ON No. 27

World Hlth Org. techn. Rep. Ser. 1950, 27

World Health Organization Technical Report Series

No. 27

EXPERT GROUP ON PREMATURITY

Final Report

WO RLD HEALTH ORGANIZATION

PALAIS DES NATIONS

GENEVA OCTOBER 1950

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The World Health Organization (WHO) is a specialized agency of the United Nations and represents the culmination of efforts to establish a single inter- governmental health agency. As such, it inherits the functions of antecedent organizations such as the Office International d'Hygiene Publique, the Health Organization of the League of Nations, and the Health Division of UNRRA.

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World Health Organization Technical Repo rt Series

No. 27

EXPERT GROUP ON PREMATURITY

Final Report

Geneva, 17- 21 April 1950

I .

Definitions

2. Suggestions for programme planning 3. Preventive programme

4. Programme for care .

5. Development of complete programme

6 . Educational programme for specialization in premature-

Page 3 5

5

9

infant care 9

7 . Research

0

8. Fellowships .

9. Information service

WOR LD HEA L TH O R GANIZAT IO N

PALAIS DES NATIONS GENEVA

OCTOBER 1950

EXPERT GROUP ON PREMATURITY Final Report

Members :

Dr L. Camacho, Obstetrician ; Chief, Maternal and Child Health Centre, Public Health Department, Quito, Ecuador

Dr Y. Mary Crosse, Paediatrician, Birmingham Regional Hospital Board, Birmingham, United Kingdom

Prof esseur M. Lelong, Clinique de Puericulture de Ia Faculte de Medecine de l'Universite de Paris, France

Dr S. Z. Levine, Professor of Paediatrics and Paediatrician-in-Chief, New York Hospital , Cornell Medical Center, New York City, N.Y., USA

(Chairman)

Miss E. Magnussen, Director, Nursing Division, National Health Service, Copenhagen, Denmark

Dr A. Ylppo, Professor of Paediatrics, University of Helsinki; Chief, Chil- dren's Clinic, Helsinki, Finland (Co-Chairman)

Adviser:

Miss D. Batt, Matron, Training Centre for Plunket Nurses, Dunedin, New Zealand

Secretary:

Dr Ethel C. Dunham, Consultant, Maternal and Child Health Section, WHO

The report on the meeting of this expert group was originally issued in mimeo-

graphed form as document WHO /MCH/20, 27 April 1950.

World Hlth Org. techn. Rep. Ser. 1950, 27

EXPERT GROUP ON PREMATURITY Final Report

T he Second World Health Assembly gave recognition to the importance of prematurity as a world health problem by adopting the WH O 1950 pro- gramme which included the convening of an expert group on care of the premature infant.

It is generally accepted that prematurity plays an important role in causing infant deaths . The need for expert advice was indicated by requests coming to WHO for assistance in developing and promoting plans for premature-care programmes and for information about various aspects of prematurity .

The Expert Group on P rematurity met in plenary sessions and in work- ing parties, in Geneva, from 17 to 21 April 1950 inclusive. It considered the following subjects and made suggestions and recommendations.

1. Definitions

The Expert Group on Prematurity recognizes the necessity for uniform terminology for international usage. Since the primary goal is to lower foetal and neonatal mortality, this aim can best be achieved by providing

1

I n accordance with the instructions of the Executive Board at its fifth session, an ad hoc committee examined this report and, acting on behalf of the Board, adopted the following resolution :

The ad hoc committee of the Executive Board I . NOTES the report of the Expert Group on Prematurity ; 2. AUTHORIZES itS publication ;

Taking into account the recommendations of the expert group in considering relevant items on its agenda,

3. TRANSMITS the present report to the Third World Health Assembly, and 4. POINTS ouT that recommendations of expert groups which concern WHO policy and operations remain recommendations unless and until they are implemented by the Executive Board or the World Health Assembly in adopting and putting into action the annual programme of WHO.

(Off. Rec. World Hlth Org. 28, Annex 2)

2

Off. Rec. World Hlrh Org. 18, 70; 21,

- 3 -

4

specialized care for infants of low birth-weight. The group suggests that a premature infant be defined as one whose birth-weight is 2,500 g.

