Chapter 20 – Pregnancy at Risk: Selected Health Conditions & Vulnerable Populations

Conditions Causing At-Risk Pregnancies

• Major categories that heighten pregnancy risk:
• Diabetes (pre-existing and gestational)
• Cardiac & respiratory disorders
• Hematologic disorders – anemia, hemoglobinopathies
• Autoimmune diseases (localized & systemic)
• Specific infections (TORCH, HIV, TB, etc.)
• Hypertensive disorders
• Substance misuse, extremes of reproductive age, obesity

Diabetes Mellitus & Pregnancy

Classifications

• Conventional medical classes → Type 1, Type 2, impaired fasting glucose, impaired glucose tolerance, gestational diabetes (GDM)
• Obstetric view during pregnancy:
• Pregestational diabetes – any type 1 or type 2 existing before conception
• Gestational diabetes – glucose intolerance first recognized during pregnancy (NOT automatically type 2)
• Table 20.1 contrasts the two groups.
• NCLEX-style Q&A recap
• Q #1: “A patient who develops diabetes during pregnancy has type 2 diabetes.” → False (correct term = GDM).

Pathophysiology in Pregnancy

• Growing fetus increasingly demands glucose; maternal metabolism shifts to support this.
• Placental hormones (human placental lactogen, progesterone, growth hormone, cortisol) create progressive insulin resistance → post-prandial hyperglycemia.
• Trimester pattern:
• 1st trimester → ↑ insulin sensitivity, risk of maternal hypoglycemia.
• 2nd & 3rd trimesters → marked insulin resistance, maternal hyperglycemia.
• Maternal effects: polyhydramnios, ketoacidosis, hypertensive disorders, birth injury (shoulder dystocia), increased C-section rate, postpartum hemorrhage.
• Fetal/neonatal effects (Table 20.1): macrosomia, congenital anomalies (if pregestational DM), IUGR (if vascular involvement), RDS, neonatal hypoglycemia, polycythemia, hyperbilirubinemia.

Therapeutic Management

• Pre-conception counseling mandatory for pregestational DM.
• Tight glycemic targets:
• HbA1c < 7\% pre-conception & through gestation.
• SMBG goals – fasting <95\,\text{mg/dL}, 1-hr post-prandial <120\,\text{mg/dL}.
• MNT (medical nutrition therapy): diabetes plate method, nutrient-dense complex CHO, limit sweetened drinks, 3 structured meals plus snacks.
• Physical activity: 20!\text{–}!30\text{ min} most days unless contraindicated.
• Medications: insulin considered gold standard; some oral agents (metformin, glyburide) used.
• Maternal-fetal surveillance: serial US, BPP, NST, amniocentesis for lung maturity, AFP levels.
• Intrapartum: continuous glucose checks, insulin infusion protocols; plan for shoulder dystocia (large fetus).
• Postpartum: insulin needs fall sharply; encourage breastfeeding (facilitates maternal glycemic control & reduces future DM2 risk).

Nursing Assessment & Management

• Screen all at first prenatal visit; high-risk repeat at 24–28 wks (50 g 1-hr GCT followed by 3-hr OGTT if abnormal).
• Maternal labs each trimester: urine protein/ketones/nitrates/leukocyte esterase, serum creatinine, HbA1c q4–6 wks, first-trimester eye exam.
• Daily management teaching: SMBG technique, urine dip-sticks, hypoglycemia recognition, meal planning, exercise safety.
• Monitor fundal height – hydramnios indicator; monitor BP – preeclampsia risk.
• Teach long-term risk: history of GDM → 35–60 % chance of DM2 within 10 yrs.

Cardiac Disorders in Pregnancy

Congenital Lesions (Table 20.3)

• Tetralogy of Fallot (components: VSD, overriding aorta, pulmonary stenosis, right-ventricular hypertrophy).
• ASD, VSD, Patent ductus arteriosus.

Acquired Conditions

• Mitral valve prolapse, mitral stenosis, aortic stenosis.
• Peripartum cardiomyopathy (appears final month → 5 mo postpartum).
• Myocardial infarction (rare but ↑ incidence with advanced age & obesity).

Functional (NYHA) Classification – predicts obstetric risk

• Class I – asymptomatic with ordinary activity.
• Class II – symptomatic (dyspnea, chest pain) with ↑ activity.
• Class III – symptomatic (fatigue, palpitations) with minimal activity.
• Class IV – symptomatic at rest.
• Q #2 verifies: Class II symptomatic on exertion → True.

Pathophysiology & Obstetric Implications

• Pregnancy ↑ plasma volume 40\%, HR +10!!\text{–}!15\,\text{bpm}, cardiac output +30!\% → stress heart; peaks at 28–32 wk & during labor.
• Delivery: pain, anxiety, Valsalva raise workload; immediate postpartum autotransfusion (~500 mL uterine blood) critical period.

