Learning Objectives
By the end of this section, you will be able to:
- Explain the pathophysiology of cardiovascular preexisting conditions placing the birth at risk
- Explain the pathophysiology of endocrine preexisting conditions placing the birth at risk
- Explain the pathophysiology of musculoskeletal preexisting conditions placing the birth at risk
- Explain the pathophysiology of nutritional preexisting conditions placing the birth at risk
Preexisting conditions of the pregnant person can cause increased risk at the time of birth. Some conditions cause birth to be expedited by induction of labor. Other conditions require increased surveillance during pregnancy and birth. Conditions such as heart disease, hypertension, and diabetes mellitus can cause uteroplacental insufficiency and morbidity and mortality of the pregnant person. Musculoskeletal and nutritional complications can cause difficulty during labor for the laboring person or fetus. Knowledge of these preexisting conditions and their effects on the patient and fetus is integral to the nurse monitoring for and managing complications during labor and birth.
Cardiovascular Conditions
Cardiovascular disease in pregnancy accounts for a large percentage of maternal morbidity and mortality in the United States every year (ACOG, 2019c). Cardiovascular disease includes congenital and acquired heart disease, with acquired being on the rise. (See Chapter 12 Pregnancy at Risk for further discussion of cardiac disease and pregnancy.) People with heart disease should labor at an appropriate-level hospital with a care team consisting of an obstetrician, maternal-fetal medicine specialist, cardiologist, and anesthesiologist prepared for any complications.
During labor, preexisting hypertension puts the laboring person at risk for stroke and myocardial infarction; hypertension puts the fetus at risk for uteroplacental insufficiency and fetal distress. Blood pressure must be monitored more closely to determine if antihypertensive medications are necessary during labor. Fetal monitor tracings must be evaluated often to ensure proper fetal oxygenation.
Heart Disease
Heart disease is also linked to maternal mortality. Some cardiac conditions require alternative plans for labor and birth. Persons with stable heart disease can safely give birth vaginally at 39 weeks’ gestation. Pregnant persons on anticoagulant therapy for cardiac disease will discontinue those medications approximately 12 hours prior to a scheduled induction or cesarean birth (ACOG, 2019c). Pulmonary edema and cardiac arrhythmias require cardiac monitoring during labor. Strict fluid balance is required for prevention of pulmonary edema. Antibiotics could be required during labor to prevent endocarditis. Epidural anesthesia for labor pain can reduce the risk of cardiac arrhythmias (ACOG, 2019c).
The mode of delivery should be discussed with the pregnant person and a multidisciplinary team. People with severe heart failure and acute or chronic aortic dissection should give birth via cesarean birth (Ruys et al., 2013). Marfan syndrome can cause an enlarged aortic root that increases the risk for aortic dissection. If the aortic root is greater than 40 mm, the person should give birth via cesarean birth (Canobbio et al., 2017). People with aortic stenosis and pulmonary hypertension can birth only by passive delivery, meaning avoiding pushing using the Valsalva maneuver (Canobbio et al., 2017). Forceps- or vacuum-assisted delivery is required. Nursing interventions include monitoring vital signs, turning the laboring person to the lateral recumbent position, cardiac monitoring, and closely monitoring fluid input and output (Canobbio et al., 2017).
Hypertension
Preexisting hypertension is the elevation of blood pressure related to peripheral vascular resistance and/or increased cardiac output prior to 20 weeks’ gestation. See Chapter 12 Pregnancy at Risk for a full discussion of preexisting hypertension in pregnancy.
Preexisting hypertension creates complications during labor by causing uteroplacental insufficiency leading to fetal distress. Severe preexisting hypertension can lead to stroke, cardiovascular disease, and death. Emergency antihypertensive medications should be ordered by the health-care provider when severe hypertension is noted during labor, birth, or the postpartum period.
Diabetes Mellitus
Diabetes mellitus (DM) is a metabolic disorder causing elevated blood glucose due to dysfunction in insulin secretion or insulin action (Banday et al., 2020). Diabetes mellitus can be classified as type 1 DM, type 2 DM, or gestational DM. Type 1 DM has been called juvenile-onset diabetes and is caused by an autoimmune disorder that destroys the beta cells of the pancreas and requires insulin. Type 2 DM has also been called non–insulin-dependent diabetes. Type 2 DM is characterized by insulin resistance and beta cell dysfunction (Banday et al., 2020). Preexisting diabetes can cause complications during labor and birth. The most common complication is neonatal hypoglycemia. If the glucose of the laboring person is well controlled, risk for neonatal hypoglycemia is reduced. Other risk factors include cesarean birth, macrosomia, and preterm labor or birth. Shoulder dystocia of the infant is a risk for persons with diabetes. The nurse communicates with the health-care team to be prepared for a possible shoulder dystocia (see 19.7 Obstetrical Emergencies). The nurse will also monitor the laboring person for hyper- and hypoglycemia.
Musculoskeletal Conditions
Several musculoskeletal conditions can affect pregnancy and birth. Muscular dystrophy, a genetic neuromuscular disease that causes weakness and breakdown of skeletal muscles, can lead to preterm birth, intrauterine growth restriction, and congenital malformation (Petrangelo, 2018). Persons with cerebral palsy, a permanent disorder of movement caused by a lesion in the developing brain, are at higher risk for preterm birth, small-for-gestational-age infants, and low 5-minute Apgar scores (Sundelin et al., 2020). Myasthenia gravis is an autoimmune disorder causing muscular weakness that worsens with movement (Roche & Bouhour, 2021). Vaginal operative birth and cesarean birth are more common in those with myasthenia gravis. Epidural anesthesia is appropriate; however, opiates and general anesthetics should be avoided (Roche & Bouhour, 2021). Persons with musculoskeletal issues such as cerebral palsy or an amputation might need special equipment during labor and birth. The role of the nurse is to support the laboring person and assist with ambulation, position changes, and use of special equipment.
Nutritional Status
Nutrition can positively or negatively affect the pregnant person and fetus. Pregnant persons with inflammatory bowel disease, pancreatitis, and intestinal parasites have increased malabsorption (Rahimian, 2019). Malnutrition and malabsorption of nutrients may cause intrauterine growth restriction. The growth-restricted fetus can have increased complications during labor due to uteroplacental insufficiency and lack of fetal reserve. Eating disorders such as anorexia or bulimia can affect absorption of nutrients in the pregnant person and fetus, leading to growth restriction and fetal anomalies (Sebastiani et al., 2020). The most common fetal complications associated with eating disorders are being small for gestational age, fetal growth restriction, microcephaly, and intraventricular hemorrhage. The role of the nurse is to assess the laboring person’s nutritional status upon admission. If malnutrition or malabsorption is suspected, the nurse will monitor for signs of uteroplacental insufficiency.