Obgyno Wino Podcast Episode 49 - Operative Vaginal Birth
Updated: Nov 27, 2020
"I theorize that there is a spectrum of consciousness available to human beings. At one end is material consciousness. At the other end is what we call 'field' consciousness, where a person is at one with the universe, perceiving the universe. Just by looking at our planet on the way back, I saw or felt a field consciousness state." - Dr. Edgar Mitcher, astronaut
PB#219 - Published April 2020
1. Episiotomies should never be performed routinely, even if you were trained to do it routinely to assist in operative vaginal delivery. If you think it's absolutely necessary, counsel the patient so that she can make an informed decision.
2. Overall, operative vaginal delivery carries low absolute risk for baby and mom w/ comparable relative risk compared to c-section
3. Vacuum-assisted delivery carries higher risks to the fetus when compared to forceps and lower risks to mom.
4. Major benefit to operative vaginal birth is decreased risk of hypoxic injury to the newborn in the event of successful expedited vaginal delivery through operative means (assuming there is concern for fetal acidemia)
5. Forceps, even in trained hands, carries significantly higher risk of severe perineal injury compared to vacuum.
- operative vaginal delivery includes forceps or vacuum extraction
- forceps (big metal things) or vacuum are applied to the fetal skull/scalp in order to assist with a pulling effort in order to expedite delivery
- this PB doesn't go into detail on types of forceps or specifics on how to use them
- forceps delivery is rarely taught in-depth in residency training programs, but vacuums are readily available
- the lower the fetus in the pelvis and less rotation required (in the case of forceps) to facilitate the birth, the lower the risk of injury to baby or mom
- operative vaginal delivery is one important tool for reducing cesarean delivery rates
- this is important because cesarean deliveries carry the risk of hemorrhage, infection, nearby organ damage, thrombosis, pain, and delayed healing time
- long-term risks include abnormal placentation in subsequent pregnancies, all-cause maternal morbidity and mortality in future abdominal surgeries and cesarean deliveries, and risks of trial of labor after cesarean (TOLAC) in subsequent pregnancies
- cesarean deliveries are also costlier to the medical system and, while data reporting on fetal morbidity suggest that it's safer for the kiddo, most guidelines (and study design) fails to consider the impacts of cesarean deliveries on newborn microbiome, early maternal-child bonding, and maternal mental health (linked studies are exemplar and by no means being presented as "proof")
- all of these risk must be weighed against the relatively low risks of operative vaginal delivery (or expectant management)
- this procedure is contraindicated if the fetal head is not well-engaged in the pelvis or if fetus has a known or strongly suspected bone demineralization condition (e.g. osteogenesis imperfecta) or bleeding disorder (e.g. hemophilia, von Willebrand disease, or thrombocytopenia)
- Vacuum is specifically "discouraged" at GA <34 weeks)
Vacuum vs Forceps
- vacuum is easier to learn, but forceps has the advantage of being able to provide rotation
- forceps are more effective (in trained hands) and carry higher success rate but also carry higher risk for 3rd and 4th degree perineal lacs
- no difference after 5 years post-birth in risk of urinary incontinence or anal sphincter dysfunction
- vacuum technique: cup placed 2 cm anterior to the posterior fontanelle, centered over sagittal suture, ensuring no maternal tissue is included
- forceps technique: sagittal suture must be aligned with the shanks, posterior fontanelle must be one finger breadth above the shanks, and lambdoid sutures must be equidistant from the forceps blades
Episiotomy or no episiotomy?
- if you are still performing routine episiotomies for any patient for any reason, you need to retire; patients should run
- if you are still performing episiotomies unless you think it is ABSOLUTELY ESSENTIAL, you need to retire; patients should run
- episiotomies are barbaric -> expect delayed healing, prolonged discomfort with mediolateral episotomies; there is high risk of extension to 3rd and 4th degree lacs with midline episiotomies
- if you MUST, please consent the patient first. You can always spare 30 seconds.
Counseling on risks
Risk to mom:
anal sphincter injury - in one study, increased risk even when controlling for other independent risk factors including prolonged second stage of labor, fetal size, maternal age and obesity, shoulder dystocia, and episiotomy (in other studies it has been harder to isolate operative delivery independent of these other risk factors)
Risk to baby:
vacuum: scalp laceration, cephalohematoma, subgaleal bleeds, retinal hemorrhage, hyperbilirubinemia, and intracranial hemorrhage
Note: In one study, 28% of cephalohematomas diagnosed in setting of vacuum-assisted vaginal delivery occurred when suction cup was attached for >5 minutes. Having said this, releasing suction pressure between contractions didn't reduce that risk
forceps: risk of facial lacerations, facial nerve palsy, corneal abrasions, external ocular trauma, skull fracture, and intracranial bleeding
intracranial hemorrhage: 1 in 650-860 operative vaginal deliveries
neurologic complications: 1 in 220-385 operative vaginal deliveries
overall no difference in neonatal mortality or severe morbidity for operative vaginal delivery compared to cesarean delivery
best to have neonatal resuscitation team available for birth if available given risk (albeit low) of these acute complications
no long-term morbidity associated w operative delivery (or when they grow up to be kids)
Pearl: Major benefit to operative vaginal birth is decreased risk of hypoxic injury to the newborn in the event of successful expedited vaginal delivery through operative means
- Caput succedaneum: edematous scalp swelling above the periosteum that crosses the suture lines
- Cephalohematoma: subperiosteal bleeding that does not cross suture lines
- Subgaleal hemorrhage: blood accumulation between the periosteum of the skull and the epicranial aponeurosis
Is it ok to attempt operative vaginal delivery when fetal macrosomia is suspected?
- of course, anything is possible
- first off: we stink at predicting newborn weight by 3rd trimester ultrasound
- macrosomia is an independent risk factor for birth injury (independent of operative delivery)
- best to consider whole clinical picture, including other risk factors of shoulder dystocia, etc. such as adequacy of maternal pelvis and progress of 2nd stage of labor
You are attempting operative vaginal delivery. When do you give up?
- no consensus on this. I generally keep it on for no longer than 4-5 contractions, pulling with each
- switching from one instrument to the next carries higher risk than each instrument in isolation (albeit still absolute low risk)
- are you seeing progress? No? Then might be time to recommend cesarean
Should I provide routine antibiotics prophylactically if assisting through operative vaginal delivery?
- no, though you might consider it your patient ends up with a 3rd or 4th degree lac
A note on rotating the fetus with forceps...
- Forceps can assist with rotation, assuming you've learned this technique
- You can also rotate manually
- Rotation can be helpful in facilitating delivery, as birth through occiput posterior position is far more challenging (and damaging to the perineum) than through the occiput anterior position
- Great review article from the green journal discussed rotation from occiput posterior