Preterm Labor &

PROM

Preterm Labor

• When onset of labor prior to completion of 37 weeks (259 days) of pregnancy, after the attainment of period of viability is called preterm labor.

• The lower limit varies in different countries WHO- 22wks and 500gm United kingdom- 24wks India- 28wks

Incidence

• It varies 5-15% in different part of world & India

Aetiology

• In >30% cases exact cause of preterm labor is not known

• Certain risk factors which increases the incidence of preterm labor.

Risk factors

• Genital tract infection- Group B streptococci - Bacterial Vaginosis - Chlamydia, Gonorrhea

• Ante partum Hemorrhage• Overdistended Uterus- polyhydromnios - Multiple pregnancy

• Uterine anomalies - unicornuate,Bicornuate -septate,arcuate, Fibroid uterus

• Incompetent Cervical os

• Acute fever & maternal illness

• Premature rupture of membrane

• Low socioeconomic status, poor nutrition, & anaemia

• Smoking & tobacco addiction

• U T I

• Pervious H/o preterm labor (17-40%)

• Iatrogenic- Induction of labor without knowing

EDD

Diagnosis of PTL

• P/A- Regular uterine contractions > 4 in 20 minutes or >8 in 60 minutes, with changes in cervix

• Cervical effacement >80% Cervical dilatation > 1 cm

Preterm Labor

Can be 1. Advanced PTL 2. Early PTL 3. Threatened PTL

Advance PTL

Diagnosis: -Regular uterine contraction >4 in 20 mts or >8 in 60 mts -Cervix >3 cm dilated - 80% effaced

Management of Advanced PTL • Allow delivery if

-Cx is >4cm dilated

-Signs of chorioamnionitis

-Baby malformed

-Severe placental insufficiency

• But if Cx is <4cm and none of the above is present

give tocolysis,corticosteroid & antibiotic if indicated

• Aim – to give corticosteroid to prevent RDS &IVH in baby & mother with fetus in utero can transfer to place where neonatal care facility available

Early PTL

Diagnosis: -Regular uterine contraction -Cervix > 1 cm & <3 cm dilated -Cervix > 80% effaced

Management of Early PTL

• If there is signs of – Chorioamnionitis

- Congenital anomaly in fetus

- Mother& fetus condition is

not good

Allow labour and delivery.

• But if - Fetal condition is not compromised

- Maternal condition is good

- No signs of chorioamnionitis

- Membranes are intact

Then Expectant management includes-

- Bed rest in left lateral position

- Antibiotic if infection is evident

- Tocolysis

- Corticosteroid if pregnancy < 34 weeks

Threatened PTL• When there are regular uterine contractions,

Cervix is <1cm dilated , length of cervix

<2.5cm on USG & GA <37 wks- Threatened PTL

• Diagnosis is by – Clinical examination

- USG

- Detection of fetal fibronectin in

cervical discharge

• FFN in cervical discharge is usually absent between 24-34wks , so if it is present it is predictor of PTL

• If FFN is negative in cervical discharge indicates no delivery with in 7 days.

• If threatened PTL is diagnosed by clinically,

USG & FFN then give tocolysis and corticosteroid to woman.

Doses of Corticosteroids

• Betamethasone- 2 doses,12mg IMI,24 hours

apart.

OR

• Dexamethasone- 6mg IMI 12 hrly total 4 doses

• Corticosteroids are beneficial when delivery occurs at least 48 hrs after 1st dose

Tocolytic Drugs

Various tocolytic drugs which can be used are :-

* Nefedipine

* Betamimetics –Isoxsuprine

-Terbutaline

- Retrodine

* Indomethacin

* Mgso4

* Nitroglycerine

Doses of Tocolytic drugs

Nefedipine • It is the best first line tocolytic• It is a calcium channel blocker causes smooth

muscles relaxent• Doses – Initial 20-30mg orally followed by 10mg

4-6hrly till uterine contraction cease f/b

10mg 8hrly for about 1wk. • Side effects- headach,hypotension,nausea

flushing

Bitamimetic Tocolytics

Turbutaline• It can be given IV or subcutaneous• For IV- Dissolve 5mg of terbutaline in 500ml

of RL, each ml contains 10ug

-Start with 5ug (o.5ml)/min. & increase

the dose of 5ug every 10-20min.till

uterine contraction stops.

-Maximum dose 30ug/min.• Subcutaneous dose-o.25mg every 3-4 hours for

12hrs• A maintenance dose-2.5-5mg orally 4-6 times/day

Ritodrine

• Beta mimetic drug causes smooth muscle relaxation by B2 receptor stimulation

• Doses- given by IV infusion

- Start with 100ug/min. & increase the

dose by 50ug every 10-20 min. till

the uterine contraction stops or

maximum dose of 350ug

- Continue infusion for 12hrs after the

contractions stop.

