PRETERM LABOR AND BIRTH

Posted on Author Binod G C

Preterm labor is defined as one where labor starts before 37 completed weeks, counting from the first day of the last menstrual period. Every year, an estimated 15 million babies are born preterm, and this number is rising and out of this, three-quarters of death could be prevented by a proper intervention. There is wide variation of prevalence that ranges between 10 and 15%. More than 60% of preterm birth occurs in Africa and South Asia. On average, there are about 12% babies born too early in lower-income countries as compared with higher-income countries where it is 9%.

Preterm labor is defined as one where labor starts before 37 completed weeks, counting from the first day of the last menstrual period.

The greatest number of preterm births and the top 5 countries:

  1. India: 3519100
  2. China: 1172300
  3. Nigeria: 773600
  4. Pakistan: 748100
  5. Indonesia: 675700

The highest rates of preterm birth per 100 live births and the top 5 countries:

  1. Malawi: 18.1
  2. Comoros: 16.7
  3. Congo: 16.7
  4. Zimbabwe: 16.6
  5. Equatorial Guinea: 16.5

Sub-categories of preterm birth

  1. Those who are born in less than 28 weeks are termed as extremely preterm.
  2. Those who are born in between 28 to 32 weeks are termed as very preterm.
  3. Those who are born in between 32 to 37 weeks are termed as moderately to late preterm.

High-risk group

  • If there is a history of induced abortion or preterm delivery.
  • Pregnancy following assisted reproductive techniques.
  • Recurrent urinary tract infection.
  • Smoking habits.
  • Low socioeconomic and nutritional status.
  • Maternal stress
  • Pregnancy complications: Pre-eclampsia, antepartum hemorrhage, premature rupture of membranes, polyhydramnios, cervical incompetence, multiple pregnancies, congenital malformation, placental infarction, thrombosis.
  • Iatrogenic
  • Idiopathic (majority)

Diagnosis of Preterm Labor

  • Regular uterine contraction with or without pain.
  • Dilatation more than or equals to 2 cm.
  • 80 % effacement of the cervix.
  • Length of cervix less than or equals to 2.5 cm.
  • Funneling of the internal os.
  • Backache, pressure on pelvic region, and/or vaginal discharge and bleeding.

Management of preterm labor and birth

Prevention of onset of preterm labor

Primary care to reduce the incidence of preterm labor, early detection, and prophylactic treatment, and tertiary care to reduce perinatal mortality and morbidity.

Measures to arrest preterm labor.

  1. Patient should be placed on bed in the left lateral position.
  2. Maintain hydration..
  3. Antenatal corticosteroids to improve newborn outcomes for women at risk of preterm birth from 24 weeks to 34 weeks of gestation.
  4. Tocolytics for inhibiting preterm labor but are not recommended for women at risk of imminent preterm birth for the purpose of improving newborn outcome.
  5. Those women with impending preterm birth before 32 weeks of gestation should be prescribed with magnesium sulfate for prevention of cerebral palsy in the infant and child.
  6. Routine administration of antibiotics is not recommended for women with the intact membrane but are recommended if there is a rupture of the membrane and erythromycin is the antibiotic of choice for prophylaxis.

Appropriate management of labor

The patient is put to bed, adequate fetal oxygenation is maintained, epidural analgesia is given, labor is monitored carefully with continuous electronic fetal monitoring, cesarean section is not recommended unless there is an obstetric indication.

Birth should be gentle and slow, Episiotomy can be done, avoid delaying of the second stage of labor, the cord is clamped immediately to prevent hypervolemia and hyperbilirubinemia.

Effective neonatal care

Thermal care of a preterm newborn with kangaroo mother care as soon as the newborns are clinically stable.

If the newborn is presented with respiratory distress syndrome, continuous positive airway pressure is given, surfactant replacement therapy to intubated and ventilated newborn.

Oxygen therapy with 30% oxygen or air.

Reference

Binod G C

I'm Binod G C (MSc), a PhD candidate in cell and molecular biology who works as a biology educator and enjoys scientific blogging. My proclivity for blogging is intended to make notes and study materials more accessible to students.