Pregnancy, Labor, and Maternal Care Review

Medical Signs and Clinical Findings of Pregnancy

• Subjective (Presumptive) Signs: These are feelings or changes reported by the patient that suggest pregnancy but are not diagnostic. Examples include:

  • Fatigue: Often described as feeling very tired.

  • Nausea and Vomiting: Commonly known as "morning sickness."

  • Amenorrhea: Missed menstrual periods (may also be caused by stress or irregular cycles).

  • Hyperpigmentation of the skin: Occurs around $16$ weeks.

  • Quickening: The maternal sensation of fetal movement.

• Objective (Probable) Signs: These are physical changes observable by a clinician that strongly suggest pregnancy but are not absolute proof. Examples include:

  • Chadwick's Sign: A bluish-purple coloration of the cervix and vaginal mucosa.

  • Goodell's Sign: Softening of the cervix.

  • Hegar's Sign: Softening of the lower uterine segment.

  • Braxton Hicks Contractions: Intermittent, painless contractions occurring between $16$ and $28$ weeks; these prepare the body for labor but do not result in cervical change.

  • Abdominal Enlargement: Becomes noticeable around $14$ weeks.

  • Positive Pregnancy Test: While objective, it is considered a probable sign, not a positive one, because false positives/negatives can occur due to conditions like molar pregnancies.

• Positive (Diagnostic) Signs: These are findings that confirm the presence of a live embryo or fetus. Examples include:

  • Ultrasound Verification: Visualization of the embryo or fetus between $4$ and $6$ weeks.

  • Fetal Heart Sounds (Auscultation): Detected via Doppler around $10$ to $12$ weeks. Note: If heart sounds are not audible by $12$ weeks, mothers should be reassured as it may take more time; ultrasound is a more reliable early confirmation.

  • Palpable Fetal Movement: Experienced by a clinician (not the mother) around $20$ weeks.

Uterine and Cervical Changes During Gestation

• Uterine Growth: The uterus increases in size, weight, and length, changing from a pear shape to an oval shape as the fetus grows.

• Fundal Height Measurements:

  • At $20$ weeks of gestation, the fundus is typically at the level of the umbilicus.

  • Between $20$ and $36$ weeks, the fungal height in centimeters should roughly equal the weeks of gestation (e.g., $20$ weeks = $20\,cm$; $28$ weeks = $28\,cm$).

  • Discrepancies in measurement may trigger further ultrasound evaluation to ensure proper fetal growth.

• Cervical Changes:

  • Mucus Plug: The loss of the mucus plug is a precursor to labor.

  • Bloody Show: A mixture of blood and mucus from the cervix as it prepares for labor.

  • Vaginal Changes: Increased vascularity and thickening occur during pregnancy.

Clinical Evaluation of Labor

• Definition of Labor: True labor is defined by cervical change (dilation and effacement). Contractions alone, regardless of timing or discomfort, do not constitute labor if the cervix remains unchanged (e.g., staying at $2\,cm$ while contracting every $2$ minutes).

• The Vaginal Exam:

  • The assessment of dilation is subjective and based on the provider's hand width. It can be challenging if the fetal head is in the way or if the patient is only $2$ to $3\,cm$ dilated.

  • In teaching hospitals, residents' findings are often verified by more experienced senior residents or attendings.

  • Infection Control: Once the mother's water breaks (rupture of membranes), the number of vaginal exams should be minimized to prevent the introduction of infection, despite patient desire for frequent updates on progress.

Physiological Systems Adaptation

• Cardiovascular System:

  • Blood volume increases significantly above baseline to supply the fetus, placenta, and uterus ($fetal \text{ workload}$).

  • Red blood cell production increases.

  • Hypercoagulable State: Fibrinogen and clotting factors increase to protect the mother against postpartum hemorrhage.

  • Supine Hypotension (Vena Cava Syndrome): A heavy gravid uterus can compress great vessels when the mother lies flat on her back, decreasing perfusion to the baby and causing maternal dizziness. A "tilt" (placing a pillow under the hip) or lying on the left side is recommended.

  • Interventions for Fetal Distress: If fetal heart rates drop (decelerations), interventions include repositioning the mother to her side, administering oxygen, and providing fluids.

• Respiratory System:

  • Breathing becomes diaphragmatic rather than abdominal due to the upward pressure of the uterus.

  • Oxygen consumption increases by $20\%$ to meet fetal demands.

  • Nasal congestion is common due to increased vascularity; saline sprays are the recommended safe treatment.

• Renal and Urinary System:

  • The glomerular filtration rate (GFR) increases by $50\%$

  • Kidneys increase in length and weight.

