Transfer is the ordinary case, not the emergency
In the largest study ever done, 45 out of every 100 women having a first baby who planned to give birth at home were transferred at some point, and 35 in 100 were transferred before the birth. For later babies it was 12 in 100 and 6 in 100.
Most women planning a home birth expect to give birth at home. That is what the plan is. The single number that gets left out of that expectation is how often the plan changes, and it depends almost entirely on whether this is your first baby.
From the English Birthplace study, among women who planned a home birth:
| Planned home birth | First baby (n = 4,568) | Later baby (n = 12,256) |
|---|---|---|
| Transferred before the birth | 1,605 (35.1%) | 782 (6.4%) |
| Transferred after the birth | 407 (8.9%) | 639 (5.2%) |
| Transferred at all | 2,057 (45.0%) | 1,472 (12.0%) |
ACOG gives a similar range for the American picture: The reported risk of needing an intrapartum transport to a hospital is 23-37% for nulliparous women and 4-9% for multiparous women. Most of these intrapartum transports are for lack of progress in labor, nonreassuring fetal status, need for pain relief, hypertension, bleeding, and fetal malposition.
A systematic review of fifteen Western studies found total transfer rates ranging from 9.9% to 31.9%, with emergency transfers ranging from 0% to 5.4%. Those are ranges across studies, not an average, because the reviewers judged the studies too different to pool.
American registries report lower figures than the English study, for planned home births in low-risk pregnancies: intrapartum transfer in 4,473 of 42,778 (10.5%) in one registry and 7.7% in another, with urgent intrapartum transfer at 1.9% and 0.7%. The second registry's published transfer counts do not divide out to its published transfer percentages, so those two rates are given here as the source printed them, without their counts. In an older registry of 16,924 women who planned a home birth when labor started, 89.1% gave birth at home, meaning about 11 in 100 did not.
Why women transfer is the reassuring part. From the English data, among 3,529 women transferred from a planned home birth:
| Main reason | Number transferred | Share of transfers |
|---|---|---|
| Labor taking too long | 1,144 | 32.4% |
| Meconium in the waters | 432 | 12.2% |
| Repair of a perineal tear | 386 | 10.9% |
| Abnormal fetal heart rate | 246 | 7.0% |
| Retained placenta | 250 | 7.0% |
| Request for an epidural or spinal | 180 | 5.1% |
| Concern about the baby after birth | 180 | 5.1% |
| Other | 711 | 20.1% |
The commonest reason for transfer is not the one women fear. About a third of transfers are because labor is taking too long. The one that is time-critical is the 7.0% for an abnormal fetal heart rate.
How long a transfer takes. The only published timing data comes from England, inside the NHS, with NHS ambulances and an agreed receiving unit. Among 27,842 low-risk women planning birth at home or in a freestanding unit, the median time from the decision to transfer to the first assessment in a hospital labor unit was 49 minutes from home. For transfers before the birth for potentially urgent reasons it was 42 minutes. Adverse outcomes for the baby occurred in 1% to 2% of transfers among women who gave birth within an hour of the transfer.
Transfers from home or FMU commonly take up to 60 minutes from decision to transfer, to first assessment in an OU, even for transfers for potentially urgent reasons. Most transfers are not urgent and emergencies and adverse outcomes are uncommon, but urgent transfer is more likely for nulliparous women.
ACOG is direct about the absence of a threshold: Even in regions with integrated care systems, increasing distance from the hospital is associated with longer transfer times and the potential for increased adverse outcomes. However, no specific thresholds for time or distance have been identified.
If anyone offers you a safe distance or a safe number of minutes, they invented it.
ACOG also has something to say about how you should be treated when you arrive: When antepartum, intrapartum, or postpartum transfer of a woman from home to a hospital occurs, the receiving health care provider should maintain a nonjudgmental demeanor with regard to the woman and those individuals accompanying her to the hospital.
If that is not what happens to you, it is a departure from the current American position, not a personal failing of yours.
"What are the three commonest reasons you have transferred someone?"
"How long does it take, from you deciding, to me being assessed at the hospital? Have you timed it?"
"Do you come with me, and do you stay?"