Epidemiologic aspects of shoulder dystocia-related neurological birth injuries.

PURPOSE: The first part of the study involved data collection for the detection of geographic variations and chronologic fluctuations in the rates of shoulder dystocia. The second part of the research evaluated head-to-body delivery times in cases of arrest of the shoulders at birth that had resulted in fetal damage during the last four decades in the USA. METHODS: The study of geographic and chronologic changes in the rates of shoulder dystocia rested on reported statistics coming from the USA and 11 other countries. These data were obtained by computer search. Evaluation of head-to-body delivery times rested on 104 well-documented cases that resulted in permanent neonatal damage. RESULTS: Literary reports of shoulder dystocia indicate that the incidence of shoulder dystocia has increased in the USA about fourfold since the middle of the twentieth century. No comparable trend has been reported from most other countries. Study of head-to-body delivery times revealed that more than two-thirds of all injured fetuses had been extracted from the birth canal within 2 minutes. CONCLUSIONS: Incidents of shoulder dystocia began to escalate in the USA during the 1980s, shortly after the introduction of "active management" of the birthing process. This new technique replaced a conservative philosophy which had recommended abstinence from intervention on the part of the accoucheur. The authors consider the interventionist approach largely responsible for the exponential increase in the rates of shoulder dystocia in the USA. They recommend adherence to the traditional method of delivery on the part of obstetricians in Europe and elsewhere.

Shoulder dystocia related fetal neurological injuries: the predisposing roles of forceps and ventouse extractions.

On the basis of 333 documented cases of permanent perinatal neurological damage, associated with arrest of the shoulders at birth, the authors conducted a retrospective study in order to evaluate the predisposing role, if any, of the utilization of extraction instruments. The investigation revealed that 35% of all injuries occurred in neonates delivered by forceps, ventouse or sequential ventouse-forceps procedures. This frequency was several-fold higher than the prevailing instrument use in the practices of American obstetricians during the same years. A high rate of forceps and ventouse extractions was demonstrable in all birth weight categories. Average weight and moderately large for gestational age fetuses underwent instrumental extractions more often than grossly macrosomic ones. This circumstance indicates that forceps and ventouse are independent risk factors, unrelated to fetal size. Their use entailed central nervous system injuries significantly more often than did spontaneous deliveries. The findings suggest that extraction procedures may be as important as macrosomia among the factors that lead to neurological damage in the child in connection with shoulder dystocia. Because they augment the intrinsic dangers of excessive fetal size exponentially, the authors consider their use in case of > or =4,000 g estimated fetal weight inadvisable. Sequential forceps-ventouse utilization further doubles the risks and is, therefore, to be avoided in all circumstances.

Incidents of catastrophic overhydration (maternal and neonatal) identified through medico-legal reviews.

The authors describe two incidents where a mother postpartum and a neonate in the nursery were grossly overhydrated in tertiary care medical centers. In the first case, while receiving intensive care for HELLP (hemolysis, elevated liver enzymes and low platelets) syndrome, involving the participation of eight specialists and subspecialists, the weight of the mother increased by 54% between the 2nd and 8th postpartum days. In the second case, between the time of his birth and his demise 13 days later, the weight of the newborn child increased by 67%. In neither of these cases, was the significance of grossly excessive hydration recognized as a problem either during the management or in retrospect. Only the subsequent medico-legal reviews drew attention to the fact that, in both instances, the participating consultants had ordered the infusion of large quantities of fluids independently of one another without making an attempt to coordinate their activities. The resident and nursing personnel uncritically implemented all of their instructions.

The risk of shoulder dystocia related permanent fetal injury in relation to birth weight.

