This 6-year follow-up study, post the MidU Trial [14] (2008–2013), and 10 years since the introduction of MLUs in Ireland, demonstrates ongoing support for midwife-led care as a safe and viable option for healthy, low-risk pregnant women. During the study period, the antenatal transfer rate, from the MLU to the CLU, decreased and more women who opted for MLU care started their labour at the MLU. Rates of instrumental births remained low, rates of interventions and complications were also low, and very few babies needed neonatal intensive care. Births at the MLU were characterised by a high number of women giving birth in upright positions, having few carers (greater continuity of care), experiencing few vaginal examinations, and having the third stage of labour managed physiologically. Other interventions, such as amniotomy and episiotomy, also decreased over time. Collectively, these results reinforce the results of international literature that suggests midwife-led childbirth care is a safe option that supports normality in labour and birth.
Although the transfer rate, overall, was stable over the years, the decreasing antenatal transfer rates suggest that more women were enabled to start labouring at the MLU and, instead, were transferred during labour to the CLU as needed. The greater numbers of nulliparous women requiring intrapartum transfers, might be reflective of the greater number of nulliparous women accessing the MLU over the years, rather than ‘true’ increases, although, intrapartum transfers also increased in multiparous women (Table 2). Intrapartum transfer is often a sub-optimal/negative experience for women [11] causing maternal anxiety. However, the MLU and the CLU are situated in the same building and belong to the same care organisation. This leads to an easier transfer during labour for most women, and transfers are managed with limited inconvenience. Increases in the intrapartum transfer rates over the study period, may reflect, in part, overall increasing intervention in childbirth, for example, increasing rates of induction and acceleration of labour [16, 17], in maternity care, in general.
For the group of women who remained in the MLU throughout pregnancy and birth, the maternal and neonatal outcomes showed low rates of sphincter tears, high rate of intact perineum, low rate of PPH, and very few babies with low Apgar scores, in accordance with previous research [1, 18]. Furthermore, these women had very good outcomes in terms of the care they received, such as few carers, few vaginal examinations during labour, and increased physiological management of the third stage of labour. Therefore, for these women with low risk, MLU care seemed to reduce the risk of unnecessary interventions.
Interventions such as amniotomy and episiotomy are often used routinely during birth without showing positive outcomes [19, 20]. These interventions, when compared in women who had spontaneous vaginal births at the MLU and women who had spontaneous vaginal births at the CLU, were found to be much more common in the CLU, corroborating earlier research [5, 12, 17, 18, 21]. Some of these differences might be explained by risk factors occurring during labour and birth but do not explain the large differences in both primiparous and multiparous women (Table 5). The most common reason for intrapartum transfer was meconium-stained liquor and/or fetal heart rate abnormalities, which would not necessarily affect the amniotomy and episiotomy rates, nor should they affect the rate of physiological management of the third stage of labour. It is thus likely, that the difference in rate of interventions in women with spontaneous vaginal birth is due to different care philosophies in the different units [22]. The increased rate of interventions in the CLU did not seem to result in important differences in outcomes such as PPH, Apgar score less than 7 and sphincter tear rates, which were similar across the units or slightly lower, only, in the MLU births. The reduced rates of PPH in the MLU are interesting as half of all women in MLU had a physiological management of the third stage, in line with recommendations for low risk women [23].
Quality in childbirth care [10] can be examined with care variables such as maternal position for birth [24], number of carers and number of vaginal examinations. All of these care indicators were lower in the MLU, showing that providing care in MLUs is one way to improve the quality of childbirth care for healthy, low risk women [2, 5]. Being able to choose a comfortable position may influence the birth experience for women and using a variety of birth positions indicates that birthing women have more influence and control over their births [24] and may explain why women are more satisfied with midwife-led care [1, 2, 5, 15]. A low rate of vaginal examinations could also be used as a quality of care indicator because they are often experienced as uncomfortable and do not benefit the progress of labour [25].
It has taken a long time for Ireland to reach acceptance, and permit the introduction, of midwife-led care [26]. However, given the continued positive outcomes of midwife-led care demonstrated here, in addition to the successful and cost-effective outcomes of the previous trial [14, 15], and international literature [2], it is clear that midwife-led care should now be extended to other units in the country. The recent Maternity Strategy, launched in 2016 [27] defines a supported care pathway, as one “intended for normal-risk mothers and babies, with midwives leading and delivering care within a multidisciplinary framework”. Thus, there is no barrier to the roll-out of birth centres led by midwives, across Ireland.
Strengths and limitations
Limitations of this study include the retrospective design, and, the potential influence of factors, other than those reported, on care during labour and birth in the compared groups who had a spontaneous vaginal birth at MLU and CLU. In the group that birthed spontaneously at the CLU, (having transferred from the MLU), some would have been transferred from MLU care due to risk factors and some only because the MLU was at capacity. These data, therefore, are not comparable with the group that birthed spontaneously at the MLU, especially women who were transferred due to prolonged labour who would have had interventions at the CLU. However, episiotomy, maternal position for birth, number of carers, number of vaginal examinations, and physiological management of third stage are not always directly influenced by obstetric risk factors.
The study sample included in this study are representative of the study’s target population (that is, all low risk women attending the two MLUs in Ireland during the study period) because the MLU chosen for this study was larger than the second MLU by approximately 2.5 times in terms of the number of births per annum and the numbers attending the MLUs on a monthly or annual basis. For this reason, we are confident that the study sample size was sufficiently large to allow for the results to be generalised and for inferences to be made to the wider target population.
