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In this edition of Potpourri, let’s talk about a few things that have a similar theme: common practices that have been adopted without scientific evidence which have now been proven worthless.

Delayed pushing

Delayed pushing or “laboring down” is when a woman is encouraged to wait to push for some time after she is completely dilated. This practice is thought to lead to lower Cesarean rates and less time pushing, among other claimed benefits.

There has never been high-quality data to support this practice which has become very common across the country, and it’s based on some fundamental misconceptions. The first is that women should push “when they feel the urge” to push. This mantra is often repeated as the reason why women should avoid pushing just because the cervix is completely dilated. But the origins of the axiom predate epidurals. In the old days, to avoid unnecessary cervical exams (which, among other things, increased the risk of infection), doctors and nurses were told to just leave the woman alone until she felt the urge to push, which usually would occur when she was 9-10 cm and starting to have fetal descent. There wasn’t much value in cervical exams because there weren’t interventions for women who had slow or stalled labors (like oxytocin), so you just had to wait and see; and if a labor was arrested for 30+ hours with ruptured membranes, the last thing you wanted to do in the pre-antibiotic era was do something that increased the risk of chorioamnionitis, like stick your fingers in the vagina to see if she was completely dilated (of note, we usually did rectal exams for this same reason).

Alas, the axiom of “don’t push until you feel the urge to push” has gone by the wayside, along with rectal exams during labor. Epidurals very often take away the very urge to push that people are expecting.

The second stage of labor starts when the cervix is completely dilated and ends when the baby is born; thus, delayed pushing is always associated with a longer second stage of labor. I know this point seems obvious (and it is), but several people over the years have argued with me about this. Of course, what they mean is that pushing time is reduced with delayed pushing, but that is not the same thing as the length of the second stage. We need clinical trials to tell us whether it is valuable to lengthen the second stage of labor by one hour to save 6 minutes or so of pushing.

There have been several trials over the years which have shown a lack of value of delayed pushing. Of these, one of the best has recently been published. Cahill et al. randomized 2414 nulliparous women with epidurals to immediate pushing versus delayed pushing for one hour. They found no differences in the rate of Cesarean delivery, neonatal morbidity, or perineal lacerations. The delayed pushing group pushed for 9 minutes less, but, of course, had labors that were 32 minutes longer since they waited to push. This extra length of the second stage of labor meant that the women who had delayed pushing had higher rates of infection and postpartum hemorrhage.

So, delayed pushing didn’t help and made women more at risk for bleeding and infection.

Stop routinely utilizing delayed pushing. If you need to wait a few minutes for a family member to get to the hospital, that’s okay, but don’t recommend to women that they delay pushing or claim that the practice is beneficial (more data here and here).

Pushing position

One thing that has somehow become a part of the natural birth community without evidence is the belief that upright pushing/birthing positions are superior to supine or lying down positions.

The reasons given are largely aesthetic and not scientific: women always gave birth in upright positions before we invented epidurals or gravity helps the baby come out or something like that. I think the real root is mostly reactionary: since women in hospitals largely lie down while birthing, let’s change it up.

The idea that gravity helps the baby come out in a significant way is ludicrous but is deeply rooted in flawed, misogynistic biases. If one believes that bed rest is a useful strategy to prevent labor (it isn’t), then getting upright must help deliver a baby. The forces generated by the uterus during a contraction, augmented with maternal pushing efforts, are many orders of magnitude greater than the forces exerted on the fetus by gravity alone. Those gravitational forces are counteracted by just a few Newtons of force, which are easily provided by the maternal pelvic floor in its resting state. Babies don’t fall out due to gravity. Think of it this way: let’s say I need to pick up a fifty-pound dumbbell and someone adds the weight one feather to the mass; removing that one feather isn’t going to make the task appreciably easier. That feather, by scale, is the effect of gravity on parturition. Think of this the next time you hear a suggestion about gravity helping deliver the baby.

Still, outcomes are what matter. For that, we can look at this trial of 3093 nulliparous women with epidurals who were randomized to an upright versus lying down pushing position in the UK. The women in the upright position had a 5.9 percentage point lower rate of spontaneous vaginal delivery than the group of women lying back. The evidence is clear: lying down (at least with an epidural) results in far more spontaneous vaginal deliveries.

To be fair, most studies that have looked at birthing positions have provided mixed results and almost all suffer from significant methodological issues or applicability issues. Many have been conducted in settings where there is a very high rate of operative vaginal deliveries, cesarean deliveries, and episiotomy use. Switching to upright positions likely takes away the midwife’s or doctor’s opportunity to cut episiotomies, and so studies have found fewer episiotomies. However, they have also shown more third- and fourth-degree laceration rates (likely because the upright position also takes away the opportunity to support the perineum and the speed of delivery). Studies that have found fewer operative deliveries with upright positions in a setting of 20-40% operative delivery rates just don’t apply to my practice at all. Again, having patients in an upright position likely resulted in the doctors’ hands and eyes being out of the vagina and therefore less opportunity for forceps and vacuums and episiotomies and impatience. So, one must be careful with the study design: Are we getting bad doctors uninvolved or is there truly a difference in outcomes based upon anatomy and physiology?

The bottom line is this: women should be allowed to birth in any position they feel most comfortable and lying back is probably best if they have an epidural. As with delayed pushing, don’t claim benefits that aren’t there (like less severe perineal trauma or lower cesarean rates) and don’t create reasons for those supposed benefits (like gravity).

Cystoscopy after hysterectomy

Here is more evidence that performing a cystoscopy after hysterectomy for benign indications is not worthwhile. In this retrospective study of over 39000 women undergoing hysterectomy for benign indications, there was no difference in the rate of diagnosis of delayed urinary tract injury up to 30 days.

My practice (as I state in my book, which you should buy) is to perform cystoscopy only in cases where there are large masses or concomitant pelvic floor surgeries that significantly increase the risk of urinary tract injury.

Stop making excuses for your high Cesarean rate

It’s amazing that this study had to be done, but, here it is: a group of 56 hospitals in California implemented a Cesarean delivery reduction program that affected 119,000 women. They were able to reduce their primary Cesarean rate by over 4 percentage points without any increase in neonatal morbidities. In fact, the rate of severe newborn complications actually declined with fewer Cesareans. Hmm.

As a side note, their rate of Cesarean delivery was still too high, but it’s solid evidence that lower rates of Cesareans are good for mothers AND babies. It’s not a trade-off. Of course, eventually, it will become a trade-off. Many Cesareans are absolutely necessary. But we can likely get into the single digits for the rate of primary Cesarean for term, singleton, vertex pregnancies before we see that trade-off become an issue.

Stop making excuses for your high rate of Cesarean delivery.

Don’t do expensive and complicated procedures that don’t provide benefit

This sounds obvious, but the whole story of robotic hysterectomy for benign hysterectomy screams that doctors don’t get it. Many times, doctors will push the prolapsed uterus back into the vagina so that they can do a robotic hysterectomy instead of a vaginal one. One excuse for this has been that they want to do a robotic sacrocolpopexy to repair the prolapse. Apart from the fact that the robotic approach is no better than the laparoscopic approach, the more important issue is that it is no better than the vaginal approach. This new study of 186 women undergoing either vaginal high uterosacral colpopexy versus robotic sacrocolpopexy showed no difference in outcomes.

While outcomes are the same, some other things should be pointed out: the vaginal high uterosacral colpopexy is much, much cheaper, takes less time, and can be done in any hospital that a vaginal hysterectomy can be performed.

Stop getting your “science” from industry.