Expecting mothers are substantially more likely to suffer from delivery complications in hospitals during nights, weekends and holidays, a study has found.
Researchers from Colorado State University in the US analysed more than two million cases from 2005 to 2010, using detailed data obtained from the Texas Department of State Health Services.
The study, published in Risk Analysis: An International Journal, looked at labour or delivery complications including third- or fourth-degree perineal laceration, ruptured uterus, unplanned hysterectomy, admission to intensive care unit and unplanned operating room procedure following delivery.
The research team focused only on women with a single birth (ie not twins) who had gestation of more than 20 weeks, a delivery attended by a physician, and a normal labour onset.
The study evaluated whether delivery complications vary by work shift, increase as the hours pass within work shifts, and increase on weekends and holidays.
The results suggest that the odds of a mother experiencing a delivery complication are 21.3 per cent higher during the night shift, and that the odds of a delivery complication increase 1.8 per cent with every hour worked within a shift.
They also found that a mother delivering an infant on a weekend is 8.6 per cent more likely to encounter a complication than a mother delivering on a weekday.
Births occurring on holidays are particularly susceptible to labour or delivery complications, with holiday births being 29.0 per cent more likely to have a complication, the study showed.
The research also explored whether delivery complication rates are higher in teaching hospitals, and whether they increase when a new cohort of residents enter teaching hospitals in July, causing abrupt declines in physician experience and coordination between members of the healthcare team.
Mothers delivering their infants in teaching hospitals are 2.2 times more likely to experience a delivery complication than mothers birthing at non-teaching hospitals.
The risk also increases by a multiplicative factor of 1.3 at teaching hospitals in July, when new residents join the staff rotation.
By June, after a full year of training and integration, the risk of a delivery complication at these same hospitals is statistically indistinguishable from chance.
"Across an ensemble of hospital situations where clinical quality is known to vary independently of patient characteristics and volume, we see corresponding variation in the risk of preventable harm to expectant mothers," said Sammy Zahran, from Colorado State University in the US.
Obstetric care in hospital settings is a team effort and ineffective teamwork has been implicated in an estimated 75 per cent of preventable medical errors.
The researchers hypothesise that hospitals could decrease the risk of harm to mothers by putting more emphasis on scheduling inexperienced physicians with more senior health professionals, among other things.