(5¥2 pounds) or less. The limitations of this criterion are recognized, however, since data on birth-weight will not always be available and other criteria of prematurity must be used, for example, gestation period. The group therefore recommends the adoption by all countries for purposes of vital statistics of the international definition of the First World Health Assembly, which states:

For the purpose of this classification an immature infant is a liveborn infant with a birth-weight of 5% pounds (2,500 grams) or less, or specified as immature. In some countries, however, this criterion will not be applicable. If weight is not specified, a liveborn infant with a period of gestatiOn of less than 3 7 weeks or specified as "premature"

may be considered as the equivalent of an immature infant for purposes of this classi- fication.

T he terms "immature" and "premature" are here used interchange- ably. However, the group points out that the term "premature" is preferable to the term " immature " .

An infant with a birth-weight of 2,500 g. or less that shows any signs of life in accordance with the definition recommended by the WHO Expert Committee on Health Statistics (Subcommittee on the Definition of Still- birth and Abortion)

should be classified as a premature live birth. The group considered the question of setting a weight limit below which a pre- mature birth should be considered an abortion . The majority of the group agreed that no such limit should be set for two reasons : (a) the exact lower weight limit cannot be defined on the basis of present knowledge, and (b) such a delimitation would not be in line with recommendations of the above-mentioned subcommittee to define "foetal death" rather than

" stillbirth " and " abortion ".

An infant with a birth-weight of 2,500 g. or less that shows no signs of life, in accordance with the definition recommended by the above-men- tioned WHO subcommittee, should be classified as a premature foetal death.

3

World Health Organization (1948) Manual of the lllfernational Statistical Classifi- cation of Diseases, Injuries, and Causes of Death (Bull. World Hlth Org. Suppl.

Geneva,

p. 212

4

" Live birth is the complete expulsion or extraction from its mother of a product

of conception , irrespective of the duration of pregnancy, which, after such separation,

breathes or shows any other evidence of life, such as beating of the heart, pulsation of

the umbilical cord, or definite movement of voluntary muscles, whether or not the

umbilical cord has been cut or the placenta is attached ; each product of such a birth

is considered live born." (World Hlth Org. techn. Rep. Ser. 1950, 25, 12)

FINAL REPORT

5

2. S uggestions for Programme JPJanning

The group wishes to emphasize the importance of giving consideration to two types of programmes : (a) for lowering the incidence of p rematurity, and (b) for the care of prematurely born infants.

The group considered the prerequisites and content for undertaking each type of programme and recognized that the initiation of a preventive programme might well precede the initiatio n olf a specialized-care pro- gramme. Either type of programme may be iilltiated in a localized area or on a country-wide basis .

Setting up these requirements does not necessarily tend to deter less well-developed countries from developing prema.ture-infant programmes, but it is intended to encourage the establishment of general public-health measures and the strengthening of maternal and , child health programmes before embarking on a specialized programme ;aimed specifically at the reduction of premature-infant morbidity and mortality.

3. Preventive Programme 3. I Prerequisites

The group was of the opinion that a programme to reduce the incidence of prematurity may be introduced in a country ev•en if the p rerequisites for a specialized-care programme have r.ot yet been met.

The group outlined the following prerequisites :

(a) an actively working public-health organization with a well-developed maternal and child health section, including ad•equate numbers of well- qualified physicians, nurses,

and midwives;

(b) evidence of a steadily downward trend in infant mortality-rates;

(c) evidence that a programme is being develojped to educate the public as well as professional workers with respect to the need for a preventive programme;

(d) efforts made o r in progress to determine the chief causes in a parti- cular area before activating the preventive prog1ramme, if these are not already known ;

(e) attempts to ameliorate unfavourable social, economic, and hygienic conditions, including legislation for protection of pregnant women .i n industry and means for implementation of such l•egislation ;

6

Attention is called to the standards for the preparattion of nursing personnel set

up

the International Council of Nurses.

6

([) adequate provision for hospitalization of women with complications of pregnancy.

