PTL

• Premature labor


  Labor that occurs between 20 weeks to 37 weeks gestation
• Premature labor


  • Characterized by regular uterine contractions that are strong enough to cause significant cervical dilatation and effacement
  • The greatest cause of neonatal mortality, accounting for about 75% of neonatal deaths where no congenital malformation is involved
• Definition of terms

  • Low birth weight (LBW): infant with a birth weight of less than 2,500 g
  • Very low birth weight infant: infant with a birth weight of less than 1,500g
  • Extremely low birth weight: infant with a birth weight of less than 1000g
  • Large for gestational age (LGA): infant with a birth weight above the 90th percentile
  • Appropriate for gestational age: infant with a birth weight between the 10th and 90th percentile
  • Small for gestational age (SGA): infant with a birth weight below the 10th percentile rank
• Risks of premature birth to infants


  • Respiratory distress syndrome (RDS)
  • Pathologic apnea: prolonged cessation of breathing common in preterm below 30 weeks old
  • Infections (necrotizing enterocolitis)
  • Congenital health defects (PDA)
  • Thermoregulation problems
  • Feeding difficulties d/t diminished stomach capacity and underdeveloped sucking reflex
  • Neurological d/o r/t hypoxia and trauma birth
  • Anemia
  • Jaundice d/t immaturity of the liver and GIT
• Causes/Risk factors of premature labor

  • Etiology is unknown
  • A previous hx of PTL with an early delivery: labeled as the greatest risk fx for premature birth
  • One or more spontaneous second-trimester abortions: major risk
  • Epidemiological factors: Low socioeconomic status, Low pre-pregnant weight, Early and late pregnancy, Non white race, Maternal smoking, Use of cocaine, Stressful living conditions, Job that requires physical labor, Teenage primigravida, Multiparity
  • Overdistention of the uterus caused by multiple pregnancy and hydramnios
  • Uterine abnormalities: unicornuate/bicornuate uterus, Fibroid tumors, Cervical incompetence, Previous uterine surgery, Shorter cervix
  • Maternal infections: STD, Untreated acute pyelonephritis, Bacterial vaginosis, Exposure to DDT, DES (Diethylstilbestrol)
  • Serious maternal conditions: Chronic hypertension, Diabetes, Poor maternal nutrition
  • PROM
  • Infection of amniotic fluid
  • Congenital malformation of the fetus and placenta
  • Fetal death
  • Abnormal placentation: placenta previa, abruption placenta
  • Retained IUD
  • Complication of pregnancy that requires immediate delivery of the fetus regardless of gestational age
  • Unknown causes: almost half of the causes of premature labors are unknown
• Signs and symptoms of premature labor

  • Diagnosis is made when there is regular uterine contractions occurring 5-8 minutes apart accompanied by progressive cervical changes, cervical dilatation of more than 2 cm, cervical effacement of 80% or more, duration of at least 30 seconds
  • Menstrual like cramping, Water or bloody vaginal discharge, Low back pain, Intestinal cramps with or without diarrhea, Pelvic pressure due to descent of fetus
• Management of premature labor

  1. Prevention: regular prenatal check up, Prenatal screening, Pt. high risk for PTL- first approach is education of pt regarding preterm labor, Lifestyle modification, Instruct for the s/sx of PTL, Teach pt how to palpate contractions, Contact HCP to report any s/sx, Inform about the effects of preterm birth: high morbidity and mortality

  2. Biochemical markers of PTL: Fetal fibronectin enzyme, Salivary estriol - greater than 2.1 ng/ml is a positive result

  3. When preterm labor occurs, attempt to stop contractions is made if the fetus is less than 32 weeks: Bedrest- left lateral, Hydration, Non-stress test- to evaluate fetal well being, Tocolytics: ritodrine hydrochloride (SE: hypotention, tachycardia, arrhythmia, Antidote: propanolol), Other drugs: MgSO4, Terbutaline, Prostaglandin inhibitors (indomethacin), Isosuxiprine hydrochloride (isoxilan), Salbutamol, fenoterol, hexaprenaline, Drugs that hasten fetal lung maturity: Bethamethasone

  4. Home Management: Prenatal visit weekly, Bedrest, Avoid fatigue, Abstinence from sexual activity, Proper hydration, Stop smoking and alcohol drinking, Tocolytic tx, Home uterine activity monitoring

  5. If delivery cannot be prevented: Sedative and analgesics are kept to minimum to prevent respiratory distress, Cord is cut immediately