Thank you for the link Ashbrant. Here is the methodology from the manuscript. I'll post my comments below.
Methods
Abstract
Introduction
Methods
Results
Discussion
References
The competency based process of the North American Registry of Midwives provides a certified professional midwife credential, primarily for direct entry midwives who attend home births, including those educated through apprenticeship. Our target population was all women who engaged the services of a certified professional midwife in Canada or the United States as their primary caregiver for a birth with an expected date of delivery in 2000. In autumn 1999, the North American Registry of Midwives made participation in the study mandatory for recertification and provided an electronic database of the 534 certified professional midwives whose credentials were current. We contacted 502 of the midwives (94.0%); 32 (6.0%) could not be located through email, telephone, post, or local associations, 82 (15.4%) had stopped independent practice, and 11 (2.1%) had retired. We sent a binder with forms and instructions for the study to the 409 practising midwives who agreed to participate.
Data collection
For each new client, the midwife listed identifying information on the registration log form at the start of care; obtained informed consent, including permission for the client to be contacted for verification of information after care was complete; and filled out a detailed data form on the course of care. Every three months the midwife was required to send a copy of the updated registration log, consent forms for new clients, and completed data forms for women at least six weeks post partum. To confirm that forms had been received for each registered client, we linked the entered data to the registration database. We reviewed the clinical details and circumstances of stillbirths and intrapartum and neonatal deaths and telephoned the midwives for confirmation and clarification. To verify this information we obtained reports from coroners, autopsies, or hospitals on all but four deaths. For these four, we obtained peer reviews.
Validation and satisfaction
We contacted a stratified, random 10% sample, of over 500 mothers, including at least one client for every midwife in the study. The mothers were asked about the date and place of birth, any required hospital care, any problems with care, the health status of themselves and their baby, and 11 questions on level of satisfaction with their midwifery care.
Data analysis
Our analysis focused on personal details of the clients, reasons for leaving care prenatally, the rates and reasons for transfer to hospital during labour and post partum, medical interventions, health and admission to hospital of the newborn or mother from birth up to six weeks post partum, intrapartum and neonatal mortality, and breast feeding. We compared medical intervention rates for the planned home births with data from birth certificates for all 3 360 868 singleton, vertex births at 37 weeks or more gestation in the United States in 2000, as reported by the National Center for Health Statistics,10 which acted as a proxy for a comparable low risk group. We also compared medical intervention rates with the listening to mothers survey,5 a national survey weighted to be representative of the US birthing population aged 18-44. Intrapartum and neonatal death rates were compared with those in other North American studies of at least 500 births that were either planned out of hospital or comparable studies of low risk hospital births.
Results
Abstract
Introduction
Methods
Results
Discussion
References
A total of 409 certified professional midwives from across the United States and two Canadian provinces registered 7623 women whose expected date of delivery was in 2000. Eighteen of the 409 midwives (4.4%) and their clients were excluded from the study because they failed to actively participate and had decided not to recertify or left practice. Sixty mothers (0.8%) declined participation. The figure provides an overview of why women left care before labour and their intended place of birth at the start of labour.
Characteristics of the mothers
We focused on the 5418 women who intended to deliver at home at the start of labour. Table 1 compares them with all women who gave birth to singleton, vertex babies of at least 37 weeks or more gestation in the United States in 2000 according to 13 personal and behavioural variables associated with perinatal risk. Women who started birth at home were on average older, of a lower socioeconomic status and higher educational achievement, and less likely to be African-American or Hispanic than women having full gestation, vertex, singleton hospital births in the United States in 2000.
Transfers to hospital
Of the 5418 women, 655 (12.1%) were transferred to hospital intrapartum or post partum. Table 2 describes the transfers according to timing, urgency, and reasons for transfer. Five out of every six women transferred (83.4%) were transferred before delivery, half (51.2%) for failure to progress, pain relief, or exhaustion. After delivery, 1.3% of mothers and 0.7% of newborns were transferred to hospital, most commonly for maternal haemorrhage (0.6% of total births), retained placenta (0.5%), or respiratory problems in the newborn (0.6%). The midwife considered the transfer urgent in 3.4% of intended home births. Transfers were four times as common among primiparous women (25.1%) as among multiparous women (6.3%), but urgent transfers were only twice as common among primparous women (5.1%) as among multiparous women (2.6%).
Medical interventions
Individual rates of medical intervention for home births were consistently less than half those in hospital, whether compared with a relatively low risk group (singleton, vertex, 37 weeks or more gestation) that will have a small percentage of higher risk births or the general population having hospital births (table 3). Compared with the relatively low risk hospital group, intended home births were associated with lower rates of electronic fetal monitoring (9.6% versus 84.3%), episiotomy (2.1% versus 33.0%), caesarean section (3.7% versus 19.0%), and vacuum extraction (0.6% versus 5.5%). The caesarean rate for intended home births was 8.3% among primiparous women and 1.6% among multiparous women.
Outcomes
No maternal deaths occurred. After we excluded four stillborns who died before labour but whose mothers still chose home birth, and three babies with fatal birth defects, five deaths were intrapartum and six occurred during the neonatal period (see box). This was a rate of 2.0 deaths per 1000 intended home births. The intrapartum and neonatal mortality was 1.7 deaths per 1000 low risk intended home births after planned breeches and twins (not considered low risk) were excluded. The results for intrapartum and neonatal mortality are consistent with most North American studies of intended births out of hospital11-24 and low risk hospital births (table 4).
Breech and multiple births at home are controversial among home birth practitioners. Among the 80 planned breeches at home there were two deaths and none among the 13 sets of twins. In the 694 births (12.8%) in which the baby was born under water, there was one intrapartum death (birth at 41 weeks, five days) and one fatal birth defect death.
Apgar scores were reported for 94.5% of babies; 1.3% had Apgar scores below 7 at five minutes. Immediate neonatal complications were reported for 226 newborns (4.2% of intended home births). Half the immediate neonatal complications concerned respiratory problems, and 130 babies (2.4%) were placed in the neonatal intensive care unit.
Health in first six weeks post partum
Health problems in the six weeks post partum were reported for 7% of newborns. Among the 5200 (96%) mothers who returned for the six week postnatal visit, 98.3% of babies and 98.4% of mothers reported good health, with no residual health problems. At six weeks post partum, 95.8% of these women were still breast feeding their babies, 89.7% exclusively.
Outcome validation and client satisfaction
Among the stratified, random 10% sample of women contacted directly by study staff to validate birth outcomes, no new transfers to hospital during or after the birth were reported and no new stillbirths or neonatal deaths were uncovered. Mothers' satisfaction with care was high for all 11 measures, with over 97% reporting that they were extremely or very satisfied. For a subsequent birth, 89.6% said they would choose the same midwife, 9.1% another certified professional midwife, and 1.7% another type of caregiver.