This document discusses premature rupture of membranes (PROM), including definitions of term PROM (rupture at or after 37 weeks) and preterm PROM (rupture before 37 weeks). It provides information on risk factors, diagnosis, management, and treatment recommendations depending on gestational age. For term PROM, induction of labor is usually recommended. For preterm PROM between 24-33 weeks, expectant management with antibiotics is preferred to prolong the pregnancy if possible. Delivery is recommended for preterm PROM at or above 34 weeks.

1. Premature rupture of
membranes
Dr. HANI MAHDI
Dec. 2017

2. Premature rupture of membranes at term
(term PROM)
• rupture of chorioamniotic membranes ≥ 1 hour prior to onset of labor at
37 weeks gestation or beyond
• Also called:
• term PROM
• prelabor rupture of membranes
• Definitions
• term premature rupture of membranes - premature rupture of membranes
after 37 weeks gestation
• Incidence/Prevalence
• reported in 8% of term deliveries

3. Preterm premature rupture of membranes
(PPROM)
• rupture of chorioamniotic membranes ≥ 1 hour prior to onset of labor in
pregnancy prior to 37 weeks gestation
• Also called
• preterm PROM
• preterm prelabor rupture of membranes
• Definitions
• preterm premature rupture of membranes (PPROM) - premature rupture
of membranes before 37 weeks gestation
• premature rupture of membranes at term (term PROM) - premature
rupture of membranes after 37 weeks gestation

4. Epidemiology
• most cases of premature rupture of membranes occur in women
without identifiable risk factors
• Incidence/Prevalence
• 3% of all pregnancies in United States
• about 2% of all pregnancies in United Kingdom, including about 40%
of preterm deliveries

5. Risk factors
• obstetrical factors
• prior history of premature rupture
of membranes - risk of recurrence
16%-32%
• intra-amniotic infection
• amniocentesis
• second- and third-trimester
bleeding
• cervical cerclage
• cervical length < 25 mm in second
trimester
• uterine overdistention
• nonobstetrical factors
• low socioeconomic status
• smoking
• body mass index < 19.8 kg/m2
• connective tissue disorders
• pulmonary disease in pregnancy
• nutritional deficiencies of copper
and ascorbic acid
• Chlamydia trachomatis infection

6. Possible risk factors
• uterine synechiae associated with increased risk of placental
abruption, preterm premature rupture of membrane, and cesarean
delivery for malpresentation
• subchorionic hematoma associated with increased risk of pregnancy
loss, stillbirth, placental abruption, preterm delivery, and preterm
premature rupture of membranes
• low preconception vitamin C intake (< 10th percentile)
• occupational fatigue

7. History
• Chief concern (CC)
• fluid passing from vagina
• patient history 90% sensitive for PPROM
• History of present illness (HPI)
• ask about
• preterm labor
• second- and third-trimester bleeding
• cervical cerclage

8. Physical
• General physical
• assess for elevated temperature > 38 degrees C with chorioamnionitis
• tachycardia may be present (maternal and fetal) with chorioamnionitis
• Abdomen
• assess size and presentation with fundal height measurement and Leopold maneuver
• Pelvic
• avoid digital exam for patients not in active labor
• on sterile speculum exam look for
• pooling of fluid
• leakage of fluid from cervical os
• cervical effacement and dilatation (visual assessment)
• evidence of cervicitis
• umbilical cord prolapse
• obtain fluid from posterior fornix for evaluation of
• pH with Nitrazine paper (amniotic fluid usually has pH 7.1-7.3 and turns Nitrazine paper blue)
• ferning
• uterine tenderness may indicate chorioamnionitis

9. Diagnosis
• Royal College of Obstetricians and Gynaecologists (RCOG) recommendations
• diagnosis should be made based on maternal history followed by sterile speculum examination
• ultrasound may be used if needed to confirm diagnosis
• avoid digital exam if PPROM suspected unless strong suspicion of labor
• tests on pooled vaginal fluid
• Nitrazine paper
• positive for amniotic fluid if dark blue
• amniotic fluid pH 7.1-7.3, while urine and vaginal secretions usually acidic (< 7)
• false positives with blood, semen, alkaline antiseptics, or bacterial vaginosis
• false negatives may occur with prolonged membrane rupture and minimal residual fluid
• fern test - let amniotic fluid dry on glass slide
• positive if microscopy reveals fern pattern with multiple fine branches
• cervical mucus can cause false positive
• significant blood can cause false negative
• unaffected by pH
• ultrasound not diagnostic but assessing amniotic fluid volume may aid in diagnosis(

