PRETERM BIRTH (PARTUS PREMATUR) (Part one)

Diagnosis

1. Medical History
   • Past preterm births, current uterine contractions.
   • Infections during pregnancy and symptoms of current infections (urinary, respiratory).
   • Sexual activity, heavy physical exertion, trauma, various medications.
2. Physical Examination
   • General (temperature, fetal or maternal tachycardia).
   • Vaginal examination with a speculum (excluding membrane rupture and taking culture for chlamydia, gonorrhea, group B streptococcus, trichomonas, bacterial vaginosis, mycoplasma hominis, and ureaplasma urealyticum).
   • Bimanual vaginal examination after excluding membrane rupture.
3. Laboratory Analysis
   • Complete blood count, complete urine and urine culture, vaginal swab, and culture of vaginal secretions.
   • Fetal fibronectin.
4. Ultrasound

   Evaluation: fetal position, amniotic fluid, approximate fetal weight, fetal and uterine anomalies, fetal biophysical profile, placenta localization and structure, signs of placental abruption.

5. Continuous monitoring of fetal heart rate (FHR) and uterine contractions.

How to evaluate uterine contractions:

• Place a hand on the abdomen.
• If we feel the uterus begins to strengthen, then we are dealing with uterine contractions.
• Evaluate the duration of a uterine contraction and their frequency.
• Relieve uterine contractions (sit or lie down, fold legs, change position, drink 2-3 glasses of water).
• Irregular, infrequent contractions are false contractions and do not cause changes in the cervix and are Braxton-Hicks contractions.

Risk assessment during pregnancy

Obstetric history, high risk in women with a previous history of preterm birth.

Physical assessment, bimanual and speculum vaginal examination which evaluates whether there is a rupture of membranes or not and the changes observed in the cervix in relation to dilation and shortening. Cervical length less than 25mm, in pregnancy under 28 weeks has a sensitivity of up to 49% for preterm birth.

Laboratory tests, assessment for symptomatic and asymptomatic bacterial vaginosis, sexually transmitted diseases like gonorrhea, chlamydia, vaginal pH, vaginal swab, pap test, glucose tolerance test, TORCH IgM and IgG, Anti-cardiolipin antibodies, Lupus anticoagulant antibodies.

Fetal Complications:
• respiratory distress syndrome
• bronchopulmonary dysplasia
• patent ductus arteriosus
• necrotizing enterocolitis
• neurological damage
• apnea
• neonatal sepsis
• fetal death

Premature children later have a higher risk for pulmonary problems, vision, hearing...

Prognosis

Fetal viability depends on the weeks of pregnancy. The earlier the birth, the higher the risk for fetal mortality. Less than 23 weeks, mortality risk 0-8%, 24 weeks reaches 15-20%, 25 weeks reaches 50-60%, 26-28 weeks reaches up to 85% and 29 weeks reaches up to 90%.

Treatment Objective
• Identification of risk factors for preterm birth
• Timely diagnosis
• Identification of etiology
• Assessment of fetal well-being
• Provision of prophylactic therapy to prolong pregnancy and to reduce the incidence of respiratory distress syndrome and intraamniotic infections
• Initiation of tocolytic therapy when indicated
• Evaluation of a plan for maternal and fetal follow-up
• Premature rupture of membranes

Treatment

1. Hydration. Isotonic solution 500cc iv is administered.
2. Medication to calm the uterus (tocolytic therapy).
   • Prostaglandin synthesis inhibitor, Indomethacin (side effect oligohydramnios).
   • Beta-adrenergic agent, Ritodrine (side effects palpitations, pulmonary edema, myocardial ischemia, arrhythmia).
   • MgSO4 (toxic effects monitored, pulmonary depression, cardiac arrest. Its side effects are flushing, nausea, headache, fatigue).
   • Calcium channel blocker, Nifedipine (side effects hypotension, tachycardia, flushing, weakness, nausea, nasal congestion, intestinal disorders, nervousness).
3. Medication for pulmonary lungs

   Corticosteroids are the medications that promote fetal lung maturation in pregnancy between weeks 24-34, if there are no signs of infection. They accelerate the production of surfactant in the lungs and reduce fetal mortality, cerebral hemorrhage, and necrotizing enterocolitis. Betamethasone can be used twice from 12mg within 24 hours. The optimal effect is achieved after 24 hours from the second dose and lasts up to 7 days.

4. Prophylactic antibiotic therapy

   Used against group B streptococcus, administered in hospital conditions. Penicillin or ampicillin is used. In case of allergy to penicillin, clindamycin is used.

Prevention
• Bed rest
• Reduce physical activity
• Sexual activity is discontinued (there are no solid studies on this)
• Tocolytic therapy is used