Thursday, September 3, 2009

Study: Home Births as Safe as Hospital Births

A new study done in British Columbia comparing 2,889 home births attended by licensed midwives with 4,752 planned hospital births also attended by midwives and 5,331 hospital births attended by a physician found that, for low-risk pregnancies, home birth is just as safe as hospital birth.
Planned home birth attended by a registered midwife was associated with very low and comparable rates of perinatal death and reduced rates of obstetric interventions and other adverse perinatal outcomes compared with planned hospital birth attended by a midwife or physician. (source)

The study only looked at low risk pregnancies, but found that the rate of infant mortality was slightly higher for hospital births (0.35 per 1000 for home births vs. 0.57 for hospital births with midwife vs. 0.64 for hospital births with an MD).

The use of interventions during birth was much lower for the home-birth group:
  • 0.32 times less likely to receive electronic fetal monitoring
  • 0.41 times less likely to have an assisted vaginal delivery
  • 0.41 times less likely to suffer third- or fourth-degree perineal tears
  • 0.62 times less likely to have postpartum hemorrhage
Interestingly, even the women that wanted a home birth but ended up in the hospital still have lower instances of intervention.

Also significant, babies born at home were 0.23 times less likely to require either resuscitation or oxygen after 24 hours and 0.45 times less likely to have aspirate meconium.

Now, the point of this study is not to say, necessarily, that women should give birth at home, but rather to assess the risk of that choice. The researchers wanted to know, "is it safe to give birth at home under a midwife's care," and the answer seems to be "yes." This has as much to do with the screening midwives to on candidates for home birth as with the inherent safety of one environment over the other.

It's very important to recognize the self-selecting bias of this study. Inherently, women choosing to have a home birth are doing so because they are healthy and show no risk factors. But this study shows that this choice does not increase the risk to baby or mother. It's one of the largest such studies done to date, and it's a real landmark.

While it might seem like having all the resources of a hospital would reduce risk, it is also true that certain aspects of hospital birthing also increase the risk in an off-setting way. For example, the higher-stress on the mother, the tendency of doctors to induce labour unnecessarily, and the disturbing trend of medically-unjustified C-Sections (Current Canadian rate of C-Sections is 28% vs. about 31% for U.S. and about 15% for the rest of the industrialized world).

There are a lot of reasons why the rate of C-Sections is so high in the U.S. and Canada, and lots of Doctors and others are worried about it. Many of these seem to be C-Sections-on-Demand--requested by the mother for reasons of convenience, the perceptional that a surgical birth is "easier" than vaginal delivery, etc. It's a major surgery that has the potential to cause a lot of complications. Indeed, it raises the risk for future pregnancies substantially.

The infant mortality rate for the U.S. is terrible: 6.3 per 1000 ranking them 33rd in the world. Canada is a little better: 4.8 per 1000 ranking us 23rd. But this is still far behind countries like Cuba (5.1 per 1000), Slovenia (4.8 per 1000), the Czech Republic (3.8), and world-leader Iceland (2.9 per 1000) source. That's right, a baby is twice as likely to survive in Iceland as the U.S. (FYI, the C-section rate in Iceland is rising, too, from 13.1% in 1987 to 17.9% in 2006. source) I don't know of a study has conclusively linked c-section complications with the higher-than-it-ought-to-be mortality rate in the U.S., but it's all part of the same puzzle.

Here's an excerpt from an article that appeared in the Vancouver Sun recently:
[Dr.] Christilaw says the only thing preventing Canada from seeing "horrific" complication rates from C-sections is the fact women are not having as many babies as they once did.

"A C-section can be a life-saving manoeuvre for a mother or baby. Nobody is saying differently," she says. "What we're trying to say to people is, a C-section is not a benign thing. If you need one, that's different. But you should not be doing this unless you absolutely have to."

C-sections are frequently the end result of a cascade of interventions that often starts with inductions.

Tens of thousands of women in Canada have their labours artificially induced every year, often via intravenous infusion of artificial oxytocin. Oxytocin is naturally produced by the human body. It's what creates contractions in labour. Today in Canada, one in five women who gives birth in hospital is induced.

What doctors fear are stillbirths. But alarmed by the rising rates of inductions, the Society of Obstetricians and Gynecologists of Canada recently urged doctors not to consider an induction until a woman is at least one week past her due date.

Claudia Villeneuve says that women are getting induced "if they're two, three, four days overdue."

"Inductions are rampant," says Villeneuve, president of the International Cesarean Awareness Network of Canada. "You have a perfectly normal mom who comes in with a perfectly normal baby, and now you put these powerful drugs into her system to force labour to start."

The "humane" thing is to offer an epidural, she says. With an epidural, a woman can't feel pain in the lower half of her body. But epidurals slow labour, sometimes so much that labour stops. "Now you have to get this baby out," Villeneuve says. Two-thirds of first-time C-sections are done for "failure to progress."

[Dr. Michael] Klein says epidurals are too often given before active labour is established.

"The majority of women today get their epidurals in the parking lot."

So the cascade continues: epidurals increase the use of electronic fetal monitoring, where electrodes are strapped to the woman's belly to monitor her baby's heart rate.

"It's hard to change positions when you have a fetal monitor on, and an epidural with its little things taped to your back, and an IV in your arm," [Professor of Perinatal Nursing Ellen] Hodnett says. "Why would labour progress normally, if you're stuck in a labour bed with all this machinery on you?"

What's more, EFM is an imperfect technology. It detects subtle changes that can't be picked up by just listening to the baby's heartbeat after contractions, "and those subtle changes are often false positives," Klein says. "In other words, the fetus is OK, you just think it isn't OK." (source)


There are lots of other factors behind the high C-section rate, of course, including the fear of malpractice suits. I'm just trying to make the point that the fewer interventions on mother and baby, the better off both will be. This goes against some of the prevailing wisdom that more medical intervention means lower risk.

A wiser answer to this question--"which is safer"--may simply be, "It depends." If baby and mom are happy and healthy and want a home delivery, there seems to be no medical reason to prevent it and some to recommend it. If, on the other hand, complications seem likely, than you may be better off in a hospital.

-t

1 comment:

...and this blog... said...

Both of ours went very smoothly, FWIW.