Researchers are calling for a reassessment to the safety practises of using forceps or vacuum deliveries in Canada, citing a new study that suggests rates of trauma among mothers and babies who need the interventions are higher than previously reported, and higher than some other countries.
The study, published Monday in the Canadian Medical Association Journal, says one-in-four deliveries that require forceps and 13.2 per cent of those that use a vacuum resulted in physical trauma to the mother, while nearly one per cent of babies delivered with either intervention experienced trauma.
Maternal trauma included severe perineal tears, impaired sexual health, urinary or fecal incontinence, and other pelvic disorders while severe neonatal trauma could include long-term nerve damage and brain injury.
Giulia Muraca, a perinatal epidemiologist and assistant professor at McMaster University who led the study, called the trauma rates "unacceptably high," adding that pregnant people need to be made more aware of the potential risks of forceps and vacuum deliveries.
"If we don't talk about this, we're compromising women's autonomy and their ability to make evidence-informed decisions about interventions in their childbirth," she said.
Forceps are tong-shaped instruments that are inserted into the vagina and placed around the baby's head to help guide it down the birth canal. Vacuum extraction does the same, but with a small cup that attaches to the baby's head to provide gentle suction.
The techniques, which fall under the term operative vaginal delivery (OVD), may be used during the second stage of labour if labour is stalled, if there is a risk to the fetus, or to avoid pushing in people with certain health conditions, including heart problems.
The other option is typically a surgical caesarean section.
Muraca said OVD is used on a case-by-case basis, depending on the individual pregnant person's situation. But the comfort level of the clinician delivering the baby also plays a role.
"You'll see more younger obstetricians and care providers probably doing caesarean deliveries, mainly because they don't feel as comfortable using these instruments," she said.
There are certain instances in which OVD cannot be used, including on premature babies.
Forceps and vacuum deliveries have accounted for about 10 to 15 per cent of all deliveries in Canada, Australia and the United Kingdom in recent years, a figure Muraca said has been dropping over the past two decades.
The United States, which relies more on C-sections, uses OVD in about five per cent of its deliveries.
Muraca said use of OVD is based on guidelines that recommend they be performed by trained health-care professionals. But with the interventions being used less frequently now, there are fewer opportunities for clinicians to get that training.
The study says that while OVD may be associated with low rates of morbidity "in carefully selected circumstances," high rates of trauma suggest those "ideal conditions" don't apply to present-day obstetric practice in Canada.
"The problem is that the risk associated with these deliveries is really heavily dependent on the care-provider's expertise," Muraca said. "So because of that, the consensus surrounding operative vaginal delivery safety really warranted inquiry again.
"We are telling women that these are safe when they're performed by trained personnel. But we don't really know what that looks like in contemporary practice."
The study analyzed more than 1.3 million term deliveries in Canada, excluding Quebec, from April 2013 to March 2019. Of those, 38,500 used or attempted the use of forceps while 110,987 used or attempted vacuum extraction.
Muraca says rates of trauma may be higher in Canada than some other countries because of differences in reporting. But it could also be impacted by Canada's lower rate of episiotomy — cutting through the area between the vagina and anus — during forceps or vacuum deliveries.
She says previous studies have shown that some trauma can be prevented when episiotomies are used in conjunction with forceps deliveries.
Muraca said Canadian researchers and clinicians should start "meaningfully interrogating" why rates of trauma are so high among forceps and vacuum deliveries and reassess safety guidelines around them.
"We really (need) to have some high-level thought about why these injuries are absurdly high," she said. "And we have to be transparent to pregnant individuals about the rates of these traumas."
This report by The Canadian Press was first published Jan. 10, 2022.
Melissa Couto Zuber, The Canadian Press