Premature Rupture of Membranes Assoc. Prof. Gazi YILDIRIM

Objectives List the history, physical findings, and diagnostic methods to confirm the rupture of the membranes Identify the risk factors for premature rupture of membranes Describe the risks and benefits of expectant management versus immediate delivery, based on gestational age Describe the methods to monitor maternal and fetal status during expectant management

Definition Premature rupture of membranes (PROM) Rupture of the chorioamnionic membrane (amniorrhexis) 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

Risk factors Chorioamnionitis Vaginal infections Cervical abnormalities Vascular pathology (incl. abruptio) Smoking 1st, 2nd, 3rd, or multiple trimester bleeding Previous preterm delivery (PPROM) Ethnicity Acquired or congenital connective tissue disorder Nutritional deficiencies (Vit.C, copper, zinc)

PROM/PPROM: Risk Factors 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

Symptoms Vaginal discharge Gush of fluid Leaking of fluid Oligo/Anhydramnios Cramping Contractions Back pain

Diagnosis Sterile Speculum Exam (Pooling) SSE-Free flow of fluid from cervical os Nitrizine testing Microscopic Fern testing Fetal Fibronectin AmniSure Ultrasonography Transabdominal Indigo dye injection

Diagnosis Latency period Infection Digital Vaqinal exams significantly decrease the latency period in patients compared to those who only received a SSE. In addition, the necessity in doing a digital exam is to determine cervical status, which in Preterm patients rarely alters the POC, unless delivery is imminent. Studies also show an increase in the incidence of infection in patients with PROM who have had a digital exam, especially a higher incidence of neonatal infection in patients who had a digital exam > 24 hrs prior to delivery.

PROM/PPROM: History & Physical Exam “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 (for fetal fibronectin ect.) Findings Pooling of amniotic fluid in posterior vaginal fornix Fluid per cervical os

PROM/PPROM: Diagnosis Test 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

PROM/PPROM: Diagnosis False positive Nitrazine test Alkaline urine Semen (recent coitus) Cervical mucus Blood contamination Vaginitis (e.g. Trichomonas) False-Negative Nitrazine test Remote PROM with no residual fluid Minimal amniotic leakage

PROM/PPROM: Diagnosis AmniSure Detects trace amounts of placental alpha microglobulin-1 protein in vaginal fluid. Newer test Point of Care test Cost-up to $50 each Sensitivity-98.7-98.9% Specificity-87.5-100%

PROM/PPROM: Diagnosis Test 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 Amnisure tests detect trace amounts of placental alpha microglobulin-1 protein in vaginal fluid. Test enhanced to eliminate hook effect which caused false negative results in grossly ruptured patients. Again, once diagnostic tool, Be sure to step back and look at the entire clinical picture.

PROM/PPROM: Management Gestational age Availability of NICU Fetal presentation FHR pattern Active distress (maternal/fetal) Labor? Cervical assessment Amnisure tests detect trace amounts of placental alpha microglobulin-1 protein in vaginal fluid. Test enhanced to eliminate hook effect which caused false negative results in grossly ruptured patients. Again, once diagnostic tool, Be sure to step back and look at the entire clinical picture.

Management: PPROM (< 24 wk gestation – “previable”) Patient counseling Expectant management vs. induction of labor GBS prophylaxis NOT recommended Antibiotics Incomplete data Corticosteriods NOT recommended

Management: PPROM (< 24 wk gestation – “previable”) Patient counseling Fetal complications of prolonged PPROM Pulmonary hypoplasia Skeletal malformations Fetal growth restriction IUFD Maternal complications of prolonged PPROM Chorioamnionitis Gestational Age (In Completed Weeks) Death Before NICU Discharge Outcomes at 18 to 22 Months Corrected Age* Death Death/ Profound Neurodevelopmental Impairment Death/Moderate to Severe Neuro- developmental Impairment 22 Weeks 95% 98% 99% 23 Weeks 74% 84% 91% 24 Weeks 44% 57% 72% 25 Weeks 24% 25% 38% 54%

Management: PPROM (24 – 31 wk gestation) Expectant management Deliver at 34 wks Unless documented fetal lung maturity GBS prophylaxis Antibiotics Single course corticosteroids Tocolytics No consensus

Management: PPROM (32 – 33 wk gestation) Expectant management Deliver at 34 wks Unless documented fetal lung maturity GBS prophylaxis Antibiotics Corticosteroids No consensus, some experts recommend

Management: PROM (> 34 wk gestation) Proceed to delivery Induction of labor GBS prophylaxis

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: Drug Regimen Antibiotics Ampicillin 2 g IV Q6 x 48 hrs Amoxicillin 500 mg po TID x 5 days Azithromycin 1 g po x 1 Corticosteroids Betamethasone 12 mg IM q24 x 2 Dexamethasone 6 mg IM q12 x 4 Tocolytics Nifedipine 10 mg po q20min x 3, then q6 x 48 hrs

Management: Amniocentesis Typically performed after 32 wks Tests for fetal lung maturity (FLM) Lecethin/Sphingomyelin ratio (not commonly used, more for historic interest) L/S ratio > 2 indicates pulmonary maturity Phosphatidylglycerol > 0.5 associated with minimal respiratory distress Flouresecence polarization (FLM-TDx II) > 55 mg/g of albumin Lamellar body count 30,000-40,000 If negative, proceed with expectant management until 34 wks

Management: Surveillance Maternal: Monitor for signs of infection Temperature Maternal heart rate Fetal heart rate Uterine tenderness Contractions Fetal: Monitor for fetal well-being Kick counts Nonstress tests (NST’s) Biophysical profile (BPP)

Management: Surveillance Immediate Delivery Intrauterine infection Abruptio placenta Repetitive fetal heart rate decelerations Cord prolapse

Expectant Management vs. Preterm Delivery Expectant Management Risks: Maternal Increase in chorioamnionitis Increase in Cesarean delivery Spontaneous labor in ~ 90% within 48 hr ROM Increased risk of placental abruption Fetal Increase in RDS Increase in intraventricular hemorrhage Increase in neonatal sepsis and subsequent cerebral palsy Increase in perinatal mortality Increase in cord prolapse