When you’re hours into labour, experiencing intense pain and eager to meet your new little one, any last-minute change of plans can be alarming. But a new study that looks at different interventions used during delivery found that, in some situations, forceps and vacuum-assisted deliveries can cause more physical trauma for the mom and baby than a C-section.
The large study, which was conducted by researchers from the University of British Columbia and Saudi Arabia, and published in the Canadian Medical Association Journal, measured the risks of using forceps and vacuums at the mid-pelvic stage of delivery (when the baby’s head is midway down the birth canal) in comparison to the risks of a Caesarean section. They found that using forceps and vacuums in this circumstance resulted in higher rates of infant and maternal physical trauma when compared to C-sections done in the same situation.
It's a fairly common scenario: Mom is pushing with everything she's got, and baby's head is midway down the birth canal, but labour stalls. At this point, there are two options for getting baby out safely, explains the study’s lead author Giulia Muraca, a doctoral researcher at the University of British Columbia’s School of Population and Public Health. Doctors can perform a Caesarean delivery, or they can opt for what's called an "operative vaginal delivery," also known as assisted vaginal delivery. In Canada, about 10,000 infants are born via mid-pelvic operative vaginal delivery each year. In cases where babies are in distress (say, with an abnormal heart rate), doctors are likely to choose this method because it's quicker than a C-section to get the infant out in an emergency.
The study found that, in cases where there were no signs of distress, infants were five to 10 times more likely to experience severe, potentially debilitating birth trauma when forceps or a vacuum were used at the mid-pelvic stage compared to if they were delivered via Caesarean section. Those traumas included brain bleeds, palsies that created permanent damage, and severe damage to the spleen or the liver.
Among moms who had mid-pelvic forceps deliveries, 19 percent experienced third- or fourth-degree tearing and, for those who had vacuum deliveries, 12 percent had the same result. “These are severe tears,” says Muraca. “They're the kind of tears that can cause long-term pelvic floor disorders like incontinence, pelvic pain, sexual problems and pelvic organ prolapse.” These delivery methods also resulted in higher rates of other types of obstetric trauma, including lacerations in the high vaginal tract and injuries to the pelvic joints or organs. And both mid-pelvic forceps and vacuum deliveries were associated with increased rates of postpartum hemorrhage compared to C-sections.
This isn’t to say that Caesarean sections are risk-free—the postpartum infection rate was higher for women who had C-sections, for example—but it’s helpful for women to understand the comparative risks for all options. “A woman who undergoes Caesarean delivery is very well aware that she is going to have a scar at the end of it,” says Muraca. “Whereas a woman who undergoes a mid-pelvic forceps or vacuum delivery is not informed that she has up to a one in five chance of ending up with a third- or fourth-degree severe perineal tear.”
While previous studies had compared various birth interventions, some of the literature was inconsistent or not as detailed, and many of the large-scale comparisons took place decades ago, when obstetric practices were vastly different.
Though you can’t control when an intervention might be needed during delivery, you can talk to your doctor beforehand about what will be done in case you need that medical assistance. Have a conversation with your care provider before you go into labour, suggests Muraca. “When you have an instrument applied when the baby has not descended far down in your birth canal, there are risks, and we know those risks now. So, factor those into your birth plan, have an open dialogue with your practitioner about what their skill level is and how comfortable they are performing these operations,” she says.
Many health care providers won't even try to perform mid-pelvic operative vaginal delivery, she explains, and having that information is great for patients, because if they are set on a vaginal delivery, they might consider switching to someone who is very skilled at performing this procedure. Muraca says it’s also important to note that, in some cases, when a baby is showing signs of fetal distress, a mid-pelvic operative delivery can be life-saving, as there may not be time for a C-section. Also of note: If the baby is further than midway down the birth canal, forceps or a vacuum-assisted delivery is the clear choice.
“We're not advocating for increased use of Caesarean delivery, and we're certainly not saying that every woman who experiences this arrest in labour should be delivered by Caesarean. But we are saying that all women should be informed of the risks of all modes of delivery so they can choose,” she says. “At the end of the day, just remember that it's really important to keep asking questions.”