Preterm Labor
Lin Qi de
Definition
Preterm Labor, Labor occurring
prior to the completion of 37 weeks’
of gestation(≥28 weeks’),or 196-258
days from the last menstrual period
(LMP),
Etiology
Maternal factors,
(1) Clinical complication:cardiovascular,
liver,renal dieases,PIH,severe anemia
et al
(2) Uterine distortion,Leiomyoma,uterus
didelphys,uterus septus,Incompetent
cervix and other abnomalities
Fetal and placental factors,
(1) Hydramnios
(2) Multiple pregnancy
(3) PROM
(4) Placental abruption
(5) Placenta praevia
(6) Urinary,intra- amniotics infection
Symptoms and Signs
Uterine contraction,
(irregulation regulation)
Increase or change in vaginal discharge
(mucous,watery,light bloody discharge)
,Taking up, of the cervix
Progressive dilatation of the os
Preventation
(1) Antenatal care
(2) Treat clinical complication
(3) Operation for the os
Management of PTL
The purpose of treating PTL, delay
delivery,if possible,until fetal maturity
fetal alive
no fetal distress
no PROM
(1) Rest in the bed,lie on left side
(2) Prevent RDS,dexamethasone 5mg im
3days to enhance pulmonary maturity
(3) Tocolysis therapy,
?-adrenergic agents,increase cAMP in
cell which decreases free calciun(?2-
receptors predominate in the
uterus,lung and blood vessels)
Prostaglandin synthetase inhibitors,
decrease prostaglandin(PG) production
Calciun channel blockers,
prevent calcium entry into muscle cells
Magnesium sulfate:competes with
calcium for entry in to cells
25%MySO4 + 5%GS 500ml 80-100ml/h(first hour)
pay attention to,
?The respiratory,more than 16 /min
?The knee reflection must be exist
?The urine volume must be more than
600ml/24h (25ml/h)
?Calcium resistance must be prepared