HOME BIRTH: THE RESEARCH

RESEARCH FINDINGS

Several leading health organizations support planned home birth as an option for low-risk women. These organizations include the World Health Organization, the Royal College of Obstetrician and Gynaecologists and the Royal College of Midwives, the American Public Health Association, the American College of Nurse- Midwives, and the National Perinatal Association. The American College of Obstetricians and Gynecologists (ACOG) acknowledges that each woman has the right to make a medically informed decision about delivery but takes the position that hospitals and accredited birth centers are the safest settings for birth.

If you are considering home birth, you’re probably aware that there is a great deal of debate about whether home birth is safe. You likely have people in your family or social circle who are opposed to home birthor who at least question its safety. Because the safety of home birth in the US is controversial, it’s important that you understand what the research on home birth does and doesn’t say.

Studies of home birth in several other countries support the view that home birth can be as safe as hospital birth. There are also many US studies, but only some of them relate to home birth attended by a certified nurse-midwife (CNM) or doctoras contrasted with other types of midwives. In Illinois, only CNMs and doctors are currently licensed to attend home births. So the US studies discussed below focus on CNM care. (Doctors attend so few home births that data about their outcomes is not meaningful.) Some of these studies suggest that CNM-attended home birth is as safe as hospital birth; some suggest that hospital birth is safer. You can read about these studies below to decide whether you will feel safe planning a home birth.

The evidence on intervention rates, by contrast, is clear: women who choose home birth as opposed to hospital birth have lower rates of interventions, including:

  • cesarean birth
  • induction and augmentation of labor
  • instrumental delivery
  • episiotomy
  • epidural

If you plan a home birth, you should be prepared for the possibility of transfer. The research studies show that around 11–17% of US women who begin labor at home end up transferring to the hospital. Only about 4% of these transfers are considered emergencies (so fewer than 1% overall). Your likelihood of needing to transfer is higher if this is your first baby and lower if you’ve already given birth.  

LIMITATIONS OF THE RESEARCH

Before diving into a discussion of the evidence on home birth safety, you should understand the limitations of the research that’s available. In fact, none of the evidence on home birth safety meets the highest scientific standards. Hospital birth has not been proven to be safer than home birth for low-risk women. And, equally, home birth has not been proven to be as safe as hospital birth for low-risk women.

Why? Because it is not practicable to design a study about the safety of home birth that meets the “gold standard” of medical evidence. For a study to meet that standard, women would have to let researchers assign them randomly to have a home birth or a hospital birth. Rightly, few women are willing to let someone else choose for them where to give birth.

The Cochrane Database of Systematic Reviews collects and analyzes all the highest-quality evidence on specific health-related research questions. This organization offers a neutral and reputable summary of the scientific evidence on home birth safety.  

In 2012, Cochrane reviewed the studies on the safety of home birth and concluded:

Increasingly better observational studies suggest that planned hospital birth is not any safer than planned home birth assisted by an experienced midwife with collaborative medical back up, but may lead to more interventions and more complications. However, there is no strong evidence from randomised trials to favour either planned hospital birth or planned home birth for low-risk pregnant women.

http://cochranelibrary-wiley.com/doi/10.1002/14651858.CD000352.pub2/full

So as you read about the best research evidence that’s available, keep in mind that no one can say with certainty that home birth is or isn’t as safe as hospital birth.

SAFETY

1. THE EVIDENCE ON THE SAFETY OF HOME BIRTH IS MIXED

a. Well-designed studies of home birth as practiced in other countries suggest that home birth can be as safe as hospital birth

Several large and well-designed studies of home birth come from developed countries outside the US, including two studies from Canada and a large study from England. This body of evidence supports the view that home birth can be as safe as hospital birth.

The first of the Canadian studies, from 2009, was a prospective cohort study, meaning that women were enrolled in the study before they gave birth and that a comparison group of women who gave birth in the hospital was included. Janssen PA, Saxell L, Page LA, Klein MC, Liston RM, Lee SK. Outcomes of planned home birth with registered midwife versus planned hospital birth with midwife or physician, CMAJ 2009. DOI:10:1503/cmaj.081869. The researchers looked at outcomes for all women in British Columbia who planned home births with registered midwives over a 5-year period. (Registered midwives in Canada have training comparable to that of certified nurse-midwives here in the US.) The researchers compared those outcomes to outcomes for other women who were attended by the same group of midwives as the home birth group, and who would have been eligible for home birth but chose hospital birth instead. In addition, the researchers looked at outcomes for a sample of women who planned hospital births attended by doctors and who were matched for risk factors with the other two groups.

