Prevention Of Prematurity Research Articles

Prevention of prematurity

Although only about 8 per cent of pregnancies end prematurely, as much as 75 per cent of perinatal deaths are due to prematurity. Since it is difficult to identify the predisposing factors in individual cases and to prevent the premature onset of labor, it is necessary to try to arrest such labor when it occurs. A theoretical scheme for the mechanism of labor in the human subject is presented. This permits the identification of four possible points of attack: (1) replacement of progesterone to reduce the myometrial sensitivity to oxytocin, (2) administration of β-mimetic agents to relax the uterus and make it unresponsive to stimuli, (3) administration of ethanol to block oxytocin secretion, and (4) administration of anti-inflammatory drugs to inhibit prostaglandin synthesis. Results obtained with ritodrine, a β-mimetic agent, and with ethanol are presented as illustration. Ritodrine gave somewhat better results than ethanol, possibly because the treatment was continued after discharge of the patients.

PROLONGED “GESTATION” FOLLOWING FETECTOMY IN MONKEYS

A fetal influence over gestation time is recognized in several mammals; clarification of the mechanisms involved might suggest approaches to the prevention of prematurity. Fetal pituitary or adrenal defects lead to prolonged gestation, and ACTH or glucocorticoid administration can induce premature labor. We have attempted to distinguish fetal and placental mechanisms by performing fetectomy in macaques. Fetuses were removed from 10 monkeys at gestation ages from 65 to 143 days; placentas were left in situ. Of the 10 placentas, 7 were carried past normal term (155-176 days), and were delivered at 181 to 243 days. Four were delivered spontaneously and 2 after giving dexamethasone; 1 was removed surgically. At fetectomy, plasma progesterone values were highest in the umbilical vein, lower in fetal heart and uterine vein, and lowest in maternal peripheral vein. Following fetectomy, maternal progesterone values remained at or above normal pregnancy levels until placental expulsion or shortly before. Following expulsion, values fell promptly to non-pregnancy levels. Estradiol values (5 animals) fell within 7 to 19 days after fetectomy to 1/3 of pre-fetectomy levels and the rise normally seen before delivery did not occur prior to expulsion. These results indicate that in the absence of the fetus, delivery of the placenta is usually delayed, but that the ability of a glucocorticoid to precipitate expulsion remains. Maternal plasma progesterone levels are maintained, but estradiol levels fall.

Management of High Risk Pregnancy and Intensive Care of the Neonate

same problems through the eyes of a pediatrician in the second half? For example, the evaluation of fetal growth and fetal age is first encountered in the obstetric section. The pediatric presentation of the same problem, with the same chart, reappears 75 pages later. Although this may be the most complete discussion in the book the statement in the obstetric chapter with cross-reference to the pediatric chapter does not satisfactorily fulfill any definition of perinatology. Those concerned about the modern newborn nursery also recognize the need to break down the barriers which arbitrarily separate the members of the health team caring for the infant through the perinatal period. If this is in fact a realistic goal then the goal is not achieved by the discussion which divides the in¬ tensive of the newborn infant under the headings of physician care and nursing responsibility. The second edition has increased by 60% in both size and price over the previous edition. A resume of the ad¬ ditions to this edition provides a re¬ vealing tally of the changes that have occurred in fetal and neonatal man¬ agement between 1966 and 1971. The discussions of intrauterine and post¬ natal assessment of fetal growth, evaluation of fetal distress, prenatal detection of genetic defects, and management of erythroblastosis have either been added or expanded vastly. New additions include discussions of assisted respiration, intravenous hyperalimentation, arterial puncture, umbilical artery catheterization and phototherapy. The current and impor¬ tant topics of regional neonatal in¬ tensive and transportation of the critically ill newborn are passed over lightly and deserve greater promi¬ nence. The introduction of a discus¬ sion of pulmonary oxygen toxicity and the expanded discussion of retrolental fibroplasia provide a word of caution which is self-evident. The in¬ creased concern regarding sequelae of prematurity, the responsibilities of the social worker, and the prevention of prematurity with a discussion of problems of planned pregnancies and abortion broaden the perspective of the total problem of newborn care. The presentation itself maintains the format of the previous edition, with information presented in didac¬ tic tabular form. This is not a book which answers the question why but addresses itself to the question how. Although objection to this ap¬ proach has previously been raised, its widespread acceptance indicates that the need for such a book exists. Hav¬ ing accepted this format the need for accuracy then becomes essential, and is the single basis on which the merits of this book must be judged. Errors of omission and of fact are unaccep¬ table. Unfortunately the optimal man¬ agement for all clinical problems can¬ not always be defined. To be concise requires an objective synthesis of cur¬ rent knowledge when it is available, combined with mature personal judg¬ ment of unsettled questions. Dis¬ agreement with recommendations in these uncertain areas is permissible and cannot be viewed as a con¬ demnation. As examples, many read¬ ers may disagree with the recommen¬ dations that infants with meconium aspiration require treatment with an¬ tibiotics, or that antibiotic ointment should be applied to the umbilical stump following umbilical catheter¬ ization, or that vitamin E should be added daily to the formula, or that al¬ bumin should be administered before and after exchange transfusion, or that hydrocortisone is indicated in the treatment of sclerema. The con¬ clusion that current intensive in¬ cubators offer the protective environ¬ ment necessary for optimal is certainly questionable. More serious objections can be raised regarding omissions and inaccuracies of more firmly established recommendations. The discussions of life-threatening but curable illnesses such as polycythemia, twin-to-twin transfusion, narcotic withdrawal, and hypogly¬ cemia are either scattered so dif¬ fusely throughout the book or are so scanty as to be of little help to the uninitiated for whom this book is in¬ tended. The role of cord blood screen¬ ing for elevated macroglobulin levels is barely mentioned. Examples of factual errors include statements in¬ dicating that no placental lesions diagnostic of cytomegalic inclusion disease have been described; the ad¬ ministration of chloramphenicol to a patient with glucose 6-phosphate dehydrogenase (G6-PD) deficiency may induce megaloblastic anemia; chlor¬ amphenicol may induce fetal hepatotoxicity; excluding drug related re¬ sponses, the effect of maternal hyperthyroidism on fetal thyroid function is ignored; when term is reached the conjugating mechanism of the fetus for bilirubin is mature. Finally the typographical errors are a nuisance and at times could be confusing or