Isoxsuprine• Doses- 0.2-0.5mg/min I V infusion for 12hrs

followed by 10mg IMI every 6-8 hour for

24hours

Side effects of Beta mimetics• Headache• Palpitation , Tachycardia• Hypotension , Hypokalemia• Pulmonary oedema & Cardiac failure

Indomethacin

• It is an excellent tocolytic but is not used as first line because it causes constriction of ductus arteriosis.

• Dose – Initial dose 25-50mg orally followed by 25mg every 4-6 hours for 3days.

• Side effects – Heart burn, G.I.bleeding

Thrombocytopenia, asthma

Mgso4

• Dose – 4-6 gm (20% solution) i.v. slow in 20-30

min. followed by an infusion of 1-2gm/hr

& continue for 12 hrs after the contraction

have stopped• Side effects- Headache , flushing

- Muscular weakness

- Rarely pulmonary oedema

Nitro-glycerine

• It is usually given in form of patch• Dose – 0.1- 0.4 mg/ hr• Side effects – Tachycardia

- Headache

- Hypotension

(PROM)Premature Rupture Of Membranes

orPrelabour Rupture Of Membranes

• Spontaneous rupture of fetal membrane any time after the period of viability but before the onset of labor is called PROM. When it occurs before 37 wks completed gestation it is called PPROM.

• Incidence – 10%

Causes of PROM

• Polyhydromnios• Multiple pregnancy• Incompetent Cervix• Poorly applied presenting part in unstable lie and

malpresentations• Traumatic- ECV, amniocentesis• Weakness of chorion & amnion- developmental

or inflammatory,chorioamnionitis

Diagnosis

• H/O- discharge of fluid p/v• P/S- examination shows liquor coming out through

cervical os it may be clear or meconium stained.• Sometimes liquor is not appreciable through os

D/D – liquor amnii

- urine

- vaginal discharge

Confirmatory Tests for liquor Amnii

• Fern Test- Take the sample of vaginal fluid on a slide & allow it to dry then look under microscope. Crystallization of liquor looks like fern.

• Nitrazine Test- Normal vaginal PH is 4.5-5.5 but PH of liquor is 7-7.5. Put the Nitrazine paper on vaginal discharge Liquor turns the Nitrazine paper deep blue.

• Nile blue sulphate Test- when centrifuged cells of watery discharge is stained with Nile blue sulphate it shows, orange blue coloration of cells indicates presence of exfoliating fetal cells in liquor

• Indigo-carmine Test- When other tests are negative and still doubt of leaking. Inject

2-3cc of indigo carmine in amniotic cavity & put a tampon in vagina wt. for ½-1hr if tampon turns blue indicate liquor.

• Detection of fetal fibronectin in endocervix & vagina between 24-34 wks of GA indicates PROM

• USG - Shows less liquor

Hazards of PROM

• Maternal- Increased liability to infection

- chorioamnionitis

- Premature placental separation

- Postpartum endometritis

• Fetal - Cord prolapse

- Premature labor & hyaline

membrane disease

- Intrauterine Infection

Management ofPROM

• Initial Assessment- main objective of the initial assessment are:-

- Confirm the diagnosis of PROM

- To determine the gestation of the fetus

- To identify the women who need to

deliver

Management of PROM

• If Pregnancy is ->37 weeks

- Congenital anomalies

- Fetal distress , cord prolapse or

- Signs of chorioamnionitis

Then deliver the patient.• Induction of labor- if no contraindication

Management of PPROM

• Balance between risk of infection in expectant management & Premature labor

• Shift the patient where the facility for neonatal care is available .

• If pregnancy is >34 and <37 weeks

- Haemogram, cervical swab c/s

- Antibiotics

- Careful watch on signs of chorioamnionitis

Maternal & fetal conditions

- If no spontaneous labor in 24-48hrs-induction

of labor

• If pregnancy <34 weeks Expectant Management- The aim is to prolong the

pregnancy for fetal maturity

- Bed rest

- send haemogram & Cervical swab c/s

- give corticosteroid & tocolysis if contraction +nt

- Antibiotics

- Watch for signs of chorioamnionitis,

Maternal & fetal condition.

Signs of chorioamnionitis

• Temperature > 100.4*F and 2 or more of:

-Maternal tachycardia pulse >100/min.

-Uterine Tenderness

- Foul smelling vaginal discharge

- Leukocytosis15000cmm

- C-reactive protein >2.5mg%

- Fetal tachycardia >160 min

if there is no other site of infection