3.2 Content

The maximum results in any premature-infant programme can best be attained by lowering the

of prematurity, since even with the best of postnatal care there will still remain an irreducible but appreciable minimal premature-infant mortality-rate.

A difficult situation is presented, however, by inadequate knowledge of causes of premature birth. For this reason research programmes should be developed simultaneously with preventive programmes (see section 7).

There is sufficient knowledge to make it clear that a premature-infant programme will result in lowering the incidence of prematu re birth from certain known causes and will result in the prolongation of pregnancy, delivery of more mature infants and, thereby, the reduction of premature- infant mortality.

T he group suggests that a preventive programme should include the following:

3. 2. I Educational programme, stressing the importance of:

(a) early and continuous prenatal care ; availability of suc h care and the means for obtaining these services;

(b) maintenance during pregnancy of good health - nutritional, phy- sical, and mental.

3. 2. 2 Pro vision of services

(a) prenatal clinics providing medical, nursing, public-health, and social services ;

(b) hospitalization for pregnant women with complications;

(c) a well-o rganized delivery service, hospital or home;

(d) protection of the pregnant woman by means of:

(1) adequate legislation to promote physical rest and freedom from anxiety;

(2) provision of auxiliary services to make possible fulfilment of the

legislation.

FINAL REPORT

7

4. Programme for Care 4. I Prerequisites

In addition to the prerequisites already set forth for a preventive pro- gramme, the group outlined prerequisites for a specialized-care programme:

(a) birth registration as complete as possible and data on the birth- weight and/ or gestation period entered on the birth certificate, if possible;

(b) compilation of accurate infant-mortality statistics and neonatal and foetal mortality-rates ;

(c) significant downward trend in infant mortality, particularly in the period one month to one year ;

(d) qualified medical and nursing personnel ;

(e) adequate hospital faci)jties and equipment which are avai lable or can be made avai lable;

(f) provision for adequate services to improve unfavourable social conditions of pregnant women .

4. 2 Content·

I n areas in which there are no organized programmes for premature- infant care, the mortality-rate of these infants is high compared with those areas in which such programmes have been developed.

The initial steps in the development of a premature-infant care pro- gramme should be related to the pattern of maternity care in the country or area undertaking the programme, depending on whether the largest proportion of births is in hospitals or homes .

The group further suggests that these programmes might well be started as demonstrations. In such demonstration plans, efforts should be made to ensure that all existing resources of the community be integrated into the programme, including such resources as public-health and welfare agen- cies, official and voluntary, and professional personnel, including physi- cians, nurses, and midwives.

4 . 3 Hospital care

The group suggests the following minimum requirements for establish- ing a premature-infant hospital unit.

4. 3.1 Staff. At least one qualified physician, preferably a paediatrician

with experience in the care of new-born infants, both premature and full-

term, to be in charge of the unit.

8

At least one qualified nurse with special training in the care of pre- mature infants to supervise the nursing personnel in the unit.

Sufficient additional personnel to ensure adequate care for the infants at aU times (day and night).

4. 3. 2 Location of unit. In selecting the site for the premature-infant unit.

consideration should be given to providing protection from infection and easy access to mothers to encourage closer mother-baby relationship.

4.3.3 Facilities , equipment, and records. There should be a separate bed for each infant, and adequate facilities for band-washing, formula prepara- tion, transport, and for emergency treatment. If incubators are used, they should be safe for use with oxygen.

Medical and nursing records should be adequate.

4. 3.4 Parent-teaching and follow-up. Parent-teaching: this programme should begin while the mother is in the hospital. She should be permitted to participate in the care of her infant under nursing supervision. Parent- teaching should be continued in the home.

Follow-up: see paragraph (d) of section 4.4 .1.

4.4 Home-care programme

If a home-care programme seems desirable for a given area, it would function most satisfactorily if facilities for hospitalization were provided for sick premature infants and those of low birth-weight who require a highly specialized type of care.

Such a home-care programme will tend to encourage normal mother- child relationships and meet the emotional needs of both.

