chapter 20

Chapter 20: Conditions Occurring During Pregnancy

Multiple Pregnancy

  • Definition of Multiple Pregnancy: Occurs when more than one fetus develops simultaneously in the uterus.

  • Dizygotic (Fraternal) Twins:
      - Result from the fertilization of two separate eggs.
      - Factors influencing dizygotic twinning rates include:
        - Use of fertility drugs.
        - Certain ethnicities known for higher rates of twinning.
        - Family history of twinning.

  • Monozygotic (Identical) Twins:
      - Occur due to the fertilization of one ovum, which then splits into two embryos.
      - Considered a random, spontaneous event.

  • Risks Associated with Multifetal Pregnancies:
      - Increased maternal and fetal risks, including:
        - Gestational diabetes
        - Hypertensive disorders of pregnancy (e.g., preeclampsia)
        - Pulmonary embolism
        - Fetal growth restriction
        - Fetal anomalies
        - Early pregnancy loss
        - Stillbirth
        - Placenta previa

Developmental Stages of Multiple Pregnancies

  • Cleavage Stages:
      - Cleavage days 1-3:
        - Formation of a morula.
      - Cleavage days 4-8:
        - Development into a blastocyst.
      - Cleavage days 8-13:
        - Morphological changes lead to either dichorionic or monochorionic structures.
        - Types include:
          - Dichorionic/Diamniotic
          - Monochorionic/Diamniotic
          - Monochorionic/Monoamniotic
        - Conjoined Twins: A high-risk outcome of late separation.

Cleavage Timing and Risk

  • Question: Is the following statement true or false? In monozygotic twinning, the earlier an ovum is cleaved, the higher the risk.

  • Answer: False
      - Reasoning: Earlier cleavage decreases the likelihood of twins sharing structures, thus reducing risk. Later cleavages result in shared structures, increasing the risk.

Hyperemesis Gravidarum

  • Definition: Hyperemesis gravidarum (HG) is characterized by severe nausea and vomiting during pregnancy.

  • Consequences of HG:
      - Weight loss
      - Malnutrition
      - Dehydration
      - Ketonuria
      - Electrolyte imbalances

  • Nursing Evaluation:
      - Signs of dehydration
      - Assessment of malnutrition
      - Laboratory tests as needed.

  • Treatment Options:
      - Antiemetics (note: some may have teratogenic effects)
      - Intravenous (IV) rehydration
      - Administration of parenteral electrolytes.

  • Risk Factors for Hyperemesis Gravidarum:
      - History of HG
      - Gestational trophoblastic disease
      - Multiple pregnancy
      - Hyperthyroidism
      - Pre-existing gastrointestinal diseases
      - Depression and anxiety
      - Carrying a female fetus.

Bleeding in Pregnancy: Miscarriage

  • Statistics: Up to 20% of females report vaginal bleeding in early pregnancy.

  • Associated Risks: Potential indicators of miscarriage, ectopic pregnancy, or gestational trophoblastic disease.

  • Definition of Miscarriage: A spontaneous abortion (pregnancy loss) occurring before 20 weeks gestation.

  • Causes: Approximately 70% of miscarriages are linked to chromosomal abnormalities.

  • Evaluation for Pregnancy Loss:
      - Symptoms: bleeding, cramping, passage of tissue.
      - Use of ultrasound and beta hCG level assessments.

Types of Spontaneous Abortion

Type

Clinical Findings

Care Considerations

Complete

Patient reports passing clots and tissue with heavy cramping and decreased bleeding.

Supportive measures; medical intervention typically unnecessary if all tissue passes without infection or hemorrhage. Watchful waiting up to 6 weeks may allow spontaneous passage.

Missed

Amenorrhea noted; cervix closed with no tissue passage.

Supportive measures; dilation and curettage (D&C) if necessary.

Inevitable

Heavy cramping and bleeding, some passage of tissue. Cervix is open.

D&C or dilation and evacuation as needed; careful monitoring.

Recurrent

Defined as two or more clinically documented losses or three pregnancies in a row.

Requires thorough evaluation and potential intervention.

Bleeding in Pregnancy: Ectopic Pregnancy

  • Definition: A pregnancy occurring outside the uterus, typically in the fallopian tube.

  • Risk Factors:
      - History of pelvic infections
      - Previous ectopic pregnancies
      - History of subfertility or fertility treatments
      - Smoking
      - Increased age.

