The modern concept of palliative care (PC) has been gaining momentum in recent decades, especially since the 1960s, in response to a realisation that end-of-life issues for seriously ill patients have been inadequately addressed with traditional approaches [1]. The focus on adult PC has reach such relevance that it has become a global public health priority [2].

Although in a slower fashion the concept of PC has been gradually incorporated into neonatology. Only recently it has been accepted that pain and discomfort can affect newborns, whatever their gestational age, and even foetuses [3, 4], despite the fact that attention was drawn to this issue already many years ago [5–8]. Likewise, the experience gained in the development of hospices, once again initiated for adults [9] and subsequently adapted to paediatrics and neonatology [10, 11], has provided insights towards the PC model applicable to perinatal medicine. The variety of PC approaches has introduced complexity and depth to the concept of PC in perinatal care, which makes necessary some degree of standardization.

Therefore, the objectives of this study were: first, to systematically review the clinical literature on Neonatal Palliative Care (NPC) and Perinatal Palliative Care (PPC) to determine if there is a best model of care; second, to summarise the evolution of the main traits of PPC; and lastly, to identify the most relevant features of PPC currently offered around the world.

In total, 1558 titles and abstracts were retrieved and assessed; there was not a single experimental study that fulfilled the eligibility criteria. Therefore, we classified and examine all the articles that met the remaining criteria, regardless of the study design. The articles were classified according to type of article or design as follows: comments or reflections 50, clinical studies 30 (case reports 15, quantitative series 10, and qualitative series 5), guidelines/clinical practice proposals 11, papers designing/describing a PC programme 5, and reviews 5. According to their place of origin 64 articles were from the USA (mainly from California 11, and Wisconsin 7); 25 from Europe (mainly from the UK 11, France 4, and Germany 3) and the rest were from Australia and New Zealand 6; Canada 4; Hong Kong 1 and Saudi Arabia 1. No quantitative empirical research studies were found, whether experimental (e.g. randomised controlled trials) or observational (cohort, or case-control studies).

Qualitative analysis of the content of the articles showed that the concept of PC has developed gradually; over time, there is a progression in the characterization of the care and consideration of issues that had not been initially addressed. Although the development is not perfectly defined--the various aspects of PC are inter-related and overlap--it can be summarised as follows: a) pain relief; b) comfort (multisensorial context); c) maternal bonding (and other emotional aspects); d) family-centered care; e) comprehensiveness (including psychological, social and spiritual aspects); f) early start and integrative care (including bereavement); g) antenatal period (see Figure 2).

The field of neonatal and perinatal medicine has been affected by the general interest shown in PC. The first references in the literature referring to the concept as such date to 1982 [11, 38], although its origins actually go back to the reaction to therapeutic obstination with premature births at the limit of viability in the early 1970s [39]. However, it should be pointed out that very few clinical studies can be found that can provide empirical data on PC in the perinatal setting. About half of the 101 articles identified were comments/reflections, and less than a third could be considered to be clinical contributions or studies, of which half were simply case reports. Of the clinical contributions, five were classified as primarily qualitative studies [31, 40–43], although in some other articles qualitative techniques were used. It was finally decided to classify these five studies, despite the fact that their main aim was not to study PC but to analyse the decision-making process of couples faced with the diagnosis of an unhealthy or non-viable foetus. In contrast, three other qualitative studies by Swanson-Kauffman that focused on the experience of miscarriage and the caring needs of women who miscarry were not included in the classification.

Interest in neonatal/perinatal PC seems to be greater in the USA (followed by Europe) than in other parts of the world, although this distribution may reflect a publishing bias that is influenced by the databases consulted and the lack of clinical literature from some parts of the world, such as Africa. However, it should be borne in mind that sociological and clinical practice differences may imply underlying different meanings regarding PC and end of life issues.

This study has certain limitations, the greatest of which is a lack of evidence-based empirical studies to identify the best model for perinatal PC. Much of the information has not been published in the traditional literature; rather, it is compiled in reports and protocols of clinical practice, which are not immediately available (except a few which are available online [44]) and could introduce some level of publication bias. Given the nature of the articles and the lack of quantitative results, we did a consensus analysis which would allow us to summarize the evolution of PC.

The qualitative evaluation of these articles seems to show an evolution on PPC over time that includes some of the aspects that have also been developed in newborn care. In addition, the care provided has also been enriched by input from palliative care units for adults and children. So the initial care provided for the more physical aspects such as pain relief and comfort (in a multisensorial context) is immediately supplemented with the importance of maternal bonding and other emotional aspects [45]. In this regard, the hospice model, as the precursor/pioneer of PC, has made a considerable contribution. Hospices emerged as a result of the work by Saunders with adults in the 1960s [9] and were soon advocated for children by Saunders herself [10] and then adapted for neonates by Whitfield [11]. Experience has also shown that general care designed not only to minimise pain in neonates but also to make them more comfortable, promote individualised developmental care [6] and facilitate bonding with the mother can also be of great relevance [7, 8]. The importance of family participation in the NICU, which found expression in the concept of "family-centered care" in the 1960s and 1970s [7, 46] also could have some influence on neonatal PC [1, 19, 33, 36, 37, 47]. Although PC emerged in close combination with the NICUs [47], to encourage incorporation of the process in the family environment, the possibility of PC taking place in the home (at least on a temporary basis) was considered [32, 48]. This option, however, would depend heavily on the professional support that could be provided and the changing circumstances of the patient and the family [45].

Recently, attention has been drawn to the need for "integrative care" [14]. Using this term, Milstein highlights the importance of introducing healing and palliation (when indicated) alongside curative measures as soon as any diagnosis, especially a critical one, is made as an integrative paradigm of care. He also points out that because loss can be experienced in many conditions, even in the absence of death, bereavement is represented as an on-going, continual process throughout a disease process.

In recent years, particular emphasis has been put on the importance of initiating PC early, even antenatally [1, 13, 33, 37]. Three general areas of implementation have been described [49]: foetus/neonates with lethal congenital anomalies, neonates that are previable or at the limits of viability, and neonates that do not respond to aggressive medical management.

An excellent synthesis of the design and implementation of a programme of this sort [11, 13, 37, 50] can be found in the document drawn up by the British Association of Perinatal Medicine, coordinated by Murdoch and entitled "Framework for clinical practice in perinatal medicine". It divides PC planning into eight stages: a) eligibility of foetus or baby for palliative care; b) family care (including psychological support, creating memories, support of spiritual/personal belief and social support); c) communication and documentation; and d) flexible parallel care planning. The next four stages represent points of care transition: e) pre-birth care; f) transition from active postnatal care to supportive care; g) end-of-life care; and h) post end-of-life care [51].