  • Frequent urination occurs due to increased fluid volume and direct pressure on the bladder (often feeling the urge to pee even with a nearly empty bladder).

• Musculoskeletal System:

  • Softening and stretching of ligaments occurs due to hormonal changes.

  • Lordosis: An exaggerated lower back curve develops to compensate for the forward shift in the center of gravity, increasing the risk of falls.

  • Round Ligament Pain: Sharp, common pains resulting from the stretching of the ligaments as the uterus enlarges.

• Integumentary System:

  • Melasma (Chloasma): Known as the "mask of pregnancy," presenting as facial hyperpigmentation that worsens with sun exposure.

  • Striae Gravidarum: Stretch marks caused by skin stretching and cortisol effects. These are largely genetic; moisturizers may help with appearance, but they generally fade to light marks post-delivery rather than disappearing.

• Endocrine System:

  • Thyroid gland slightly enlarges; Thyroid Stimulating Hormone (TSH) decreases.

  • Insulin resistance typically develops in the second half of pregnancy.

  • Oxytocin: Produced by the posterior pituitary; it is responsible for inducing labor and is used therapeutically in synthetic form to augment labor.

Nutrition and Weight Management

• Folic Acid: Essential for preventing neural tube defects such as Spina Bifida. Ideally, intake should begin before conception.

• Weight Gain Guidelines (Based on BMI):

  • Ideal BMI ($18.5$): Recommended gain of $28$ to $40$ pounds.

  • Higher BMIs require lower weight gain (as low as $15$ to $25$ pounds).

  • Nurses should encourage fiber, fluids, and walking to manage weight and prevent constipation.

• Pica and Cravings: Some mothers experience cravings for non-food items (e.g., dirt, clay, sniffing laundry detergent). Education must be provided without judgment to steer the mother toward proper nutrients.

Intrapartum Considerations and Fetal Positioning

• Fetal Positioning: The goal is a cephalic (head-down) presentation.

• Breech Delivery: When a baby is positioned feet- or buttocks-first. This is a high-risk situation that requires pediatricians and Neonatal Intensive Care Unit (NICU) teams at the bedside for potential resuscitation. The head can become trapped as the cervix clamps down post-body delivery.

• Pushing Technique: Mothers should "bear down" as if having a bowel movement. This often results in defecation during labor, which is a sign of effective pushing technique.

• Tearing vs. Episiotomy:

  • Lubrication is used to minimize tearing.

  • Episiotomy: A surgical cut that is uniform and easier to repair than a spontaneous tear.

  • Spontaneous Tears: Can be irregular and difficult to stitch, sometimes taking hours to repair.

  • Pushing should only occur at the peak of a contraction for maximum efficiency.

Psychological and Family Dynamics

• Maternal Role Attachment ("Binding-In"): An emotional process where the mother develops an attachment to the fetus. This includes mood swings, ambivalence in the first trimester, and introversion as she focuses on bodily changes.

• Body Image: Pregnancy can be challenging for those with histories of eating disorders (anorexia or bulimia) or body dysmorphia. Specialized nutrition consults may be necessary.

• Support for Mothers: Pregnancy is physically and emotionally taxing ("it sucks"); acknowledgment of this by the nurse provides significant support.

• Family-Centered Care: Modern families vary (nuclear, sperm donors, adoptive, etc.). Clinicians must remain non-judgmental even in complex social situations (e.g., multiple partners present).

• Siblings: Hospital policies often require siblings to be $16$ years or older to be in Labor and Delivery. Sibling rivalry is common, and regression to baby-like behavior can occur in older children once the newborn arrives.

Ethics and Advanced Interventions

• Fetal Surgery for Spina Bifida: Programs (such asThose at CHOP) can perform in-utero repairs.

  • Risks to Mother: Requires high-dose Magnesium Sulfate, risk of pulmonary edema, and potential for preterm labor.

  • Ethics: The mother must weigh the risk to her own life and the potential loss of the pregnancy against the benefit to the child's future mobility.

• Breastfeeding Choices: While nurses educate on the benefits of colostrum (especially for premature babies) and breastfeeding, they must respect the mother's right to choose formula or pumping if breastfeeding feels unnatural or undesired.

Questions & Discussion

• Cervical Verification: A student shared an anecdote about being told they were not in labor one day and delivering the next. The instructor explained that it is common to be "preceptive" to labor; the instruction should have been to return if contractions intensified, rather than simply staying home.

• Teenage Education: When educating teenagers on complications like Premature Rupture of Membranes (PROM), the instructor noted the need for very explicit communication (e.g., "the penis and vagina cannot interact") to ensure the message is understood.