
Preterm labor and PROM • Dr. Wisit Woranitat
Preterm labor • What is preterm labor • How dose labor start • What can happen if my baby is born too early • What factors increase the risk of preterm labor • What are the signs and symptoms of preterm labor • How can preterm labor be diagnosed
Preterm labor • If I am at risk of preterm labor, what can I do to decrease the risk • How do I monitor myself for contraction • What medications are used to slow or stop per term • What are the special needs of preterm babies
What is preterm labor • The labor begin start before 37 weeks • About 1 in 10 babies born in USA • 75% of neonatal mortality • 50% of the long term neurologic impairment in children
How does labor start • Regular uterine contraction • Progression of cervix • Effacement • Dilatation • Hormones produced by uterus and placenta
What can happen if my baby is born too early • Newborn death • Eyes • Ears • Breathing • Nervous system
Perinatal Morbidity • Pulmonary- RDS bronchopulmonary dysplasia • Cardiovascular: PDA, persistent fetal circulation • CNS: IVH, cerebral palsy, seizures, sensory deficits • GI: NEC • Metabolic: hypoglycemia, hypocalcemia, jaundice
Perinatal morbidity • Infections: GBS, E. Coli • SIDS • Psychosocial:> prevalence of child abuse
Pathogenesis • 80% of Preterm births are spontaneous • 50% Preterm labor • 30% Preterm premature rupture of the membranes • Pathogenic processes • Activation of the maternal or fetal hypothalamic pituitary axis • Infection • Decidual hemorrhage • Pathologic uterine distention
How can preterm labor be diagnosed • Cervical change • Regular contraction • Ultrasonography. ( Cx length ) • Fetal fibronectin • Fetal mornitoring
Biologic markers for predicting preterm birth • Cervical length measurement- many studies have confirmed an association with cervical shortening and preterm delivery. When combined with positive fetal fibronectin and length less than 2.5 cm, this is a strong predictor of preterm delivery
Biologic markers for predicting preterm birth • Fetal fibronectin- need intact membranes, less than 3 cm dilated, not useful before 24 weeks or after 34 weeks 6 days • Negative fetal fibronectin gives about a 95% chance of the pregnancy continuing 14 days or more. A positive test is not as predictive.
What can I do to decrease the risk of preterm labor • Early ANC • Test or investigation • Progesterone • Limited and control the risk
How do I monitor myself for contraction • Monitor for sign of uterine activity • 4 times in 20 minutes • 8 times in 60 minute • Vaginal discharge • PROM
What medications are used to slow or stop preterm • Tocolysis agents • Corticosteroid • Anti-biotic agent
Assessment of patients in preterm labor • Labs-CBC, UA +/- culture, electrolytes • Sterile speculum exam obtaining cultures for group B strep, BV, GC, Chlamydia, obtain fetal fibronectin • Cervical length measurement • The last thing is the cervical digital exam
What are the special needs of preterm babies • NICU • Breathe • Eat • Keep warm • Other health problem
Premature rupture of membrane • Definition • Incidence • Diagnosis • Risk factors • Management
Definition • Premature rupture of membranes (PROM) • Rupture of the chorioamnionic membrane prior to the onset of labor at any stage of gestation • Preterm premature rupture of membranes (PPROM) • PROM prior to 37-wk. gestation
Incidence • PROM – 12% of all pregnancies • PROM – 8% term pregnancies • PPROM – 30% of preterm deliveries
Diagnosis • History • “Gush” of fluid • Steady leakage of small amounts of fluid • Physical • Sterile vaginal speculum exam • Minimize digital examination of cervix, regardless of gestational age, to avoid risk of ascending infection/amnionitis • Assess cervical dilation and length • Obtain cervical cultures (Gonorrhea, Chlamydia) • Obtain amniotic fluid samples • Findings • Pooling of amniotic fluid in posterior vaginal fornix • Fluid per cervical os
Diagnosis • Test or investigation • Nitrazine test • Fern test • Nine blue test • Ultrasound • Indigo-carmine Amnioinfusion
Nitrazine test • Fluid from vaginal exam placed on strip of nitrazine paper • Paper turns blue in presence of alkaline (pH > 7.1) amniotic fluid
Fern test • Fluid from vaginal exam placed on slide and allowed to dry • Amniotic fluid narrow fern vs. cervical mucus broad fern
Nile blue tests • >32 wks. Fetal fat cell can discover in amniotic fluid • Strained with Nile blue sulphate. Become to red color
Fetal Fibronectin (AmniSure) • Newer test • Point of Care test • Cost-up to $50 each • Sensitivity-98.7-98.9% • Specificity-87.5-100% • Awaiting further testing prior to recommendations
Ultrasound • Assess amniotic fluid level and compatibility with PROM • Indigo-carmine Amnioinfusion • Ultrasound guided indigo carmine dye amnioinfusion (“Blue tap”) • Observe for passage of blue fluid from vagina
Risk factor of PROM • Prior PROM or PPROM • Prior preterm delivery • Multiple gestation • Polyhydramnios • Incompetent cervix • Vaginal/Cervical Infection • Gonorrhea, Chlamydia, GBS, S. Aureus • Antepartum bleeding (threatened abortion) • Smoking • Poor nutrition
Effect to mother and fetus • Feto-maternal infection • Placenta abruptio • Premature infant: 30% - 40% of premature labour is associated with premature rupture of membrane • Cord prolapse, cord compression • Poor fetal lung development and fetal compression syndrome
Management PROM at term: (1) Awaiting the onset of spontaneous labor for 12-24h (2) Termination of pregnancy after 24 hours
PROM before term Termination of pregnancy (1) Evidence of fetal pulmonary maturation (2) Evidence of intrauterine infection Expectant therapy Indication : (1) Evidence of fetal pulmonary immaturation (2) Without evidence of intrauterine infection Management: (1)To enhance fetal pulmonary maturation (2) Antibiotic (3) Tocolysis
Management: Rationale • Antibiotics • Prolong latency period • Prophylaxis of GBS in neonate • Prevention of maternal chorioamnionitis and neonatal sepsis • Corticosteroids • Enhance fetal lung maturity • Decrease risk of RDS, IVH, and necrotizing enterocolitis • Tocolytics • Delay delivery to allow administration of corticosteroids • Controversial, randomized trials have shown no pregnancy prolongation
Management: Surveillance • Maternal: Monitor for signs of infection • Temperature • Maternal heart rate • Fetal heart rate • Uterine tenderness • Contractions
Management: Surveillance • Fetal: Monitor for fetal well-being • Kick counts • Nonstress tests (NST’s) • Biophysical profile (BPP) • Immediate Delivery • Intrauterine infection • Abruptio placenta • Repetitive fetal heart rate decelerations • Cord prolapse.
Thank you • For your attention