The researchers concluded:

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.

So in this study, outcomes were equally good at home as in the hospital (and interventions were lower).

The second Canadian study, from 2015, was a retrospective cohort study, meaning that women were identified for the study after giving birth and that a comparison group of women who gave birth in the hospital was included. This study accessed the database of the provincial Ministry of Health to compare a group of nearly 11,500 Ontario women who were planning home births at the time their labors began to a matched group of nearly 11,500 women with comparably low-risk pregnancies who planned to birth in a hospital attended by a midwife. Hutton EK, Reitsma AH, Kaufman K. Outcomes associated with planned home and planned hospital births in low-risk women attended by midwives in Ontario, Canada, 2003-2006: a retrospective cohort study. Birth 2009;36:180–9.

Again, researchers found that outcomes were equally good at home as in the hospital:

The rate of perinatal and neonatal mortality was very low (1/1,000) for both groups, and no difference was shown between groups in perinatal and neonatal mortality or serious morbidity. . . . All measures of serious maternal morbidity were lower in the planned home birth group. Jump cite

These studies offer good evidence that home birth as it is practiced in Canada is as safe as hospital birth.

A study from England, referred to as the “Birthplace in England” study, was a prospective cohort study like the British Columbia study, meaning that women were enrolled in the study before they gave birth and that a comparison group of women who gave birth in the hospital was included. Brocklehurst P, Hardy P, Hollowell J, Linsell L, Macfarlane A, McCourt C, et al. Perinatal and maternal outcomes by planned place of birth for healthy women with low-risk pregnancies: the Birthplace in England national prospective cohort study. Birthplace in England Collaborative Group. BMJ 2011;343:d7400.

Over a two-year period, the researchers followed the pregnancies and births of nearly 80,000 women, including over 18,000 women planning home birth, over 29,000 women planning birth in midwife-led birth centers, and over 32,000 women planning birth in the hospital.

In this study, for those women who had given birth before, researchers found no difference in outcomes, whether they planned to give birth at home or in the hospital:

[M]ultiparous women [women who have already had a baby] planning birth at home experience fewer interventions than those planning birth in an obstetric unit with no impact on perinatal outcomes.

However, this study did find a difference for first-time mothers (termed nulliparous women) when looking at the combined risk of a variety of adverse outcomes—including admission to the Neonatal Intensive Care Unit, early neonatal death, neonatal encephalopathy, meconium aspiration syndrome, brachial plexus injury, and fractured humerus or clavicle. The risk of having one or more of these adverse outcomes was higher for babies born at home to first-time mothers:

Adverse perinatal outcomes are uncommon in all settings, while interventions during labour and birth are much less common for births planned in non-obstetric unit settings. For nulliparous women, there is some evidence that planning birth at home is associated with a higher risk of an adverse perinatal outcome.

Like the two Canadian studies, the Birthplace in England study provides good evidence that, for experienced mothers at least, home birth is as safe as birth in the hospital. For first-time mothers, the policy in England is to offer home birth but to counsel mothers on the higher risk.

As you consider this evidence, you need to keep in mind that these studies come from health systems where home birth is well integrated. Home birth midwives in these systems have uniform and recognized credentials. The criteria to decide whether a woman is eligible for home birth are established and applied consistently. Obstetricians and midwives collaborate to care for women who develop complications. Transport from home to hospital is planned for and well coordinated.

The picture is different here in the United States.

b. The special challenges of studying home birth in the US

Each state regulates home birth separately. This means that home birth midwives do not have uniform licensing credentials across the US, and there is no single agreed-upon set of criteria to decide whether a woman is eligible for home birth. In addition, home birth is much less well integrated in the US system of maternity care than in the UK, Ontario, or British Columbia (as examples). This means that home birth midwives and doctors in the hospital may not collaborate well if transport from home to hospital becomes necessary. All of these factors are likely to affect the safety of home birth. Researchers are challenged to analyze data sets that include births attended by providers with different credentials, to women with different risk profiles, who had different options for transport and back-up care.

Another challenge to studying home birth in the US (and elsewhere) is that a well-designed study will compare groups of women who intended to birth at home (even if they ended up transporting to the hospital in labor) with groups of women who intended to birth in the hospital. In many of the US studies, that data was unavailable, so the researchers instead compare women who actually gave birth at home (whether they planned to or not) to women who actually gave birth in the hospital (even if they had planned a home birth).