10. Differential diagnosis
• mucous "show" with cervical effacement and dilatation
• discharge from vaginitis or cervicitis
• urinary incontinence
• semen
• vaginal douches

11. Initial testing
• fetal heart rate monitoring
• ultrasound for gestational age, presentation, amniotic fluid index
• cervical cultures for gonorrhea and chlamydia if indicated
• anovaginal cultures for group B Streptococcus
• amniocentesis considered unnecessary for diagnosis of intrauterine
infection
• transabdominal instillation of indigo carmine dye if diagnosis
unclear after full evaluation

12. Initial testing
• monitor for maternal signs of intrauterine infection
• consider maternal temperature checks every 4-8 hours
• tests considered unnecessary for diagnosis of intrauterine infection
include
• weekly high vaginal swab
• weekly maternal full blood count
• C-reactive protein
• amniocentesis

13. Other diagnostic testing
• placental alpha-microglobulin-1 immunoassay (PAMG-1) (AmniSure):
• PAMG-1 had sensitivity 96.9% and specificity 98.5%
• placental alpha-microglobulin-1 immunoassay results available in 5
minutes
• commercially available absorbent pad (AmnioSense) can rule out
ruptured membranes
• The Vision Amniotic Leak Detector (ALD; CommonSense Ltd) is a non-
invasive diagnostic panty liner that can be attached to underwear. The
panty liner has a central polymer-embedded strip that turns blue-green on
contact with fluid that has a pH higher than 5.2 (normal vaginal pH is 3.5 to
4.5 and amniotic fluid has a pH of 6.5 or above).

14. Performance of Placental Alpha Microglobulin-1
Protein Assay in Diagnosis of ROM

15. Other diagnostic testing
• The claimed benefits of Vision ALD in the case for adoption presented by
the sponsor are:
• A reduction in unnecessary speculum examinations.
• A reduction in the time spent in hospital.
• A reduced risk of infection from speculum examination, particularly if
repeat examinations are required.
• The incidental detection of possible vaginal infection.
• A reduction in the costs associated with the avoidance of speculum
examination.
• A reduction in staff time and hospital bed use.

16. Management of PROM after 37 weeks
• routine monitoring
• delivery recommended
• labor should be induced at time of presentation, usually with oxytocin
IV infusion or by misoprostol
• 50% of women with PROM at term managed expectantly will deliver
within 5 hours and 95% within 28 hours
• routine antibiotic administration not recommended for women with
premature rupture of membranes (PROM) at or near term

17. Treatment
• digital cervical examinations should be avoided unless patient in
active labor or imminent delivery anticipated
• recommended management based on gestational age and
assessment of fetal status
• for PPROM at ≥ 34 weeks gestation
• delivery recommended
• labor should be induced, usually with oxytocin IV infusion
• group B streptococcal prophylaxis is indicated based on prior culture
results if available; if culture results not available, provide prophylaxis
since < 37 weeks gestation

18. Treatment
• PPROM at 24-33 weeks gestation
• if pulmonary maturity not proven, expectant management preferred until
33 completed weeks gestation
• 48-hour treatment with IV ampicillin and erythromycin followed by 5 days
of amoxicillin and erythromycin recommended to prolong latency if no
contraindications
• single course of corticosteroids recommended
• intrapartum group B streptococcal prophylaxis recommended if fetus viable
• consider magnesium sulfate IV for fetal neuroprotection if risk of imminent
delivery in women before 32 weeks gestation
• in setting of PPROM with active labor, therapeutic tocolysis not
recommended
• expectant management at home not recommended

19. Antibiotic Therapy in PPROM

20. Treatment
• expectant management if no maternal or fetal contraindications exist:
• modified bed rest to facilitate reaccumulation of amniotic fluid
• complete pelvic rest
• periodic assessment for:
• evidence of infection
• reassuring fetal status
• umbilical cord compression
• placental abruption
• onset of labor

