Unecessary Labor Inductions Lead to Breathing Problems

In the largest study of its kind, researchers find that the risk of severe breathing problems increased significantly in babies born prematurely, even those born between 34 and 37 weeks gestation.

Health experts define ‘preterm’ as less than 34 weeks’ gestation, ‘late preterm’ as 34-37 weeks’ gestation and ‘full term’ after 37 weeks gestation.
Many previous studies have shown that compared with full-term babies, those who are born too early are at higher risk of dying shortly after delivery and are more likely to suffer neonatal complications that require lengthy stays in the hospital.

A new study, published in the July 28 issue of JAMA, was conducted by University of Illinois at Chicago researcher Dr. Judith Hibbard and colleagues from the Consortium on Safe Labor found that babies born between 34 weeks and 37 weeks gestation are much more likely to have respiratory illness compared to infants born at full term; and their risk of respiratory illness decreases with each additional week of gestation until 38 weeks.

"Even at 37 weeks, babies were three times more likely to have respiratory distress syndrome compared to babies born at 39 or 40 weeks," said Hibbard, UIC professor of obstetrics and gynecology and lead author of the study.

The study found that late preterm births accounted for 9 percent of all deliveries. Thirty-seven percent of late preterm infants were admitted to the neonatal intensive care unit, compared with 7 percent of term infants. Respiratory illness occurred in 9% of late preterm births.

Hibbard said concern has grown in recent years about the problems associated with late preterm birth and the increasing number of babies delivered early. Respiratory illnesses such as respiratory distress syndrome (RDS), transient tachypnea (wet lungs), pneumonia and respiratory failure can lead to other problems such as longer hospitalization, the need for a ventilator or antibiotics, and issues with feeding and failure to gain weight.

Researchers studied all newborns, 34 weeks gestation or greater, with respiratory problems admitted to neonatal intensive care units. Late preterm births were compared with full-term births for resuscitation, respiratory support and respiratory diagnosis.

Using a statistical model, researchers examined infant respiratory illnesses at each gestational week, controlling for factors that influence respiratory outcomes such as maternal medical conditions, length of labor and mode of delivery, and birth weight.

Babies born at 34 weeks were 40 times more likely to have respiratory distress syndrome, a breathing difficulty that often requires a ventilator, than babies born at 38 weeks or later.

At 37 weeks’ gestation, the point at which mothers may ask for an elective Cesarean section or induced delivery, infants are three times more likely to have respiratory problems that require medical intervention than 40 weeks’ gestation infants.  . "That's a remarkably increased risk," notes Hibbard, "and I have to admit, much higher than I was expecting."

Despite the accepted 37-week full-term cutoff, the American College of Obstetricians and Gynecologists officially recommends that babies not be delivered (unless medically necessary) until after 39 weeks. Yet some 9% of all deliveries in the U.S. still occur just shy of 37 weeks, and a recent study found that as many as 23% of late pre-term births — between 34 weeks and 37 weeks — occur for no documented medical reason.

The Mayo Clinic suggests the following medical reasons for inducing labor:

    * At least 10 days beyond due date, and labor hasn't started naturally.
    *Water has broken, but no contractions.
    *Infection in your uterus.
    *Baby has stopped growing at the expected pace.
    *Not enough amniotic fluid surrounding the baby.
    *Placenta has begun to deteriorate.
    *Mother’s medical condition that may put her or baby at risk, such as high blood pressure or diabetes.

Sometimes women request elective induction for personal comfort, lifestyle or work reasons. Keep in mind that unnecessary intervention poses unnecessary risks such as:

    *Premature birth complications including difficulty breathing, yellowing of the skin and the whites of the eyes (jaundice), and other     problems. Even inductions close to term may cause these problems.
    *Low heart rate. The medication used to induce labor (oxytocin) may provoke too many contractions, which can diminish your baby's     oxygen supply and lower your baby's heart rate.
    *Infection for both mother and baby.
    *Umbilical cord may slip into the vagina before delivery, which may compress the cord and decrease the baby's oxygen supply.
    *Poor labor progress and the need for a C-section.

By definition, induction promotes delivery before your body is ready for labor.  “The OB community needs to assess indications for induction of labor," said Hibbard, who hopes that this study will help clinicians to counsel their patients about the importance of not requesting medically unnecessary inductions.

Laura Lamp King