Preterm Labour and Preterm Rupture of Membranes

ByProf . Farouk Abdel Aziz

Preterm labour & premature Rupture of Membranes

•OBJECTIVES: •Define PTL and PMROM & describe their

signficance•List risk factors associated with PTL & PROM

•Ouline initial evaluation of of PTL & PROM•Describe management of PTL &PROM

•Discuss neonatal GBS prevention strategies

Preterm Labour

•-Incidence; • 11.6 % of all deliveries

• Rate increasing since 1980

•Definition • Uterine contractions >3in 30 minutes

• Presence of cervical change • Before 37 weeks of gestation

•

Risk factors in PTL

•History: •-Previous PTL•-Maternal age

•-Race•-Uterine anomalies

•Trauma

Risk factors in PTL

•-Current pregnancy:• -maternal infections

• bacteriuria • pyelonephritis

• genital tract • pneumonia

•-Preterm PROM•-Uterine distension –twin ,polyhydramnios

Prevention in high risk groups

•1.Educational programmes •2.Uterine activity management

•3.Assessment of cervicaal length –US •4.Screening and treating BV

• documented reduction in preterm birth

PROM

•-Rupture of membranes at least 1hr before ROMs

•-2-17 % of pregnancies (average 8% )•-20-40 % before 37 ws

•-Precise aetiology unknown: • multiple risk factors

• Infection often plays a role

Patient History

•-detailed history of labour •-history of fluid leakage

•-review history for risk factors •-history of other medical conditions

•-assessment of social history and home support

Physical Examination

•-Maternal vital signs – signs of infection•-Foetal heart rate pattern

•-Uterine contraction pattern•-Foetal size and presentation

•No digital cervical examination if membrane rupture is suspected

Sterile Speculum Examination

•-•Assess for membrane rupture:

•--pooling of fluid in vagina :Fern test & nitrazine •-assess cervix visually

•-Obtain cervical cultures •-Obtain wet prep for vaginitis

•-Obtain GBS culture of other vagina and rectum

Additional Tests

•-CBC ,urinalysis – assess for maternal infection•-Amniocentesis-

• assess foetal lung maturity•-Ultrasound:

• assess amniotic fluid index • determine gestational age - +/- 3 weeks

•-Transvaginal scan for cervical length•-Cervicovaginal swab for foetal fibronectin

Management of PTL

•Consider following factors: • -condition of foetus

•-imminence of delivery •-availability of local resources

•-availability of safe transport to referral centre•-Maternal transport <32-34 weeks decreases

neonatal mortality by 60 % •-Treat underlying conditions

•Bed rest and hydration ? benifit

Corticosteriods in PTL

•-Effectively reduces RDS and infant mortality at 24-34 ws of gestation

•-Betamethasone 12 mg IM 2 doses q 24 hrs •-Dexamethasone 6 mg ,4 doses q 12 hrs

Tocolytics

• -No evidence of long term suppression of labour

•-can be effective for 24-48hrs– • allows time for maternal transfer or

administration of corticsteriods

Candidates for Tocolytics

•-No contra-indication to drugs •-No contra-indication to prolonging

pregnancy•-Foetus currently healthy

•-Clear diagnosis of PTL•-Cervix < 4 cm dilated

Drugs

•-Terbutaline –available in IV,SQ or PO•-ritodrine-only in IV

•-Beta-Agonist cause palpitations ,chest pain ,anxiety,trmor nausea pulmonary oedema and also foetal tachycardia

•Magnesium sulphate

Emperic use of antibiotics

•In PTL with intact membranes-: •- conflicting results in delaying preterm

labour•- No short or long term benefits

demonstrated

Preterm Rupture of Membranes

•-Mangt depends on gestation age ,foetal size & lung maturity

•-Foetus >36 ws or >2500 gm ,manage as term PROM

•-Foetus <36 ws or <2500 gm PROM•-Foetus 32-36 ws :clinical judgement

• consider amniocentesis for lung maturity

PROM

•-Delivery likely within 12-24 hrs • + consult with perinatologist

•+ Plan site of delivery• + Tocolytics and /or corticosteriods

•+ Antibiotics for group B streptococci•+ Avoid digital vaginal examinations

Term Prom

•-Expectant mgt if delivery not imminent: • + No digital exam unless labour begins

• + Follow for signs of ifnection•+ Corticosteriods if foetus is 24-34 ws

•+ Antibiotics controvercial in prolonging latency

Continued

•-Expectant mgt vs induction•+ 90 % spontaneous labour within 48 hrs

•+ induce if signs of infection•+ prostaglandins if cx unfavouable

•-Early oxytocins decreases infection rate without increasing CS delivery rate

Delivery of the Premature Foetus

• *Limit maternal narcotics

•*Anticipate malpresentations

•*Alert neonatal care team of impending delivery

Newborn Management

•*Look for symptoms of sepsis•*Full sepsis evaluation and antibiotics

•*Baby asymptomatic & >35 ws: • - intrapartum antibiotics < 4 hrs

•- limited sepsis evaluation ,CBS,blood culture close observation for at least 48 hrs