21. Treatment
• for PPROM at < 24 weeks gestation (periviable)counsel regarding risks and
benefits, including likely neonatal morbidity and mortality, comparing
immediate delivery vs. expectant management based on most current data
• group B streptococcal prophylaxis not recommended
• consider hospital admission for
• bed rest and strict pelvic rest to increase chance of resealing amniotic
membrane
• monitoring for infection or placental abruption
• ongoing monitoring once pregnancy has reached viability
• corticosteroids may be considered for PPROM as early as 23 weeks
gestation if increased risk of preterm delivery

22. Royal College of Obstetricians and
Gynaecologists (RCOG) guideline
• recommended treatmentserythromycin should be given for 10 days
following the diagnosis of PPROM
• if group B Streptococcus is isolated in cases of PPROM, antibiotics
should be given based on recommendations for routine intrapartum
prophylaxis
• antenatal corticosteroids should be given to women with PPROM
• delivery should be considered at 34 weeks gestation
• if expectant management considered after 34 weeks gestation,
women should be counseled about increased risk of chorioamnionitis
and decreased risk of respiratory problems in the neonate

23. Royal College of Obstetricians and
Gynaecologists (RCOG) guideline
• therapeutic treatments not recommended
• amoxicillin-clavulanate not recommended for women with PPROM
due to increased risk for necrotizing enterocolitis
• tocolysis not recommended in women with PPROM
• amnioinfusion during labor not recommended for women with
PPROM
• transabdominal amnioinfusion not recommended as a method of
preventing pulmonary hypoplasia in very preterm PROM
• fibrin sealants not recommended as routine treatment for second-
trimester oligohydramnios caused by PPROM

24. Delivery and induction
• for PPROM at ≥ 34 weeks gestation delivery recommended and labor
should be induced
• if expectant management continued beyond 34 weeks gestation
• discuss risks and benefits with patient
• expectant management should not extend beyond 37 weeks gestation
• delivery should be considered
• Medications for labor induction
• oxytocin generally used for induction of labor for women ≥ 34 weeks
gestation
• misoprostol appears comparable to oxytocin for induction of labor in
women with PPROM

25. Cerclage removal
• recommendation for either cerclage removal or retention cannot be
made
• if cerclage retained, antibiotic prophylaxis ≥ 7 days not recommended
• retention and removal of cerclage might be similar for prolonging
pregnancy, but retention might increase rate of infection in women
with PPROM

26. Complications
• maternal complicationsinfection
• chorioamnionitis - clinically evident infection in about 15%-25%
• presence of cerclage in patients with PPROM associated with increased risk for
chorioamnionitis
• postpartum infection in about 15%-20%
• placental abruption
• fetal/neonatal complications
• umbilical cord compression
• preterm delivery with neonatal complications due to prematurity
• respiratory distress syndrome
• necrotizing enterocolitis
• intraventricular hemorrhage of infancy
• sepsis
• if < 22 weeks - fetal pulmonary hypoplasia

27. Prognosis
• pre-viable PPROM occurs in < 1% pregnancies
• latency periods (time until onset of spontaneous labor) and
gestational age
• decreased neonatal death and morbidity associated with increasing
gestational age and longer latency period
• increasing gestational age at membrane rupture associated with decreased
latency period
• latency period may be longer in women with second-trimester PPROM than
with PPROM at later gestational ages
• typical latency period in women with PPROM
• 40%-50% will deliver within 1 week of membrane rupture
• 70%-80% will deliver within 2-5 weeks of membrane rupture

28. Prognosis
• reasons for preterm births
• 7.4% preterm premature rupture of membranes (PPROM)
• 39% indicated preterm births
• 53.6% spontaneous preterm labor

29. Prevention
• vitamin C supplementation may reduce risk of premature rupture of
membranes (PROM)
• antibiotic prophylaxis during second and third trimester of pregnancy
may not reduce risk of PPROM

30. Lung Maturity
• Pulmonary surfactant is synthesized by type II pneumocytes. Surfactant
consists of 90% phospholipids (primarily phosphatidylcholine and
phosphatidylglycerol) and 10% proteins (surfactant proteins [SP]-A, SP-B,
SP-C).
• Surfactant is packaged into lamellar bodies and is excreted into the
alveolar space where it unravels and forms a monolayer on alveolar
surfaces.
• The surfactant functions to reduce the surface tension in the alveoli,
preventing atelectasis.
• Tests for fetal lung maturity are generally not performed before 32 weeks
of gestation, given the high prevalence of fetal pulmonary immaturity and
the lower predictive value of a mature test result at this gestational age.
• Tests for fetal lung maturity are not performed in pregnancies with a
reliable gestational age ≥39 weeks.