Prevention of Prematurity

Prevention of Prematurity

High-risk pregnancy. I. Prevention of prematurity the sine qua non for reduction in mental retardation and other neurologic disorders: Clifford: p. 243

High-risk pregnancy. I. Prevention of prematurity the sine qua non for reduction in mental retardation and other neurologic disorders: Clifford: p. 243

Placenta previa: An evaluation of expectant management and the factors responsible for fetal wastage

1.1. Two hundred and twenty-six cases of placenta previa with a total perinatal mortality rate of 12.4 per cent are reviewed.2.2. The fetal mortality rate in the 123 cases of partial placenta previa was 5.7 per cent and 20.4 per cent in the 103 cases of total placenta previa.3.3. The factors responsible for the perinatal wastage are discussed.4.4. A uterine incision through the placental site does not appear to increase the perinatal loss.5.5. Expectancy offered no advantages to 45 per cent of the cases because the infant was of term size. In another 21 per cent, despite prematurity, maternal and fetal indications dictated immediate delivery.6.6. Expectant management was feasible in only 34 per cent of the cases. In this group, expectancy increased the perinatal salvage so that it approximated that of the immediately treated group.7.7. Thus, two decades after the introduction of expectant management, the problem of prevention of prematurity and intrauterine anoxia still remains.

The prevention of prematurity in multiple pregnancy

It has been shown that in a patient who has a multiple pregnancy that early diagnosis, preferably by fetal electrocardiography followed by bed rest, will materially decrease the usually high incidence of prematurity in this condition. A plea is made for the increased use of fetal electrocardiography in all patients in whom the diagnosis of multiple pregnancy is suspected.

Extra-amniotic cesarean section in the prevention of fatal hyaline membrane disease: A continuing cooperative San Diego study

A N Y A T T E M P T to prevent hyaline membrane disease or the respiratory distress syndrome is of paramount importance to the obstetrician and his patients. The pediatrician remains frustrated in his treatment of this disease. The obstetrician’s attack on prematurity has been equally frustrating. Since little advance has been made in the successful prevention of prematurity, perhaps the attack should be transferred to the preventive support of the premature child. One method of supporting the premature child might be the prevention of contamination of fluids aspirated by the child at birth. Little preventive support can be given a premature child delivered vaginally after membranes have been ruptured. On the other hand, all published reports emphasize a higher incidence of hyaline membrane disease in all children delivered by cesarean section. This is particularly true in premature babies. Snyde? suggested that the cause of hya-

2S38. MINISTRY OF HEALTH (GREAT BRITAIN), CENTRAL HEALTH SERVICES COUNCIL. Report of the Sub-Committee on the Prevention of Prematurity and the Care of Premature Infants

2S38. MINISTRY OF HEALTH (GREAT BRITAIN), CENTRAL HEALTH SERVICES COUNCIL. Report of the Sub-Committee on the Prevention of Prematurity and the Care of Premature Infants