Finally, many of the US studies rely on data from birth certificates. The birth certificate form was revised in 2003 to distinguish between planned and unplanned home births, which has improved the usefulness of birth certificate data for home birth studies. However, there are still many limitations and inaccuracies in birth certificate data. See for instance, Martin JA, Wilson EC, Osterman MJ, Saadi EW, Sutton SR, Hamilton BE. Assessing the quality of medical and health data from the 2003 birth certificate revision: results from two states. Natl Vital Stat Rep. 2013 Jul 22;62(2):1-19.

For these reasons, every study of home birth in the US has methodological flaws. (Here are links to two academic articles explaining this further: Nove A, Berrington A, Matthews Z. The methodological challenges of attempting to compare the safety of home and hospital birth in terms of the risk of perinatal death. Midwifery.2012;28(5):619‐626. doi: 10.1016/j.midw.2012.07.009; DOI:10.1111/jjns.121116; Elder HR, Alio AP, Fisher SG. Investigating the debate of home birth safety: A critical review of cohort studies focusing on selected infant outcomes. Japan Journal of Nursing Science. Volume 13: 3 July 2016 297-308.)

And because every US study has flaws, opponents of home birth tend to discount the studies that show equally good outcomes at home, while home birth advocates tend to discount the studies that show worse outcomes at home.

So where does that leave you, as a pregnant woman in the Chicago area trying to decide whether to choose a home birth?

Since home birth is regulated differently in different states, it is important to look at the safety of home birth under the rules where you live. For Chicago-area women, what’s relevant is the evidence on safety for home birth attended by certified nurse-midwives (CNMs) and doctors. That’s because, in Illinois, CNMs and doctors are the only types of providers licensed to attend home births.

TYPES OF HOME BIRTH PROVIDERS IN THE US

While certified nurse-midwives (CNMs) can practice throughout the United States, certified professional midwives (CPMs) are regulated on a state-by-state basis. In 30 states, CPMs are licensed professionals. The state of Illinois, however, does not currently recognize the CPM credential. Several groups are working to pass legislation (the Home Birth Safety Act) that would better integrate certified professional midwives into the maternity care system of Illinois. That legislation would recognize the CPM credential and allow certified professional midwives to be licensed to attend home births in Illinois. You can learn about that effort here.

c. The evidence about the safety of CNM-attended home birth in the US

Here are summaries of several studies of CNM-attended home birth in the US. (Again, doctors attend so few home births that the evidence on their outcomes is not meaningful.)  Some suggest that CNM-attended home birth is as safe as birth in the hospital; some suggest that hospital birth is safer.

  1. Studies suggesting that CNM-attended home births are as safe as birth in the hospital

A 2013 retrospective cohort study by Cheng et al. used birth certificate data to examine neonatal health measures for over two million low-risk births in 27 states, of which over 12,000 were planned home births. Cheng YW, Snowden JM, King TL, Caughey AB. Selected perinatal outcomes associated with planned home births in the United States. Am J Obstet Gynecol 2013;209:325.e1–8.

The researchers found higher rates of two negative outcome measures (low Apgar scores and neonatal seizures) in the home birth group when all types of attendants were included. But when the researchers looked separately at home births attended by certified nurse-midwives, there was no statistical difference in outcomes, except that rates of neonatal intensive care (NICU) admissions were lower for the home birth group:

Compared with births that occurred in hospitals, infant outcomes after planned home births that were attended by certified nurse-midwives did not differ significantly, except that infants who were born in a hospital were more likely to experience NICU admissions.

So this study offers some evidence that planned home birth attended by a CNM is as safe as hospital birth.

There’s an earlier study by Wax et al. that is often cited as proving that home birth is unsafe. Wax JR, Lucas FL, Lamont M, Pinette MG, Cartin A, Blackstone J. Maternal and newborn outcomes in planned home birth vs planned hospital births: a meta-analysis. Am J Obstet Gynecol 2010;203:243.e1–8. In this 2010 study, researchers pooled and analyzed data from seven earlier studies of home birth safety. (This pooling of data is called a meta-analysis.) Only two of these seven studies were from the US, and the numbers of US women included in the pooled data were small overall. The Wax study is therefore not primarily a study of home birth in the US, and it should be considered in the context of the other international studies discussed above.

