Monday, May 29, 2006

Urgent transfers

Not all the studies broke down the transfer rate by urgency. I could find three that gave enough information to determine which transfers were done on an emergency basis. As might be expected, the neonatal deaths came from this group. If you look at the death rate for emergency transfers from homebirths, the results are even more dismal.

Johnson & Davis: 11 deaths in 252 emergency transfers for a death rate of 44/1000.
Murphy & Fullerton: 4 deaths in 36 emergency transfers for a death rate of 111/1000.
Janssen: 8 deaths in 142 emergency transfers for a death rate of 56/1000.

These death rates are enormous and confirm obstetricians most serious criticism of homebirth, that babies in need of emergency care will die for lack of such care at home.


10 Old Comments:

Can you really extrapolate data in this way? I mean, the actual number of deaths in the Johnson study was 14/5418. Not 21/1000. I see where you're getting your number from, but it still doesn't make for accurate statistics. That would be like saying - how many emergency c-sections for fetal-distress resulted in a baby dying, and then drawing conclusions about the safety of hospital birth...

By Anonymous Diane West, LM CPM, at 12:42 AM  

I did that, too.

The neonatal death rate for emergency C-sections appears to be somewhere in the range of 9/1000. That's very much lower than the neonatal death rate for emergency homebirth transfers.

By Blogger Amy Tuteur, MD, at 6:47 AM  

Amy, something's wrong with those numbers. A total of three babies died in the Janssen homebirth group, including one antepartum death. Where are you getting eight deaths?

By Blogger Jamie, at 11:02 AM  


" A total of three babies died in the Janssen homebirth group"

No, 8 babies died, but Janssen removed 5 because they died of congenital anomalies. I have no way to remove congenital anomalies from the hospital group so they needed to be added back in to make an accurate comparison with a hospital neonatal death rate of 9/1000 after emergency C-section.

By Blogger Amy Tuteur, MD, at 12:35 PM  

Okay, I'm with you part of the way. They only mention those deaths as a footnote to one of the tables, which left me puzzled.

But you're making some big assumptions here. You assume first that every transfer during labor is an emergency (here's the quote: "The overall rate of transport to hospital for the home birth group was 21.7%, with 142 (16.5%) transports occurring during labour." I read that as distinguishing pre-labor transfers, for post-dates or medical problems, not non-emergency transfers. It would be quite unusual to have such a high rate of emergency transfers.)

Second and third assumptions: you're saying that every baby with a lethal anomaly was both an emergency transfer and an intrapartum/neonatal death, when some of them could have died before labor and some families could have opted at time of diagnosis for a peaceful home death. And you're still including the antepartum death in this study (as well as one of the antepartum deaths in Murphy-Fullerton), which I cannot get my mind around. How is it that planning a homebirth causes antepartum death? And which hospitals are reporting favorable IUFD outcomes?

By Blogger Jamie, at 1:02 PM  


Math first:

Amy is doing you a favor by using 142. In fact, Amy is using the "safe but certain" method of estimates. She's choosing the number which benefits her argument least. I have always wished the home birth folks would emulate this.

You are right that 142 is a very high rate of transfer. But if--as you suggest, and as we all suspect--some of the 142 transfers were NOT emergent, then the death rate for the transfers goes UP, not down. If only half the transfers were emergent, the death rate for emergent transfers would double.

I dn't see any realistic way to get the data regarding the (hypothetical) "babies who die in their mothers' arms" that you keep bringing up. This seems like a very strange hypothesis.

But hey: let's trade assumptions. aka "guesses". I'll pretend that fully 1/8 of those babies weren't transferred because their parents wanted them to die. You'll agree to a more reasonable transfer rate of 100 which were actually emergent.

Now we're at 70/1000, which is WORSE than before. Even if you want to pretend that 1/4 of the babies died "intentionally" at home, you're at 60/1000.

As for antepartum:

A home birth doesn't "cause" antipartum death per se. Technically that would probably be an issue with prenatal care, which we're not discussing.

But it would be proper to include them for both hospital and home birth statisics in a few instances.