OBJECTIVE: To examine birth weight related risks of fetal injury in connection with shoulder dystocia. STUDY DESIGN: The investigation was based on a retrospective analysis of 316 fetal neurological injuries associated with deliveries complicated by arrest of the shoulders that occurred across the United States. RESULTS: The study revealed that the distribution of birthweights for the high risk shoulder dystocia population differs from the standard birthweight distribution. The relative difference per birthweight interval is used to adjust an assumed 1:1000 baseline risk of injury due to shoulder dystocia following vaginal deliveries. These adjusted risks show a need to consider new thresholds for elective cesarean delivery. CONCLUSIONS: Current North American and British guidelines, that set 5000 g as minimum estimated fetal weight limit for elective cesarean section in non-diabetic and 4500 g for diabetic gravidas, may expose some macrosomic fetuses to a high risk of permanent neurological damage. The authors present the opinion that the mother, having been informed of the risks of vaginal versus abdominal delivery, should be allowed to play an active role in the critical management decisions.

Preterm premature rupture of membranes in pregnancies complicated by human immunodeficiency virus infection: a single center's five-year experience.

OBJECTIVE: The objective of this study was to describe one center's five-year experience of the management of human immunodeficiency virus (HIV) positive gravidas with preterm premature rupture of the membranes (PPROM) not in labor at

Erb's palsy after delivery by Cesarean section. (A medico-legal key to a vexing problem.).

Despite impressive progress in perinatology, fetal injuries from arrest of the shoulders at birth have not decreased in recent decades. Based upon sporadic reports of Erb's palsy in neonates born by Cesarean section, some obstetricians embraced the theory recently that brachial plexus lesions often derive from spontaneous forces acting in utero. Having reviewed three hundred malpractice claims involving fetal injuries attributed to shoulder dystocia at birth, the authors found only two cases connected with abdominal deliveries. One followed manual replacement of the already delivered fetal head into the pelvis after sequential vacuum and forceps procedures and failed manual extraction of the body. The other was an elective repeat Cesarean section where extensive adhesions limited the available space for the lower segment transverse uterine incision. Coincidental fracture of the clavicle and absence of contractures or deformities indicated that the brachial plexus injury was acute, having resulted from forceful traction at delivery.

Diabetes, hypertension and birth injuries: a complex interrelationship.

Seemingly coincidental occurrence of various pathological conditions may derive from common etiologic denominators. While reviewing 240 malpractice claims involving shoulder dystocia related fetal injuries, we found two antenatal complications in the background conspicuously often. Chronic or pregnancy induced hypertension was identifiable in 80 instances (33%). Pregnancy induced or preexisting diabetes was diagnosed 48 times (20%). Many of these patients were poorly controlled. The blood pressure was usually checked during the antenatal visits. However, about one-half of all patients received no diabetic screening. Therefore, this study may underestimate the actual incidence of diabetes. It has been calculated that the frequency of diabetes in pregnancy and that of hypertension, is about 5% in the United States. Thus, the rates of these complications in this selected group of gravidas was severalfold higher than in the general population. Since hypertension causes retarded fetal growth, it cannot be a direct cause of arrest of the shoulders at delivery. The likely common denominator is maternal diabetes a known predisposing factor both for preeclampsia and shoulder dystocia at birth. In the course of litigations for fetal injuries, demonstration of the predisposing role of seemingly unrelated shortcomings of the medical management may profoundly influence the outcome. This principle is demonstrated by the presentation of an actual malpractice action which resulted in a substantial settlement.

Varicella vaccination during early pregnancy: a cause of in utero miliary fetal tissue calcifications and hydrops?

BACKGROUND: It is the purpose of this article to describe a suspected association of inadvertent vaccination with varicella vaccine during early pregnancy with the subsequent development of in utero miliary fetal tissue calcifications and fetal hydrops detected by sonogram at 15 weeks of gestation. CASE: This is a case presentation of a pregnant patient who received varicella vaccination during the same menstrual cycle that she became pregnant, and is supplemented by a literary review. The fetus developed miliary fetal tissue calcifications and fetal hydrops detected by a targeted sonogram at 15 weeks gestation. CONCLUSION: Varicella vaccination during early pregnancy may be a cause of miliary fetal tissue calcifications and fetal hydrops.