Ask an OB: Prolonged Labor

"Ask an OB" is a weekly series with Dr. Maude "Molly" Guerin, MC, FACOG. If you have a question for her, please share it with us here.

What problems are related to prolonged labor? Is it noble to push for 10 hours or is it risky? -- Long labor mom

Before we get to the particulars of this question, understand that I am assuming that your baby is being adequately monitored and is in perfect shape. The key to understanding this issue is to answer another question: why is labor prolonged? In medical school we simplify prolonged labor it’s the baby, the pelvis, or the contractions. Some of these problems are solvable and some aren’t – we can’t make your baby 6 pounds instead of 9, and we can’t make your pelvis bigger! We can encourage your baby to turn if it’s posterior (position change and patience), and we can make your contractions stronger and more frequent (patience, hydration, nipple stimulation, or the dreaded pitocin!).

So the first thing to do is to know when your labor is longer than average (24 hours in latent phase, 0 to 4 cm; 6 hours in active phase, 4 cm to 10 cm; and 2 hours pushing in a first delivery, 1 hour in any subsequent delivery). Next, try to figure out why your labor is longer. 

• Is it the push? How frequent are your contractions? Every 2 – 4 minutes in active and pushing phase is normal. How strong are your contractions? Experienced birth attendants can feel the uterus during a contraction and judge this. 

• Is it the passenger? What position is the baby in? Again, an experienced provider can often tell how the baby’s head is lying in the pelvis – face up, face down, or in between. How big is the baby? We are notoriously terrible at guessing! I’ve seen ultrasound off by 2 pounds and I’ve personally been off by 3 pounds – pretty bad! But about 80% of the time, experienced providers and ultrasound are accurate to within 1 pound. If you’ve already had a baby you are actually just as good (if not better) than ultrasound or your provider, so use your expert judgment.

• Is it the passage? Experienced providers can feel the pelvic bones (pubic bone, sidewalls, tailbone) and make a reasonable assessment of “small medium or large” pelvis.

All these factors need to be carefully pondered in order to do the right thing for a “prolonged” labor. For instance: here are 2 scenarios with first-time Mom stuck at 7 cm for 3 hours:

Mama One : Observations: Estimated weight 7 pounds. Pelvis feels average. Baby may be posterior (harder to deliver). Contractions have spaced out from every 2 to every 6 minutes over the past 5 hours and have gone from strong to moderate to palpation. Assessment: needs better contractions, and this will also hopefully help baby rotate into a better position. Chance for successful vaginal delivery: high 

Mama Two: Observations: Estimated weight 8#. Pelvis feels borderline. Baby feels in a good position. Contractions are every 2 minutes and strong. Mom went from 2 cm to 7 cm in 4 hours. Assessment: baby having trouble fitting through pelvis despite good labor and good position. Chance for successful vaginal delivery: probably less than 10 - 20%.

I would be more patient with Mama One than I would be with Mama Two. If you are Mama Two where your pelvis is just too small, persisting in labor is all risk and no benefit because your baby isn’t going to fit no matter how long you labor! The longer your baby rams against the pelvic floor, the higher your risk for infection, hemorrhage, lacerations and damage to the uterus during your inevitable c section. 

So, to answer your original question (finally!) : if you are having 4 contractions an hour, you can push 10 hours. If you are having 20 contractions an hour it is just plain dumb to push 10 hours. And risky. Notice that WHERE you deliver and WHO does your delivery are not on the list of things we consider when we are trying to decide what’s best for you. If those things are on the list – beware.

You can read more about Dr. Maude "Molly" Guerin, MD, FACOG, right here.