Management Principles

• Pre-conceptual counseling, baseline EKG/Echo.
• Frequent prenatal visits; multidisciplinary team (cardio-OB).
• Drugs:
• Diuretics (furosemide) for fluid control.
• Beta-blockers / calcium-channel blockers to lower HR & afterload.
• Anticoagulation: LMWH preferred; warfarin crosses placenta (teratogenic, fetal hemorrhage).
• Activity: scheduled rest, avoidance of strenuous exercise, prophylactic antibiotics if indicated.
• Nutrition: limit sodium, adequate protein & iron, weight gain per guidelines.
• Fetal monitoring: growth scans, kick counts, NSTs.
• Intrapartum: continuous hemodynamic monitoring, side-lying, epidural (↓ pain & preload), forceps/vacuum to shorten 2nd stage, avoid fluid overload.

Chronic Hypertension

• Defined: BP ≥140/90 before 20 wk or persisting >12 wk postpartum.
• Therapy: lifestyle (DASH diet, exercise), low-dose aspirin, antihypertensives (labetalol, nifedipine, methyldopa). Severe HTN may require \ge180/110 control.
• Monitor for superimposed preeclampsia, placental abruption, IUGR.

Respiratory Disorders

Asthma

• Pregnancy physiology: diaphragm elevates, ↑ tidal volume, ↓ residual capacity.
• Triggers: allergens, infection, smoke, exercise.
• Pharmacotherapy safe in pregnancy: inhaled corticosteroids (budesonide), short-acting beta agonists (albuterol), long-acting (salmeterol) if moderate-persistent.
• Nursing:
• Assess s/s – wheeze, chest tightness, cough.
• Educate: trigger avoidance, peak-flow monitoring, vaccinations, smoking cessation, follow-up with pulmonologist.
• Labor: continuous O2 sat, avoid prostaglandin F2α (bronchospasm).

Tuberculosis

• Standard 3-drug regimen: isoniazid (INH) + rifampin + ethambutol; pyrazinamide debated.
• Screening: PPD, interferon-gamma assay; CXR with abdominal shielding if positive.
• Nursing: assess risk factors (close contact, homelessness, HIV), emphasize adherence (DOT therapy), teach infection control, promote nutrition & prenatal care.

Hematologic Disorders

Iron-Deficiency Anemia

• Cause: inadequate intake, closely spaced pregnancies, GI malabsorption.
• Diagnostic cutoffs (ACOG): \text{Hgb}<11\,\text{g/dL} 1st/3rd tri; <10.5 2nd tri; Hct <33 %.
• Clinical picture: fatigue, pallor, tachycardia, pale mucosa, ↑ infection risk.
• Q #3 correct choice: fatigue.
• Management:
• 30 mg iron daily prenatal vitamin; if anemic, 60–120 mg elemental iron + vit C; take between meals, manage GI upset (fiber, fluids, stool softener).
• Dietary counseling: red meat, legumes, leafy greens, iron-fortified cereals.

Thalassemia

• Genetic ↓ or absent globin synthesis.
• Alpha (minor) – mild microcytic anemia; pregnancy usually tolerated.
• Beta (major) – severe anemia, transfusion-dependent; pregnancy rare due to infertility & high morbidity.
• Avoid iron overload – chelation (deferoxamine) teratogenic → deferred; monitor ferritin.

Sickle Cell Disease (Hb S)

• Vaso-occlusive crises precipitated by hypoxia, dehydration, acidosis, infection.
• Pregnancy risks: crisis, infection, preeclampsia, PTL, IUGR, IUFD.
• Care:
• Prevent crisis – hydration, avoid extremes temp, prompt infection treatment.
• Crisis: O2, IV fluids, opioids, transfusion if severe.
• Labor: left lateral, supplemental O2, continuous FHR, epidural (↓ stress); postpartum DVT prophylaxis (TED hose, early ambulation).

Autoimmune Diseases

• Localized – target single organ (e.g., Hashimoto thyroiditis, Graves → manage maternal thyroxine levels; uncontrolled Graves risks fetal thyrotoxicosis).
• Systemic – lupus erythematosus (SLE) multi-organ; requires pregnancy in remission ≥6 mo; risks: miscarriage, preeclampsia, preterm birth, neonatal lupus.
• General principle: use lowest teratogen-free dose of immunosuppressants (hydroxychloroquine, azathioprine acceptable; methotrexate contraindicated).

Infections of Significance (Remember TORCH-Plus)

• Cytomegalovirus (CMV) – body fluids; congenital CMV → sensorineural hearing loss, neuro-disability.
• Rubella – “German measles” → fetal cataracts, cardiac defects, deafness, stillbirth; live vaccine contraindicated in pregnancy; vaccinate postpartum.
• Herpes simplex virus – neonatal disease of brain/eye/skin; prophylactic acyclovir from 36 wk; C-section if active lesions.
• Hepatitis B – blood/sexual fluid; maternal HBsAg + → give newborn HBIG + first vaccine within 12 hr.
• Varicella-Zoster – congenital varicella syndrome; live vaccine pre-pregnancy only.
• Parvovirus B19 – “slapped-cheek” rash; causes fetal anemia, hydrops; middle cerebral artery Dopplers to gauge severity.
• Group B Streptococcus – leading neonatal sepsis/meningitis cause; screen 35–37 wk; intrapartum IV penicillin if positive or ROM >18 hr, PTL.
• Toxoplasmosis – cat litter, soil, raw meat; fetal neuro damage, hydrocephalus; prevention: cook meat, gloves gardening, avoid litter boxes.
• HIV – see separate section.