Handicapped Children—Problems, Programs, Services—in Michigan

This publication is a compilation of papers presented at the Conference on Handicapped Children in Michigan, conducted from February 20 to 21, 1961, under the auspices of the Michigan Crippled Children Commission in collaboration with the Division of Maternal and Child Health of the Michigan Department of Health. The conference was conducted primarily to provide information needed by health officers and supervisory or senior nurses in handling problems arising in their local health units of Michigan. Several introductory papers deal with the handicapped as a public health problem and point out current problems and the scope and availability of services in the State of Michigan. The majority of papers are concerned with problems which result from cleft lip and cleft palate, prevention of prematurity through public health programs, and proper care of premature infants. The final group of papers concerns blindness, sight conservation, and a symposium on reading readiness. The

DUNHAM'S PREMATURE INFANTS

In 1948, the Children's Bureau issued publication No. 325 entitled Infants. It was written by Dr. Ethel C. Dunham, and it quickly became an international guide for professional workers concerned with the prevention and management of prematurity. A second edition was required in 1955; and in 1961 a third edition was prepared by Dr. Silverman. This new edition, expanded and enriched, is divided into three major sections which, when taken together, provide a comprehensive and readable survey of prematurity as an individual, family, and community health problem. In Part I certain basic considerations are examined. These include criteria of prematurity; incidence (which has changed little in the past 30 years ); etiology and prevention (much more needs to be learned here!) with survival rates and with the most important question of the long-term influences of prematurity upon the subsequent growth and development and health of the child. In Part II Dr. Silverman deals with clinical matters and draws upon his own experience as director of the Premature Nursery at the Babies Hospital. In Section A the care of the premature from delivery until time of discharge from hospital is discussed in detail. Section B deals with the recognition and management of those abnormal conditions which occur most frequently in premature infants during the early months of life. Certain specific public health questions are considered in Part III. The utilization and interpretation of death certificate and hospital data and our current knowledge concerning the role of prematurity in the causation of neonatal mortality are reviewed. The development of city and state-wide programs for the care of prematures is described and several illustrative examples are given. The need for standards of care are emphasized and an organizational plan for a premature center is presented. An appendix deals in more detail with the use of statistical data and with standards and recommendations for hospital care. This is an extremely valuable and up-to-date text. DONALD C. SMITH

The role of the hospital consultation program in the prevention of prematurity and the death of prematures.

The role of the hospital consultation program in the prevention of prematurity and the death of prematures.

Acute renal insufficiency: Physiopathology and treatment, with presentation of cases occurring on an obstetric service

1.1. Maternal mortality rates are now so low that, for conservation of life, the fetus rather than the mother has become the primary concern of the obstetrician.2.2. More deaths occur in the first month of life than during all other periods in the pediatric age group up to 15 years.3.3. Of 150,000 fetal deaths each year, one-half are still births and one-half are neonatal deaths.4.4. Ninety per cent of this fetal loss is attributed to prenatal and natal causes.5.5. Pediatricians have requested and have been assigned the responsibility for the care of the newborn but they can function only as salvage officers whose results are limited by conditions already in effect.6.6. Infants under 1,500 grams comprise only 1.4 per cent of deliveries, but 36.9 per cent of fetal and neonatal deaths are in this group. Over half of these infants die within 24 hours of delivery. Since the combined mortality rate in this weight group is 78 per cent, the only prospective method for reduction of fetal loss is the prevention of prematurity.7.7. The infants who weigh between 1,500 and 2,500 grams comprise only 6.8 per cent of deliveries, but account for 29 per cent of the deaths. The combined stillbirth and neonatal mortality rate in this weight group has been reduced to 15 per cent and can probably be lowered further.8.8. Ninety-three per cent of deliveries are at term but they account for only 33.6 per cent of fetal deaths.9.9. Forty-seven per cent of stillbirths result from anoxia associated with premature separation of the placenta, placenta previa, or cord complications. An additional 10.4 per cent result from trauma. In 17.5 per cent stillbirth results from the fetal factors of congenital anomaly or erythroblastosis. In 16.8 per cent, the cause, other than prematurity alone, remains unknown.10.10. In contrast to stillbirths, only 10.5 per cent of neonatal deaths are directly due to anoxia. About 19.1 per cent are due to trauma, chiefly intracranial hemorrhage discovered at autopsy. The remainder of neonatal deaths are explainable by congenital anomalies (20.4 per cent), infection (5.9 per cent), erythroblastosis or maternal diabetes (10.5 per cent), hyaline atelectasis (14.5 per cent), and prematurity or unknown (19.1 per cent).11.11. In infants over 2,000 grams delivered by cesarean section the mortality rate is eight times that for those delivered by the vaginal route, and we are convinced that cesarean section should rarely be done in the primary interest of the fetus.12.12. Toxemia of pregnancy is related to fetal and neonatal mortality only to the degree that it increases the absolute number of premature deliveries.