First, there's the issue of determining whether a death is antepartum or not. I imagine that in some cases it's very simple to determine whether the death was truly antepartum, while in other cases it is much more difficult.

You DON'T want to "hide" an effect by removing antepartum deaths which were really NOT antepartum deaths. Because you may not have 100% assurance of the time of death, it's probably better to include them. This also eliminates much possibility for bias on the part of the practitioners.

Second, the hospital data may not be available without those deaths. So you may need to "balance" by including them for both sides.

By Blogger sailorman, at 2:02 PM  

There's another way of looking at this, too. Take the J&D numbers, for instance: women planning a homebirth should know that this study suggests they have a 3.4% chance of requiring emergency transfer to the hospital, or a 96.6% chance of not requiring same. If your numbers are correct, of those requiring emergency transfer, 4.4% wound up with a dead baby; 95.6% did not. .034 x .044 = .001496, or a rate of 1.5 intrapartum/neonatal deaths per thousand births. (The remaining .5/1000 comes from the births not involving emergency transfers.)

I don't think many families planning homebirths would be surprised by those percentages, though I could be mistaken.

Which are the three deaths you're excluding here? The anomaly deaths? I can't follow your thinking by reading the paper. Whichever ones they are, there's a case to be made that the midwives did an excellent job of identifying the situations in which they needed more help than they could offer. Most of the time the help was prompt enough; in a few situations it wasn't.

A rate of 2.0/1000 intrapartum/neonatal deaths (which includes higher-risk breech and twin births), is within the range of numbers I've seen so far for low-risk hospital birth. (Have you cited studies on perinatal death rates for low-risk women other than those in J&D?)

While we can nitpick in hindsight about which of the C-sections in England and Wales were actually emergencies (from the study you cited of emergency C-section outcomes), the fact is almost 12% of births ended with what were recorded as emergency C-sections. That's on top of all the forceps/vacuum deliveries for fetal distress, and all the non-assisted deliveries where mothers were exhorted to push with all they had because the babies needed to be born as fast as possible. It supports what homebirth advocates have been saying all along: more emergencies arise in hospitals, even for low-risk women.

Planning a homebirth means accepting a small risk that your baby will need emergency care not available in your home, and a much smaller risk that such care won't be available promptly enough. But in general, homebirth means a lot less drama than hospital birth.

Sailorman, I saw your response to me when I previewed this comment. I'll get back to you later today, but let me just say I'm good with the smaller divisor = larger quotient rule. Did you see my reply to you down below about public health and homebirth? Interested in your response when you get to it.

By Blogger Jamie, at 2:35 PM  

Jamie, I've always said that the risks at homebirth are small, but they are real. My central point has been that this is important information that MUST be available to women contemplating a homebirth. I have not seen a single homebirth advocacy website or publication that makes it clear that the risk of neonatal death at homebirth is higher than the risk of neonatal death at hospitals.

In fact, most homebirth advocacy websites and publications assert that homebirth is safer for the baby than hospital birth. That is simply not true and it is long past the time when advocates should have acknowledged it.

Homebirth means accepting a small, but real, increased risk to the baby, in exchange for a much greater chance of avoiding unnecessary procedures for the mother.

By Blogger Amy Tuteur, MD, at 3:28 PM  

Amy, Janssen says nothing about congenital anomaly outcomes. I just looked again at the table and realized I had assumed all the babies with anomalies died, but that would be a ton of deaths given the total number of anomalies (23 in the three groups). I think you should revise your calculation.

By Blogger Jamie, at 1:55 PM  

"Janssen says nothing about congenital anomaly outcomes."

That's true. However, I'd be willing to be a lot of money that all the babies died in the homebirth group and they were removed to improve the statistics. I would also be willing to be that many of the babies with congenital anomalies who were born in the hospital (with either doctors or midwives in attendance) lived. That way, when congenital anomalies were removed from all the groups, the homebirth statistics got better and the hospital statistics stayed the same or got a tiny bit worse.

I am a very cynical person.

By Blogger Amy Tuteur, MD, at 7:07 PM