4.4.1 Requirements. The group suggests the following requirements for home care:

(a) staff: adequate professional and auxiliary personnel ; physicians to serve as medical advisers and consultants ; public-health nurses to appraise the suitability of the home, including the availability of proper facilities and equipment to carry out the parent-teaching programme ; home helpers to enable the mother to readjust to domestic responsibilities;

(b) facilities for transportation of staff' and of infants requiring hospita- lization;

(c) adequate medical and nu rsing records;

(d) arrangements for follow-up for medical care and assessment of

physical and mental status.

FINAL REPORT

9

5. Development of Complete Pwgramme

The initial programme, whether it be one of hospital or home care, should envisage attainment of higher standards and extension to increasingly larger areas as staff and facilities become available. It is suggested that a complete programme include :

5 . 1 Administration

(a) adequate financial resources;

(b) assessment of requirements for ( I) hospital beds,

(2) home-care service ;

(c) case-finding, including a prenatal programme and prompt reporting of premature births;

(d) transport service;

(e) integration with other public-health and welfare services, especially maternal and child health services ;

([) follow-up care.

5. 2 Medical, nursing, and social services for hospital and home care It is urged that a country should aim at a sta ndard of three nurses to four infants (for the 24-hour period), on the basis of an 8-hour working day.

It is also urged that the ratio of trained nurs,es to auxiliary nurses be maintained as high as possible.

5. 3 Educational programmes, for professio nal pt;:rsonnel and the public.

5 .4 Re search, including analysis of vital statistic:s (see section 7).

6. Educational Programme for Sp,ecialization in Premature-Infant Car1e

There js a need for development in some areas , and expansion in others,

of training programmes for physicians, nurses, amd midwives jn the spe-

cialized fie ld of premature-infant care. A country initiating a premature-

infant care programme is urged to consider as a prerequisite a good general

training, including paediatrics, obstetrics, and public health for physicians,

nurses, and midwives.

10

6.1 Content

The group suggests that the content of the specialized educational pro- gramme should include :

(a) practical experience, under qualified direction and supervision, in a well-organized and equipped centre for premature-infant care, with hospital, home, and follow-up services ;

(b) instruction in and demonstration of generally accepted techniques of premature-infant care. The duration of the courses will depend on the individual needs of the professional group concerned . In-service training and frequent refresher courses for physicians, nurses, and midwives who are already engaged in premature-infant care.

In order to promote team spirit, it is suggested that courses be organized for the joint participation of both medical and nursing personnel for at least some of the period. It is further suggested that there is a great advantage if a team of a doctor and one or more nurses working in the same centre takes the course together.

It is emphasized that there should be exchange of personnel, both medical and nursing, from centres for premature-infant care within the country or from abroad. This applies directly to a new pilot project, for which it will be necessary to have staff trained at a centre within the country or abroad.

7. Research

The group, with full realization of the many gaps in current knowledge of all aspects of prematurity, did not consider it within its scope to present, in detail, specific research programmes. The group believes, however, that it will be of value to present examples of the types of research that are urgently needed :

(a) the setting-up, in selected areas, of study-groups to correlate the gestation period with birth-weight and other anthropometric as well as anatomical and physiological criteria of prematurity. It is suggested that these investigations should take into consideration various weight-group- ings in relation to these other criteria ;

(b) a study ofthe nutritional status of pregnant women to determine the effects of malnutrition on prematurity. Studies previously reported have not been conclusive ;

(c) studies of the causes of premature birth : the need for such studies

is indicated by the fact that in about half of the cases of premature birth

the causes are reported as unknown ;

FINAL REPORT

I I

(d) studies of the relation of social and economic factors to the inci- dence of premature births and deaths.

The group points out that the studies mentioned above, paragraphs (a) and (b), are considered suitable to be incorporated in the plans for WHO

health demonstration areas. ·

8. Fellowships

Finally, the group urges national governments to consider awarding fellowships for research and study in order to promote progress in the knowledge of prematurity and the improvement of methods of care of the premature infant.

9. Information S ervice

The group adopted the following resolution :

T he Expert Group on Prematurity

RECOMMENDS

that WHO develop an information service on prema- t u rity, such a service to include:

(a) collection of i nformation on prematurity (b) compilation of such data

(c) distribution of such information on request or through the medium of WHO publications

(d) advisory service on sources of information.

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