31. Lamellar body count
• lamellar body number density (LBND) assessment
• A standard hematology analyzer can be used for quantification
because of the similar size of lamellar bodies and platelets.
• Normal ranges have been developed and depend on the individual
laboratory (maturity ≥ 46,000 µL LBND), and the sensitivity
and predictive value are as good if not better than the standard L/S
ratio
• Blood contamination can lead to false elevation of the lamellar body
count because platelets are counted as lamellar bodies; the effect of
meconium is minimal.

32. Phosphatidylglycerol
• Phosphatidylglycerol (PG) is a minor constituent of surfactant. It begins to
increase appreciably in amniotic fluid after 35 weeks, several weeks after
the rise in lecithin.
• Because PG enhances the spread of phospholipids on the alveoli, its
presence indicates an advanced state of fetal lung development and
function
• PG testing may be reported qualitatively as positive or negative, where
positive represents an exceedingly low risk of respiratory distress, or
quantitatively, where a thin-layer chromatography value >2 percent is
associated with a minimal rate of respiratory distress
• Blood or meconium usually does not affect test results
• Bacteria can give a false positive in vaginal pool samples.

33. Lecithin/sphingomyelin ratio
• First introduced by Gluck and colleagues in 1971
• It is based upon the observation that there is outward flow of lung
secretions from the lungs into the amniotic fluid.
• The concentrations of lecithin and sphingomyelin in amniotic fluid are
approximately equal until 32 to 33 weeks of gestation, at which time the
concentration of lecithin begins to increase significantly while the
sphingomyelin concentration remains about the same. The measurement
of sphingomyelin serves as a constant comparison for control of the
relative increases in lecithin because the volume of amniotic fluid cannot
be accurately measured clinically.
• The risk of respiratory distress is exceedingly low when the
lecithin/sphingomyelin ratio is greater than 2.0
• It takes several hours to perform the test

34. LUNG PROFILE
• Both PG and PI along with the L/S ratio make up the lung profie.
• RDS is rare when the L/S ratio is greater than 2 and PG is present, whereas
when the L/S ratio is less than 2 and no PG is present, more than 90% of
infants will develop RDS.
• If the L/S ratio indicates pulmonary immaturity (L/S < 2) but PG is
present, fewer than 5% of infants develop RDS.
• The lung profie offers a more reliable predictor of pulmonary maturity,
especially in infants of diabetic mothers.
• Other advantages of using PG are that contamination with vaginal
secretions or blood, as occurs in cases of ruptured membranes and vaginal
pool sampling, does not interfere with its detection.

35. Optical density at 650 nm
• An indirect measurement of lamellar bodies can be obtained by
measuring the optical density of amniotic fluid at a wavelength of 650
nanometers.
• It is based upon the concept that increasing opalescence is due to
increasing numbers of lamellar bodies.
• An optical density reading ≥0.15 is used as the indicator of lung
maturity

36. Foam stability index
• based upon the ability of surfactant to generate stable foam in the
presence of ethanol
• Ethanol is added to a sample of amniotic fluid to eliminate the effects
of nonsurfactant factors on foam formation. The mixture is then
shaken and will generate a stable ring of foam if surfactant is present.
The FSI is calculated by utilizing serial dilutions of ethanol to
quantitate the amount of surfactant present
• The discriminating value indicative of lung maturity is usually set at
≥47.

37. The Fetal Lung Maturity test
• The Fetal Lung Maturity test (FLM test, Abbott Laboratories, Irving,
TX) is a test for total surfactant.
• A value of 70 or greater is considered mature.

38. Bedside tests
• The “tap test” and. To perform the “tap test” mix 1 ml of amniotic fluid
with one drop of 6N hydrochloric acid and 1.5 ml of diethyl ether.
The tube containing this mixture is tapped three or four times, creating 200
to 300 bubbles in the ether layer.
• Fluid from a mature fetus causes the bubbles to break down rapidly. If no
more than five bubbles persist in the ether layer after 10 minutes, the
result is considered mature.
• Faster disappearance of bubbles provides more assurance of lung
maturity.
• The turbidity test: a tube of amniotic fluid is held over newsprint. If the
fluid is turbid enough to prevent the reading of newsprint, fetal lung
maturity is predicted with 97 percent certainty