  • Signs and Symptoms: Severe pelvic pain, possible shoulder pain, and vaginal bleeding.

  • Diagnosis: Serial beta hCG testing and transvaginal ultrasound.

  • Treatment: Can be medical or surgical, based on timing and patient condition.

Bleeding in Pregnancy: Gestational Trophoblastic Disease (GDP)

  • Definition: Also known as molar pregnancy; a nonviable mass of trophoblastic tissue.

  • Characteristics: High beta hCG levels, potential for abnormal growth and spread beyond the uterus.

  • Diagnosis and Treatment:
      - Diagnosed via ultrasound.
      - Treatment options include hysterectomy, D&C, possible chemotherapy, and serial monitoring of beta hCG levels. A subsequent pregnancy should be avoided for one year.

Hypertensive Disorders of Pregnancy: Gestational Hypertension

  • Definition: Diagnosed by a systolic blood pressure of greater than 140 mm Hg and/or diastolic blood pressure of 90 mm Hg or higher without protein in urine or signs of organ dysfunction after 20 weeks.

  • Complications:
      - Up to 50% of patients may develop preeclampsia.
      - Risks of preterm birth, small for gestational age (SGA) infants, and placental abruption.

Preeclampsia and Eclampsia

  • Preeclampsia Incidence: Occurs in 2% to 5% of pregnancies.

  • Potential Complications Include:
      - Oligohydramnios (low amniotic fluid)
      - Placental abruption
      - Intrauterine growth restriction (IUGR)
      - Renal damage, pulmonary edema, cerebral edema, and hemorrhage.
      - Thrombocytopenia (platelet count <100,000/mm³).

  • Eclampsia: Defined as preeclampsia with the occurrence of tonic-clonic seizure activity without known cause.

Diagnosis of Preeclampsia

  • Criteria:
      - Systolic BP ≥140 mm Hg and/or diastolic BP ≥90 mm Hg (on two occasions at least 4 hours apart) in a patient with prior normotension.
      - Proteinuria of 300 mg or higher in a 24-hour urine sample or protein:creatinine ratio ≥0.3.
      - New-onset hypertension with or without proteinuria and/or additional criteria such as low platelet count or elevated liver enzymes.

Monitoring and Management of Preeclampsia

  • Assessment Includes:
      - Blood pressure monitoring
      - Urine output and lab tests
      - Symptoms like headache, vision changes, or abdominal pain.

  • Treatment Includes:
      - Aspirin and calcium for high-risk patients
      - Outpatient monitoring for mild cases
      - Induction of delivery for severe cases.
      - Magnesium sulfate to prevent seizures.
      - Control hypertension with IV antihypertensives.

Magnesium Sulfate for Preeclampsia/Eclampsia

  • Administered by:
      - IV with a loading dose of 4-6 g over 15-30 minutes, followed by 1-3 g/hour maintenance to maintain serum levels between 4-7 mEq/L.

  • Signs of Magnesium Toxicity:
      - Respiratory depression, oliguria, absent reflexes, lethargy, slurred speech, muscle weakness, loss of consciousness.

  • Interventions for Toxicity:
      - Stop infusion immediately and administer calcium gluconate (1 g slow IV push).

Gestational Diabetes

  • Prevalence: Occurs in about 6% of pregnancies, characterized by insulin resistance and elevated blood glucose levels.

  • Screening Measures:
      - High-risk patients screened during first prenatal visit; all patients screened between 24-28 weeks.
      - Screening test: Non-fasting 50 g glucose tolerance test; if glucose >130, diagnostic tests follow (fasting 100 g tolerance test).

Diagnostic Values for Gestational Diabetes

  • Fasting: ≥95 mg/dL

  • 1 Hour: ≥180 mg/dL

  • 2 Hours: ≥155 mg/dL

  • 3 Hours: ≥140 mg/dL

Risks and Management

  • Risks Linked to Gestational Diabetes:
      - Stillbirth and fetal macrosomia.

  • Treatment Approaches:
      - Diet, exercise, and potentially medication (insulin if required).

Patient Teaching for Gestational Diabetes

  • Nutritional Guidelines:
      - Monitor carbohydrate intake (35%-40% of calories)
      - Protein (20%-30%) and fats (40%-45%).
      - Regular meals/snacks to maintain blood glucose levels.
      - Keep a food log including glucose monitoring.