HIV in Pregnancy

Impact & Goals

• Maternal immunosuppression + concern for vertical transmission (in utero, intrapartum, breastfeeding).
• Combined ART reduces transmission to <1 %.

Therapeutic Protocol

• Oral triple ART twice daily beginning 14 wk through delivery.
• IV zidovudine during labor if viral load >1000 copies/mL.
• Newborn: oral zidovudine syrup for first 6 weeks.
• Mode of birth: elective C-section at 38 wk if viral load >1000; possible vaginal if <1000 copies/mL, membranes intact, good progress.
• Breastfeeding: acceptable if maternal viral load undetectable and adherent to ART (per WHO), but in some countries formula recommended.

Nursing Care

• Pre-/post-test counseling, consent.
• Screen & treat coinfections (STIs, TB).
• Teach strict ART adherence, safe sex, infant feeding decisions, mental-health support, family planning.
• Q #4 recap: Cesarean is recommended but not mandatory—decision individualized.

Vulnerable Populations

Pregnant Adolescents

• Assessment: future goals, support systems, developmental knowledge, finances, anger-resolution skills, parenting readiness, community resources.
• Management:
• Supportive counseling, linkage to WIC, school continuation, prenatal classes tailored to teens.
• Frequent assessments of growth, anemia, preeclampsia.
• Education on nutrition (higher Ca, Fe), contraception for future spacing, stress reduction.

Advanced Maternal Age (≥35 yr)

• ↑ risks: infertility, chromosomal abnormalities (e.g., Down syndrome), GDM, HTN, placenta previa, C-section.
• Nursing actions: preconception health optimization, early screening (NIPT, quad screen, amniocentesis), encourage exercise & balanced diet, monitor fetal growth.

Obesity in Pregnancy (not detailed but listed)

• Risks: GDM, preeclampsia, macrosomia, operative delivery, sleep apnea.
• Interventions: weight-gain counseling (IOM guidelines), dietitian referral, thromboprophylaxis as needed.

Substance Misuse

• Common agents & fetal effects (Table 20.6):
• Alcohol → Fetal Alcohol Spectrum Disorder (microcephaly, facial dysmorphisms, cognitive deficits). Illustration slide: low nasal bridge, short palpebral fissures, flat midface, epicanthal folds, short nose, thin upper lip, minor ear anomalies, receding jaw.
• Nicotine/caffeine → LBW, PTL.
• Cocaine → placental abruption, preterm birth, fetal stroke.
• Marijuana → neurobehavioral impacts.
• Opiates → neonatal abstinence syndrome; methadone/buprenorphine maintenance preferred.
• Sedatives, methamphetamines → congenital anomalies, growth restriction.
• Nursing Approach: non-judgmental, build trust; comprehensive history, urine toxicology; collaborate with social services/CPS for positive newborn screen; brief interventions (SBIRT), referral to treatment, educate about breastfeeding considerations.

Ethical, Philosophical & Practical Considerations

• Informed decision-making vital (mode of birth in HIV, cardiac risk vs. pregnancy continuation, adolescent autonomy).
• Balance maternal autonomy with fetal well-being (e.g., refusal of GDM treatment → ethics consult).
• Public-health lens: screening programs (GBS, GDM) reduce neonatal morbidity at population level.
• Socioeconomic determinants: vulnerable groups need additional advocacy—transportation, insurance, nutrition assistance.

Key Numerical & Laboratory References (Quick Sheet)

• HbA1c target: <7\% • SMBG goals: Fasting <95\,mg/dL; 1-hr PP <120\,mg/dL • Iron-deficiency anemia threshold: Hgb <11 g/dL (1st/3rd tri), <10.5 g/dL (2nd) • NYHA classes I–IV – escalating symptom severity • BP definition chronic HTN: \ge140/90 before 20 wk or persisting >12 wk PP
• Cardio labor danger period: autotransfusion ≈500\,mL in first 24 hr PP
• HIV viral load cut-off for vaginal delivery: <1000\,copies/mL

Cross-Lecture Connections & Real-World Relevance

• Integrates physiology (metabolic, cardiovascular, hematologic adaptations) with pathologic exaggerations (GDM, cardiomyopathy).
• Emphasizes interprofessional collaboration—OB, endocrinology, cardiology, infectious disease, social work.
• Reflects current evidence-based guidelines (ACOG, ADA, CDC, WHO) ensuring test prep mirrors clinical practice.
• Highlights global health disparities: HIV, TB, malnutrition & anemia more prevalent in resource-limited settings.