Experts name the worst time of day to give birth.

Unless you’re scheduled in for a C-section, one of the most frustrating aspects of pregnancy is knowing when to expect your baby to arrive. It could be early, late, or if you’re really lucky, bang on time.

For years, scientists have tried to discover the optimum day and time to give birth naturally, but new research suggests we may have been looking in the wrong place for answers.

“There are all sorts of studies about the timing of deliveries, but what nobody had looked at before is whether there is some kind of proxy for how fatigued the doctors are,” Dr James Scott, an associate professor of statistics at the University of Texas says in a new paper published in the American Journal of Obstetrics and Gynecology.

Listen: Tiffiny Hall shares the story of her very difficult birth on our pregnancy podcast. Post continues after. 

Studying unscheduled deliveries in the UK, Scott and his team of researchers assessed the variables of 24,506 births between January 2008 and October 2013. In all instances used in the study, doctors worked on 12-hour shift rotations.

Interestingly, the study showed no major differences between morning, night or day of the week deliveries. Neither did they find major differences between the rank and years of experience between doctors.

What they did find, though, was that things markedly changed when the shift hours were analysed.

It’s in the ninth hour of a shift, Scott says, they found that the likelihood of mothers suffering blood loss and the baby suffering low oxygen levels increase. Or, in other words, when small markers could be missed by fatigued doctors.

“We find that there’s a peak eight to 10 hours after the beginning of a shift when, relative to baseline, the risk of maternal blood loss exceeding 1.5 litres increase by 30 per cent, and arterial pH, a marker for infant distress, is at increased risk of falling below 7.1,” Scott said. (Generally, an arterial pH between 7.3 and 7.4 is considered normal).

natural birth versus caesarean
Source: iStock.

And incredibly, researchers found the risk factor dissipates by around hours 11 and 12 - when doctors nearing the end of their shifts are likely to hand over early or complex labours to those at the beginning of their shifts.

So on one hand, the news is good for expecting mums, because the day and time of day they go into labour really shouldn't matter. But on the other, it may be worth speaking to the doctor on duty if you have concerns.