Preterm Labor

Audace NIYIGENAIntern in Gynecology & Obstetrics

In Butare University Teaching HospitalSupervised by

Dr Ntwali NDIZEYE

ObjectivesDefine preterm laborDiscuss epidemiologyReview risk factorsDiagnosis Review complicationDiscuss Management

Case studyM.E 19y Admitted on 19th Jan. 2013Transferred from Nyanza DH

Nifedipine 20mg bidDexametasone 12mg 2times

SymptomsPeriodic pelvic pain and back pain for 2 daysNo bleeding, no fluid gush

G.O G1P0Lmp 12th Jull. 2012 GA 27W2D

Case study cntMhx:

No hx of STINo diseases on pregnancyNo asthmaticHIV negNo alcoholNo tobaccoNo trauma

Low socio economic status

Case study cntP/E

HEENT: no pallor, no oedema, no jaundiceChest: good symmetric chest expansion, lung

clear, S1 & S2 well audible without added sound

Abdomen & pelvic: Gravid uterus FH: 24cm Bcf: 148b/m Cephalic presentation 2 contractions/10m Cervix dilatation 4cm Effacement 100% Engagement 1/5

Diagnosis: Preterm labor

Case study cntSpontaneous rupture of membrane at 13h15’14h45’

Eutocic delivery of preterm babyAPGAR 3, weight:900grTransferred in neonatology (but died in the

evening)

Define preterm labor

Term pregnancy - 37 to 42 weeks gestationPreterm pregnancy 24 to 37 weeks gestationPreterm labor is occurrence of uterine

contractions between 24 to 37 weeks of gestation( amenorrhea)

Preterm labor is the presence of contractions of sufficient strength and frequency to effect progressive effacement and dilation of the cervix between 20 and 37 weeks' gestation (WHO)

Gynecology and obstetrics clinical protocols & treatment guidelines

Epidemiology

Preterm Birth 12 % of deliveries/yr are preterm71.2% 34-36 weeks13% 32-33 weeks10% 28-31 weeks6% <28 weeks

Preterm BirthSpontaneous preterm labor 30-50%Multiple gestation 10-30%PPROM 5-40%Preeclampsia/eclampsia 12%Antepartum bleeding 6-9%Fetal growth restriction 2-4%Other 8-9%

Survival in Premature Infants23 wks – 17%24 wks – 39%25 wks – 50%26 wks – 80%27 wks – 90%28-31 wks – 90 to 95%32-33 wks – 95%34-36 wks – approaches

term survival ratesSources: march of Dimes, Quint Boenker Preemie Survival Foundation

Review risk factors

Risk Factors for PTDPrevious PTBMultiple gestationIncreased uterine size

(Polyhydramnios, twins)

Uterine abnormalities Maternal InfectionsPlacental pathologyMaternal traumaSmoking (Substance

abuse)

Maternal age extremes

AnemiaLow BMI < 20cervical

incompetencySevere stressorsShort inter-

pregnancy interval

Diagnosis

Signs and SymptomsPelvic and Back painUterine contractionsCervix dilatation and effacement

Investigations FBCVaginal swab for lab analysisUrine analysisMaternal and fetal screening for infectionsObstetric Ultrasound

Review complication

Complications of PrematurityRDSIVHFeeding

difficulties/NECApneaPDAInfectionJaundiceHypothermiaNeurobehavioralROPAnemia

Management

Goals of Treatment of PTLHalt contractions temporary by

tocolysingAllow 48 hr+ for steroids to be givenAllow for transport to delivery

location with NICU capability

SteroidsReduce incidence of RDS, IVH, NEC, sepsis,

and mortality by about 50%Dexamethasone 6 mg IM 12 hr x 4 (cervix

dilatation < 4cm)Dexamethasone 12mg IM 12 hr x 2 ( cervix

dilatation > 4 cm) (Gynecology and obstetrics clinical protocols & treatment guidelines)

TocolysisBeta agonists ( terbutaline, salbutamol)Magnesium sulfateIndomethacinAtosibanNifedipine

TocolysisRisk/benefit ratio of various treatments

Beta agonists (salbutamol, terbutaline)Tachycardia, hypotension, tremor, palpitations, chest

discomfort, hypokalemia, hyperglycemiaMagnesium sulfate

Nausea, flushing, fatigue, diaphoresis, loss of DTRs, respiratory depression, cardiac arrest

IndomethacinMaternal GI SE, premature closure of ductus,

oligohydramniosAtosiban

Possible increase in fetal/neonatal morbidity/mortality; not available in US

CAUTION we should avoid combining tocolytics (Green-top guideline no:1b feb 2011)

TocolysisNifedipine

Low costOralLow incidence of side effects (hypotension, dizziness,

flushing)

Often considered first lineDose:

20mg start dose and 10-20 mg 3 to 4 times daily

Total ≥ 60mg appears to be associated with increase of 3 to 4 fold the bad event of headache and hypotension

Caution: be careful when use in multiple pregnancy, rupture of membrane, sepsis, diabet mellitus and cardiac disease.

(Source: the royal Australian and new Zealand college of obstetrics and gynecology C-obs 15)

Management after TocolysisIf maternal and fetal conditions are stable,

can be managed at homeAvoid excessive physical activity; most

advocate pelvic restContinued tocolytics have not shown definite

benefit

Prevention of PTBReduce/eliminate risk factors, if possibleNot proven to be effective: bedrest, home

uterine monitoring, prophylactic tocolytics, prophylactic antibiotics, abstinence

To retain Preterm labor is the presence of sufficient

uterine contractions to effect progressive cervix changes between 20 and 37 weeks' of gestation

Various strategies that have been used to prevent or treat preterm labor, haven't proven effective.

Tocolysis should be considered only for 2 days- for corticosteroids action,gain time for transfer to a tertiary center .

ReferencesUpToDate19.3 2009 offlinemarch of Dimes, Quint Boenker Preemie

Survival FoundationGynecology and obstetrics clinical protocols

& treatment guidelines Sept.2012the royal Australian and new Zealand college

of obstetrics and gynecology C-obs 15Green-top guideline no:1b Feb.2011

Thanks