In any case, like the 2013 study by Cheng et al., the Wax study reported a higher neonatal mortality rate for out-of-hospital birth when all types of attendants were included. But when the researchers analyzed the data for studies that included only births attended by certified midwives and certified nurse-midwives, they found that the difference in neonatal death rates [babies dying in the month after birth] for out-of-hospital birth was not statistically significant:

The analysis excluding studies that included home births attended by other than certified or certified nurse midwives had findings similar to the original study, except that the [odds ratios] for neonatal deaths among all (OR, 1.57; 95% CI, 0.62–3.98) and nonanomalous (OR, 3.00; 95% CI, 0.61–14.88) newborns were not statistically significant.

In other words, when the researchers looked only at data for women attended by CNMs (or CMs, their international equivalent), there was no statistically significant difference in safety outcomes between the home and hospital birth groups. So this study does NOT support the claim that home birth attended by certified nurse-midwives is unsafe.

2) Studies suggesting that CNM-attended hospital birth is safer than CNM-attended home birth

There are two large US studies that analyzed linked birth and death certificate data and found better outcomes for CNM-attended births in the hospital than for CNM-attended births at home.

In a study published in 2010 by Malloy et al., researchers examined data from linked birth and death certificates for over 1.3 million low-risk births attended by midwives in a five-year period (2000–2004). Malloy MH. Infant outcomes of certified nurse midwife attended home births: United States 2000 to 2004. J Perinatol. 2010 Sep;30(9):622-7. doi: 10.1038/jp.2010.12. Epub 2010 Feb 25.

Of those 1.3 million births, over 1.2 million were CNM-attended hospital births and 13,500 were CNM-attended home births. The researchers found a lower risk of neonatal mortality for CNM-attended births in the hospital compared to CNM-attended births at home (5 per 10,000 compared to 10 per 10,000).

A similar study published in 2016 by Grünebaum et al. examined data from linked birth and death certificates for over 1.16 million low-risk deliveries attended by midwives in a four-year period (2006–2009). Grünebaum A, McCullough LB, Arabin B, Brent RL, Levene MI, Chervenak FA (2016) Neonatal Mortality of Planned Home Birth in the United States in Relation to Professional Certification of Birth Attendants. PLoS ONE 11(5): e0155721. https://doi.org/10.1371/journal.pone.0155721Of those 1.15 million births, about 1.1 million were CNM-attended hospital births and 18,000 were CNM-attended home births. Like Malloy et al., the researchers found a lower risk of neonatal mortality for CNM-attended births in the hospital compared to CNM-attended births at home (3.2 per 10,000 compared to 10 per 10,000).

These studies suggest that neonatal mortality rates are higher for CNM-attended home birth compared to CNM-attended hospital birth.

 3) Studies that are not relevant because they don’t include outcomes for CNMs or don’t separately analyze outcomes by type of provider

There are several other studies that you may have heard about, including:

However, these studies included births that occurred at home attended by non-certified midwives as well as (in some cases) non-midwife attendants such as family members. Since the outcomes are not broken out by type of birth attendant, these studies don’t tell us much about the safety of home birth to low-risk women attended by doctors and CNMs.

d. The absolute risk that your baby will die or be seriously injured is very small, whether you choose home or hospital birth

Of course you want to know whether home birth and hospital birth are comparably safe. Unfortunately, while there is certainly good evidence to support the safety of home birth, there is also evidence that suggests that home birth is less safe than hospital birth.

But it’s also important to keep in mind that the absolute risk to your baby is very low, whether you choose hospital or home birth. Based on the study by Grünebaum et al., if you choose hospital birth with a CNM, the likelihood that you will lose your baby shortly after birth is 3.2 in 10,000, and if you choose home birth with a CNM, the likelihood that you will lose your baby shortly after birth is 10 in 10,000. You can say, “The likelihood that my baby will die is three times as high if I have a home birth.” Or you can say, “The likelihood that my baby will die at home and wouldn’t have died in the hospital is 6.8 in 10,000, which is less than 0.1%.” Both statements are supported by evidence, but they may feel very different to you.

e. You have control over some of the factors that affect home birth safety

Until home birth is integrated into the Illinois maternity care system the way it is in Ontario, British Columbia, and the UK, you can’t count on home birth being as safe as hospital birth. But you can create for yourself at least some of the conditions that make home birth safe in those countries:

  • You can find out whether you have any of the risk factors that are likely to make home birth less safe. (See Am I High Risk?)
  • You can choose an attendant who has credentials comparable to those of the international midwives who have such good outcomes. In Illinois, the only providers licensed to attend home births (CNMs and doctors) have those credentials.
  • You can check that your provider has a relationship with a back-up obstetrician, or you can line up someone for yourself.
  • You can ensure that transport is readily available and you can be open to the need to transfer. (Research the hospitals in your area that are in easy reach. In the Chicago area, you are likely to have several choices. Find one that you’ll be comfortable going to if you need to transport in labor.)

