rationale:
An NST evaluates fetal heart rate accelerations in response to movement to assess oxygenation and neurologic function.

Nursing Actions & Interventions:

  • Position patient in left lateral position
  • Provide hydration or vibroacoustic stimulation if needed
  • Interpret and report reactive vs nonreactive results
500

This endocrine-mediated change explains why pregnant patients may experience nasal congestion, epistaxis, and gingival bleeding.

What is estrogen-related mucosal hyperemia and increased capillary fragility?

Rationale:
Elevated estrogen increases vascularity and capillary permeability of mucous membranes, affecting the nasal passages and gums.

Nursing Actions & Interventions:

  • Reassure patient this is a common physiologic change
  • Encourage gentle oral hygiene and saline nasal sprays
  • Assess for excessive bleeding that may indicate pathology
500

This specific coagulation change during pregnancy increases the risk for thromboembolic events.

What is pregnancy-induced hypercoagulability due to increased clotting factors and fibrinogen?

 Rationale:
Pregnancy increases clotting factors VII, VIII, IX, X, and fibrinogen to protect against hemorrhage at delivery, but raises DVT risk.

Nursing Actions & Interventions:

  • Assess for calf pain, swelling, warmth, or redness
  • Encourage ambulation and hydration
  • Teach avoidance of prolonged immobility and leg crossing
500

This abnormal maternal serum AFP result is most closely associated with open fetal neural tube defects.

What is elevated maternal serum alpha-fetoprotein (MSAFP)?

Rationale:
AFP leaks into maternal blood when fetal neural tube or abdominal wall defects are present.

Nursing Actions & Interventions:

  • Clarify that this is a screening, not diagnostic, test
  • Prepare patient for follow-up diagnostics (targeted ultrasound, amniocentesis)
  • Provide emotional support and accurate information
500

During a contraction stress test, this fetal heart rate response indicates uteroplacental insufficiency.

What are late decelerations?

Rationale:
Late decelerations occur after the peak of contractions and signal impaired placental oxygen transfer.

Nursing Actions & Interventions:

  • Stop oxytocin if infusing
  • Reposition to left lateral
  • Administer oxygen and IV fluids
  • Notify provider immediately
500

A 38-year-old pregnant patient at 11 weeks desires definitive genetic information. Placental tissue is sampled, but neural tube defects cannot be detected.

What is Chorionic Villus Sampling (CVS)?

Rationale:
CVS is a first-trimester diagnostic test used to detect chromosomal abnormalities, but it cannot assess AFP levels.

Nursing Actions & Interventions:

  • Verify gestational age (10–13 weeks)
  • Obtain informed consent
  • Monitor for bleeding, cramping, or infection
  • Reinforce need for later NTD screening