1. Preterm labor

2. Definition
Preterm labor (PTL): regular uterine contractions accompanied by progressive cervical dilation and / or effacement at greater than 20 weeks and less than 37 weeks 0 days’ gestation.1
Preterm birth: delivery before 37 weeks 0 days gestation.1

3. Signs of preterm labor Menstrual-like cramping
●Mild, irregular contractions
●Low back ache
●Pressure sensation in the vagina or pelvis
●Vaginal discharge of mucus, which may be clear, pink, or slightly bloody (ie, mucus plug, bloody show)
●Spotting, light bleeding

4. What are the maternal risk factors for preterm labor?
No partner
Low socioeconomic level
Anxiety, stress
Depression, use of selective serotonin inhibitors
Life events (divorce, separation, death)
Abdominal surgery during pregnancy
Occupational issues (upright posture, use of industrial machines, physical exertion, mental or environmental stress related to work or working conditions)
Multiple gestation

5. Risk factors Polyhydramnios
Uterine anomaly, including diethylstilbestrol-induced changes in uterus and fibroids
Preterm premature rupture of membranes
History of second-trimester abortion
History of cervical surgery
Premature cervical dilatation or effacement (short cervical length)
Sexually transmitted infections
Systemic infection, pyelonephritis, appendicitis, pneumonia

6. Risk factors…… Maternal age (<18 or >40)
Poor nutrition and low body mass index
Inadequate prenatal care
Anemia (hemoglobin <10 g/dL)
Excessive uterine contractility
Low level of educational achievement

7. More risk factors…..
Maternal first-degree family history of spontaneous preterm birth, especially if the pregnant woman herself was born preterm
Fetal anomaly
Fetal growth restriction
Environmental factors (eg, heat, air pollution)
Fetal demise
Positive fetal fibronectin test result in vaginal secretions

8. Risk factors continued……
Bacteriuria
Periodontal disease
Placenta previa
Placental abruption
Vaginal bleeding, especially in more than one trimester
Previous preterm delivery
Substance abuse
Smoking

9. On Haida Gwaii…. Is the birth imminent?
Are we set up for preterm birth if awaiting medivac and poor weather?
Medivac with all positive fFN

10. Scenario #1
Molly is a G4P2 with a history of a preterm birth at 33 weeks following PPROM in Masset 2 years ago. She was medivaced from Masset to Prince George and had a 60 min labor once contractions (started 1 hour after arriving in PG).
Medical history significant for frequent bladder infections. She is a smoker however has been trying to cut down. Her BMI is 33 at current GA. She has gained 20lbs in pregnancy.
She is currently 33 weeks and her pregnancy to date has been uneventful. She is O positive, Rh positive and has a penicillin allergy. Detailed scan was normal, posterior placenta clear of cervix, no previa, normal growth and fluid. She was seen by the visiting OB in 1st trimester and discussed a cerclage and/or prometrium, she declined both. She has a history of BV treated at 20 weeks. Her birth plan was to travel to QC with her midwife for her birth.

11. Scenario #1 continued
The RM is out of town, but antenatals are at the hospital. Molly calls the ER in Masset at 0130 to report that she has mild cramps and her water may have broken. She is advised to come into the hospital for assessment.

12. Preterm labor assessment
Establish dates: LMP and dating ultrasound, SFH = dates?
History (menstrual history, ultrasound, clinical growth)
Review the Antenatal 1 and 2
Vital signs (temperature, BP, respirations, pulse) and assessment of fetal well- being

13. Assessment of PTL Risk factors?
PPROM- Nitrazine, sterile speculum, pooling, ferning is gold standard
Contraction pattern-EFM and put your hands on the belly
- frequency, length, painful, increasing
Show or Bleeding?
IV fluids- dehydration
UTI? – MSU signs and symptoms?

14. Scenario #1A
Upon arrival at the ER in Masset, Molly is still feeling crampy. The RN places an IV and the EFM to monitor contractions and FHR.
The on call GP does a sterile spec to assess for ? PPROM.
There is no pooling, nitrazine/amnioswab negative and ferning unable to do as no fluid.
No show
A fFn swab and GBS swab are done
The fFn swab is found to be negative.
Digital exam: Long post cervix, Multip’s os.
MSU positive for nitrates and Hgb- Rx for antibiotics. ( note: allergy to Penicillin )

15. Fetal Fibronectin
“Fetal fibronectin (fFN) is an extracellular matrix protein present at the decidual- chorionic interface. Disruption of this interface due to subclinical infection or inflammation, abruption or uterine contractions releases fFN into cervicovaginal secretions, which is the basis for its use as a marker for predicting spontaneous preterm birth “
Strong negative predictive value within 2 weeks.
Diagnosis of Preterm Labor UptoDate- preterm-birth

16. When to do fFN After ruling out previa
No bleeding, no semen (in 24 hrs)
No PPROM
Before digital exam
Before GBS swab or other vaginal swabs

17. Scenario A continued Molly is kept overnight for observation
Cramping stops with IV fluids and antibiotics for query UTI
Education around hydration, Braxton Hicks.
Follow up with RM

18. Scenario #1B On call GP does a sterile speculum
Pooling noted and ferning and nitrazine positive- PPROM confirmed.
IV antibiotics ( allergy to penicillin) - Bethmethasone
OB consult and medivac initiated
EFM show contractions 2/10, lasting secs. Palpate mild.
FHR: Baseline 140, moderate variability, no decels and accels to 155 bpm.
Fetal Movement normal

19. PPROM Premature, pre-labor, rupture of membranes ( PROM <37 weeks)
Preterm premature rupture of membranes (PPROM) occurs in 3 percent of pregnancies and is responsible for, or associated with, approximately one- third of preterm births.
The single most common identifiable factor associated with preterm delivery.
Risk factors: Previous PPROM, genital tract infections, smoking, antepartum bleeding

20. Bethamethasone
“A course of corticosteroids should be administered to pregnancies between 23 and 34 weeks of gestation. Data supporting this recommendation were provided by systematic reviews of randomized trials that showed neonatal death, respiratory distress syndrome (RDS), intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), and duration of neonatal respiratory support were significantly reduced by antenatal glucocorticoid treatment” - UptoDate

21. Outcome Scenario #1B a and b
A) Molly is medivaced to Prince Rupert , as she may not make it to Prince George with the contraction pattern and dilatation- the medivac arrives in record time as it is a clear sunny day…. All is well.
B) Molly delivers a 33 week baby, vigorous in the Masset hospital 3 hours after admission. Preterm NRP guidelines are followed by the staff. ITT team arrives and mom and baby are safely medivaced to Prince George…. All is well.
Debrief and document.

22. Questions? Comments?