Does birth setting impact birth outcome?

By Dr. Liji Thomas, MDMay 14 2023

In the USA, the vast majority of mothers deliver in hospitals, with less than 2% giving birth in birth centers or at home. However, few systematic attempts have been made to understand how the latter trend impacts maternal health. A new research paper published in the American Journal of Obstetrics and Gynecology uses available data to conclude that hospital births provide better perinatal outcomes in all cases, with increased benefits in high-risk pregnancies.

​​​​​​​Expert Review: The impact of birth settings on pregnancy outcomes in the United States. ​​​​​​​Image Credit: christinarosepix / Shutterstock

Introduction

Among high-income countries, maternal and neonatal morbidity and mortality rates are relatively high in the US. Interestingly, Black and Native Americans have higher rates than the rest of the population.

Most hospital deliveries are carried out by doctors, with less than a tenth being performed by Certified Nurse-Midwives (CNMs). Conversely, in birth centers or at home, over half the deliveries are accomplished by CNMs and about 37% by non-certified midwives. The rest are primarily by midwives not certified by the American Midwifery Certification Board (AMCB), with 3% and 0.6% being by physicians in birth centers and at home, respectively.

The established practice of giving birth in hospitals continued through the coronavirus disease 2019 (COVID-19) pandemic, with a decrease of only 0.3% in hospital births during 2019-20. Most of those who opted out of the hospital birth system chose to deliver at home, with the figure rising from 1% to 1.2%.

Direct data comparing births in and out of hospital is lacking. Moreover, some home births become complicated and end up in hospital, with the resulting adverse outcomes becoming part of the hospital’s outcomes instead of being attributed to the original outside-hospital delivery pathway.

Home births and those occurring in birth centers do have their obvious and significant advantages, of course. Interventions and procedures that are unnecessary for the specific patient’s case are largely avoided. However, the authors say it is demonstrably wrong to think that having fewer interventions always improves the safety of childbirth.

The trend towards hospital deliveries was originally stimulated by the observation that a ‘normal’ delivery may deteriorate to become a high-risk one quite rapidly and unpredictably. The speed at which life-endangering complications arise, requiring multidisciplinary care, makes it more challenging to reduce the chances of adverse outcomes from out-of-hospital childbirth. This is because the need for transportation and emergency equipment, operative treatment, and to call in the services of multiple professionals takes up precious time, detracting from the patient’s quality of care when the delivery process begins out of hospital.

Some severe and sudden complications that put the lives of both mother and baby at risk and require immediate specialized intervention include post-partum hemorrhage (in almost six of a hundred deliveries), amniotic fluid embolism (the same proportion as above), shoulder dystocia (in three of every hundred), abruptio placentae (in up to one in a hundred deliveries), uterine scar rupture ( in over one in a hundred post-Caesarean section deliveries),

What did the study show?

The study identified the shortfalls in data regarding deliveries in hospital and outside. The Centers for Disease Control and Prevention (CDC) maintains statistics on the 3.5 million births in the USA each year. However, they are registered to the institution where they occurred and not where they were intended to occur.

This could lead to underestimation of the risks of out-of-hospital births that end up being transferred to hospitals, often after complications have set in that lead to less favorable outcomes. Secondly, birth certificates are not created for stillborn fetuses, causing a gap in the data.

The Midwives Alliance of North America (MANA) Statistics Project and the American Association of Birth Centers also maintain birth registries on a voluntary basis. However, these collect only half the births outside hospitals, and cannot be generalized due to their collection from a heavily selected population segment.

Several earlier studies have shown that births planned for out-of-hospital settings are associated with higher perinatal morbidity and deaths compared to hospital settings. This applies across the board, whether in neonatal deaths following deliveries in women aged 35 years or above, those following term deliveries, overall deliveries, or post-term pregnancies.

The researchers compared births assisted by a hospital midwife to those assisted by CNMs at home, other midwives at home, and unintended home births. In all cases, when compared with those births performed by a hospital midwife, the mortality among the newborns was more than two to eight-fold higher in home births.

For instance, for a term baby, a hospital midwife-assisted birth was associated with ~3 deaths per 10,000 live births. With intended home births, this rose to three-fold higher rates when assisted by a CNM or direct-entry midwife. With other midwives, the mortality rate increased almost seven-fold, to 21 deaths per 10,000 live births.

Again, in those with a previous C-section, who often opt for home births, the risks for adverse neonatal outcomes are ten-fold higher in a home birth situation compared to in-hospital delivery, either by a repeated C-section or by vaginal birth after C-section (VBAC).

Almost one in 900 babies in such home births had a birth Apgar score of 0 and a slightly higher incidence of severe neurological complications such as seizures. This increases the risk for such babies by 11-12-fold compared to in-hospital births.

Breech babies also suffer a higher risk of death from home births, at 13.5 per 1000 live births.

The advantages of hospital birth are probably because of the ability to offer effective and immediate identification and intervention for numerous potentially or actually serious complications of childbirth, including those listed earlier.

These risks are higher in certain patient groups, such as first-time deliveries, elderly mothers (aged 35 years or above), those who are at or past 41 weeks of pregnancy, and those with a diagnosed breech presentation or a history of C-section. However, there is conflict between the medical and midwifery communities on the contraindications for home births, with the result that standardized exclusionary guidelines for home births are still awaited.

It is important to note that when high-risk patients are excluded, the outcomes for home births are good, but when high-risk patients are included, the neonatal mortality goes up more than eight-fold.

What are the implications?

Given that some women strongly prefer home births, it is essential to understand their motivations. Secondly, it is fundamental that midwives be integrated into the healthcare system completely. This requires standardized midwifery credentials, hospital privileges for accredited midwives, the ready availability of physicians and hospital facilities as a backup when required, open and respectful communication, and collaboration between healthcare professionals.

In short, the US birth system should be brought into line with other HICs where “both hospital and home-birth midwives are well-integrated into their country’s healthcare system.”

In helping patients understand the best birth choices open to them, the traditional medical ethics principles apply, such as:

• Beneficence (doing what is good for the patient, including natural birth if so desired and possible);
• Non-maleficence (or ‘first do no harm’), where the limits of possibility are defined in terms of the patient’s benefit, excluding out-of-hospital births when these would be harmful;
• Respect for patient autonomy when it does not require the professional to behave unprofessionally, such as not sharing information with the patient that would reveal the risks of home birth in certain situations, thus allowing the patient to opt for a risky birth when reasonable alternatives are available;
• Making recommendations when the benefits of a hospital delivery are clearly weightier than the risks
• Directive counseling when medically reasonable alternatives to a hospital delivery are lacking.

“Attending a planned home birth, especially when there are high-risk factors, regardless of training or experience, is not acting in a professional capacity because this results in clinically unnecessary and therefore clinically unacceptable perinatal risk.”

Along with such empowerment, the hospital healthcare system should be overhauled to offer pregnant women greater freedom regarding unnecessary interventions and procedures, providing compassionate care, and, for instance, allowing patients to opt for a trial of labor or vaginal breech birth when appropriate. Those who come in for a hospital birth following a failed home birth attempt are eligible for the same level of care and kindness as others who planned a hospital birth from the beginning.