 

THINKING ABOUT SAFETY

To measure the safety of birth in one setting versus another, researchers typically look at outcomes like neonatal mortality, Apgar scores [a measure of the baby’s health right after birth], and admission to the Neonatal Intensive Care Unit (NICU). Unlike these outcomes, intervention rates (for instance, cesarean birth, induction and augmentation, and epidural and episiotomy rates) are not generally considered measures of safety.

But when you want to answer the question “Is this setting safe for me?,” intervention rates may be as important as outcomes. For instance, after a cesarean birth—and especially after repeat C-sections—your risk of complications in future pregnancies goes up. So while a cesarean birth is certainly an “intervention,” you might also consider it a safety outcome. Avoiding a C-section in this pregnancy makes your future pregnancies safer.

So as you think about safety, keep in mind that the research on “outcomes” in different settings is just a starting place.

intervention rates

2. INTERVENTION RATES ARE OVERALL LOWER FOR WOMEN WHO PLAN HOME BIRTH

Every study of home birth to date, worldwide, reports lower rates of medical intervention (including cesarean birth, induction, Pitocin augmentation, episiotomy, epidural analgesia, forceps or vacuum extractor use, antibiotic use, etc.) for low-risk women who plan to deliver at home as compared to low-risk women who plan to deliver in the hospital. This is true even when you include outcomes for women who planned a home birth but ended up transferring to the hospital.

In the US, one exception is the 2015 study by Snowden et al. (a study which included births attended by midwives who were not CNMs). This study found a higher rate of maternal blood transfusion in the planned home birth group as compared to the planned hospital birth group. But all other types of interventions were lower. Snowden JM, Tilden EL, Snyder J, Quigley B, Caughey AB, Cheng YW. Planned out-of-hospital birth and birth outcomes. N Engl J Med 2015;373:2642–53.

Taken as a whole, the research pretty clearly shows that women who birth at home have lower rates of interventions.

It is certainly reasonable to weigh this difference when you consider whether to have your baby at home or in the hospital.

TRANSFER RATES

3. TRANSFER RATES

None of the studies examining CNM-attended home births in the US included transfer rates. The largest prospective study of US home birth (mostly non-CNM-attended births) found that about 11% of women planning home births transferred to the hospital during labor. Cheyney M, Bovbjerg M, Everson C, Gordon W, Hannibal D, Vedam S. Outcomes of care for 16,924 planned home births in the United States: the Midwives Alliance of North America Statistics Project, 2004 to 2009. J Midwifery Womens Health 2014;59:17–27.

A subsequent study reported a 16.5% transfer rate. Snowden JM, Tilden EL, Snyder J, Quigley B, Caughey AB, Cheng YW. Planned out-of-hospital birth and birth outcomes. N Engl J Med 2015;373:2642–53. Only about 4% of these transfers are considered emergencies (so less than 1% overall).  Your likelihood of needing to transfer is higher if this is your first baby and lower if you’ve given birth before.

SO WHAT DOES THIS ALL MEAN FOR YOU?

As you ponder whether home birth is right for you, keep these things in mind:

  • No one can say conclusively that hospital birth is safer than home birth overall, or that home birth is as safe as hospital birth. We simply don’t have definitive evidence either way.
  • The evidence on the safety of CNM-attended home birth is mixed. Some studies suggest that CNM-attended home birth is as safe as hospital birth. Some studies find an increased rate of neonatal mortality for home births attended by CNMs compared to hospital births attended by CNMs.
  • Home birth is safest IF
    • you are low-risk
    • you choose a licensed provider (in Illinois, that means a CNM or a doctor), and
    • you have ready access to back-up care if complications arise.
  • The absolute risk of your baby dying is very small, whether you choose a hospital or home birth.
  • Your risk of interventions is lower if you plan a home birth.

So thoughtfully consider the risks. Read through the “Learn More” page on home birth to weigh considerations other than safety and intervention rates. Talk to a licensed home birth practitioner to make sure you’re eligible to birth at home. Talk to others who have had home births. Consider your alternatives.

In the end, you have the right to consider anything and everything that is important to you to make the choice that is best for you and your family.