Care Considerations

  • No consensus on fetal monitoring for well-controlled cases.

  • Medications may warrant closer monitoring.

  • Optimal outcomes depend on controlled blood sugars:
      - Fasting <95 mg/dL, 1-hour postprandial <140 mg/dL, or 2-hour postprandial <120 mg/dL.

  • Preferred delivery: spontaneous vaginal birth; induction or cesarean may be needed for poorly controlled cases.

Infections in Pregnancy

  • Types of infections: STIs, vaginitis, TORCH infections, UTIs.
      - Chlamydia and Gonorrhea: Can lead to preterm labor, low birth weight, postpartum endometritis; treated with antibiotics.
      - Herpes: Avoidance strategies and potential cesarean delivery if lesions are present.
      - HIV Positive: Pregnancy is not contraindicated; cesarean may reduce transmission risk.
      - Hepatitis B Positive: Newborns should receive vaccinations shortly after birth.

Bacterial Vaginosis and TORCH Infections

  • Bacterial Vaginosis: Generally benign but poses risks during pregnancy.

  • TORCH Infections: Include Toxoplasmosis, Other infections, Rubella, Cytomegalovirus, and Herpes; linked to fetal anomalies and may be asymptomatic in mothers.

Cervical Insufficiency

  • Definition: Painless dilation of the cervix in the second trimester, increasing miscarriage or preterm birth risk.

  • Diagnosis: Second-trimester loss history and cervical length assessment via ultrasound.

  • Treatment Options: Includes progesterone supplementation and cervical cerclage procedures.

Types of Cervical Cerclage

  • McDonald Cerclage: A common procedure for cervical insufficiency.

  • Shirodkar Cerclage

  • Transabdominal Cerclage

Trauma in Pregnancy

  • Causes: Motor vehicle accidents, falls, intimate partner violence.

  • Care Considerations:
      - Place wedge under right hip to minimize hypotension from supine positioning.
      - Monitor closely for hypoxia; chest compressions may be less effective later in pregnancy.
      - Assess both mother and fetus for trauma complications.

Intrauterine Growth Restriction (IUGR)

  • Definition: A condition indicating complications during pregnancy, diagnosed in about 10% of pregnancies.

  • Differentiation between SGA and IUGR:
      - SGA (Small for Gestational Age): Fetus measures under the 10th percentile.
      - IUGR: Indicates pathological growth issues preventing the fetus from reaching its growth potential.

  • Causes of IUGR Include:
      - Asymmetric IUGR: Uteroplacental insufficiency, maternal hypertensive disorders, malnutrition, etc.
      - Symmetric IUGR: TORCH infections, substance abuse, fetal chromosomal abnormalities, etc.

Amniotic Fluid Volume Disorders

Polyhydramnios

  • Definition: Excessive amniotic fluid, potentially linked to diabetes or twin-to-twin transfusion.

  • Associated Risks: Preterm labor, birth defects, postpartum hemorrhage.

  • Diagnosis: Ultrasound measuring the four largest pockets of fluid; AFI ≥24 cm indicates abnormality.

  • Treatment Options: Amnioreduction, indomethacin administration, induction of labor if necessary.

Oligohydramnios

  • Definition: Decreased amniotic fluid, often linked to fetal anomalies or premature rupture of membranes.

  • Diagnosis: Ultrasound revealing AFI ≤5 cm or largest pocket ≤2 cm.

  • Treatment: May involve amnioinfusion of Ringer's lactate.

Risks of Amniotic Fluid Volume Disorders

  • Risks Include:
      - Preterm birth
      - Umbilical cord prolapse
      - Variable decelerations in fetal heart rate.

Dermatoses of Late Pregnancy

Intrahepatic Cholestasis

  • Causes: Impaired bile flow.

  • Symptoms: Pruritus, clay-colored stools, jaundice, fatigue.

  • Goal of Treatment: Minimize itching, stabilize bile acid levels, and deliver by 36-37 weeks.

  • Resolution: Typically resolves by end of pregnancy.

Pruritic Urticarial Papules and Plaques of Pregnancy (PUPPP)

  • Description: Highly pruritic lesions possibly linked to an inflammatory process.

  • Treatment Includes: Oral or topical corticosteroids and antihistamines. Resolution typically within weeks post-delivery.