الفهرس 
ِAcknowledgement
Patients with symptomatic preterm laborOnly 14 pages are availabe for public view
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Abstract
Spontaneous preterm labor (SPTL) and preterm birth (PTB), is the single most important cause of perinatal mortality and morbidity in high income countries despite the enormous efforts over the past several decades.
Preterm labor is defined as regular, painful, frequent uterine contractions causing a progressive effacement and dilatation of the cervix occurring before 37 completed weeks of gestation.
In order to deal with preterm labor properly, we should understand well the complex mechanisms surrounding preterm birth.
The etiology of preterm labor is not single; it is likely to be multifactorial,with genetic, infectious, nutritional, behavioral, and other environmental contributors. Infection is implicated as a significant and major cause accounting about 40% of all cases of SPTL and PTB.
Large number of problems may occur in preterm infants as a consequence of being delivered too early. Bacterial infections are the major cause of mortality and morbidity in preterm infants However; two problems are the most significant causes of neonatal mortality and morbidity in the preterm infants which are neonatal respiratory distress syndrome (RDS) and intraventricular hemorrhage (IVH).
Numerous methods have been implicated in order to predict preterm labor including scoring systems, uterine activity monitors, cervical ultrasound and several biochemical markers. However, all those methods are still poorly sensitive.
There are many tocolytic drugs used to deal with preterm labor; however the real efficacy of those drugs is still debatable. Also there are many maternal complications occurred from the use of tocolytic drugs and should not be underestimated.
Tocolytics are drugs used to suppress uterine contractions. The most widely tested tocolytics are betamimetics. Although they have been shown to delay delivery, betamimetics have not been shown to improve
perinatal outcome, and they have a high frequency of unpleasant and even
fatal maternal side effects. This was the main cause in the growing interest to search for other more effective drugs with fewer side effects.
Magnesium sulfate is widely used as the primary tocolytic agent; Common maternal side effects include flushing, nausea, headache, drowsiness, and blurred vision. The mother should be monitored for toxic effects, such as respiratory depression or even cardiac arrest that can occur at supratherapeutic levels. In addition, magnesium sulfate readily crosses the placenta and may lead to respiratory and motor depression of the neonate. Several observational studies have reported an association of antenatal treatment with magnesium sulfate for preterm labor or preeclampsia with a decreased risk of cerebral palsy in low birth weight or preterm infants.
Nifedipine is a calcium channel blocker drug. It acts by reducing the intracellular entrance of calcium through the slow channel (or L type)
producing an inhibition of contractile activity of non pregnant, pregnant
and postpartum myometrium.
Calcium channel blockers have a lower incidence of side effects in comparison with B-agonists with less impact on maternal well being and
are of shorter duration. They also have minimal effects on maternal pulse rate, systolic and diastolic blood pressure.
The direct maternal adverse effects are related to the vasodilation caused by nifedipine and are primarily headache and facial flushes. Generally, these complaints disappear within 24 hours. This encouraged the RCOG in 2002 to recommend nifedipine as the first line of tocolysis rather than ritodrine.
Many drug therapies were used as tocolytics in cases of preterm labor, however none of them proved to be the best. So the present study was performed to compare three of the used drugs for tocolysis to assess their efficacy and side effects on the mother and fetus.
Doppler ultrasound has been used to measure blood flow velocity in the vessels during the cardiac cycle in the fetoplacental and uteroplacental circulation and has been focused on arteries to evaluate down stream distribution of cardiac out put (Gemburch et al., 2003).
Rizzo et al. (2004) reported the specificity and the sensitivity of the cerebral Doppler as a predictor of neonatal outcome were about 75% and 87% respectively.
Recent studies reported that cerebral/umbilical ratio was more accurate than each of its component in prediction of perinatal morbidity, sensitivity 90% compared with 78% for MCA,and 83% for UA indices (Arbeille etal.,1995).
This study was held in the period from Novamber2014 to Septemper 2015 on 303 patients attended and admitted from the casualty unit of the Obstetric department in Sohag Teaching Hospital with preterm labor pains , intact membranes, singleton pregnancy between 24 and completed 34 weeks gestation, all patients had been dated accurately with a gestational age based on the last menstrual period and if available acorresponding second trimester ultrasound report performed before 20 weeks gestation, they were divided into three groups and assigned for the following drugs:
group A: 101 patients received intravenous ritodrine infusion.
group B: 101 patients received intravenous magnesium sulfate.
group C: 101 patients received oral nifedipine.
The patients were selected according.
The patients were selected according to inclusion and exclusion criteria.
Inclusion criteria:
7. Singlton pregnancy
8. Gestational age between 24-37 weeks.
9. Symptoms such as low backache ,cramping , pelvic pressure, excessive vaginal discharge and vaginal spotting.
10. Regular frequent uterine contractions at least of 30 seconds duration at a rate of more than 4/20 minutes.
11. Cervical changes: dilatation less than 3cm,effacement lessthan50%.
12. Intact membranes.
Exclusion criteria :
1. Gestational age more than 37 weeks or less than 24 weeks.
2. Cervical changes: dilatation more than3cm, effacement more than50%.(patient in active labour)
3. Rupture of fetal membranes.
4. Active vaginal bleeding and placental abruption.
5. Chorioamnionitis and intrauterine infection.
6. Fetal conditions: fetal demise or distress, lethal congenital or chromosomal abnormalities
7. Contraindications to Tocolysis for Treatment of Preterm Labor:
General contraindications
Acute fetal distress (except intrauterine resuscitation)
Chorioamnionitis
Eclampsia or severe preeclampsia
Fetal demise (singleton)
Fetal maturity
Maternal hemodynamic instability
Contraindications for specific tocolytic agents
Beta-mimetic agents
Maternal cardiac rhythm disturbance or other cardiac disease
Poorly controlled diabetes, thyrotoxicosis or hypertension
Magnesium sulfate
Hypocalcemia
Myasthenia gravis
Renal failure
Nifedipine (Adalat, Procardia)
Maternal liver disease
All patients were included in the study who flufil the inclusion criteria were informed in details about the plane of management
Patient who agreed to participate in the study were to sign an informed written consent
Patients who refused to be included proper treatment and mangment has been applied to them according to the hospital department policy.
All patients were subjected to:
1- Verbal consent.
2-Complete history taking.
3- General examination: With special attention to blood pressure, pulse and temperature every 20 minutes until a stable dose was achieved and every 4 hours there after.
4- Abdominal examination: To measure the fundal level, palpate the uterine contractions and monitoring of the fetal heart rate.
5- Pelvic examination: To assess the state of membranes and exclude their rupture, to exclude vaginal bleeding and assess the state of the cervix and measure the bishop score.
6- Sonographic assessment:
To estimate the gestational age, amount of liquor and to exclude placenta previa, placental abruption, major fetal congenital anomalies. Fetal biometry.Measurmeant of Doppler waveforms of umbilical and middle cerebral arteries PI,In addition the cerebroplacental Doppler ratio (middle cerebral artery PI / umbilical artery PI) was calculated.
7- Administration of tocolytic agent in the form of intravenous magnesium sulfate, intravenous ritodrine or oral nifedipine.
8-All patients received 24 mg I.M. dexamethasone divided to 4 doses 6mg/12 hours to promote fetal lung maturation .
9-Complete laboratory investigations: including high vaginal swab.
10-Decision about the mode of delivery, if delivery is anticipated,and neonatal care,with assessment of Apgar score and birth weight.