Emanuel A. Friedman

The graphic analysis of labor

Abstract 1. The efficacy of plotting cervical dilatation against time as a method of graphically analyzing labor is demonstrated. 2. The sigmoid characteristics of the curves thus obtained in primiparas at term are illustrated. 3. The first stage of labor is divided into four phases based on the graphic alterations noted. Their respective limits are defined. 4. Primary and secondary inertia are redefined in terms of deviation from the “normal.” 5. The application of this method to the study of the effects of sedation, stimulation, anesthesia, etc., upon the course of labor is indicated. 6. The value of this method for the study of individual labors, in progress, is stressed.

Aortic lymph node metastases in early ovarian cancer

Abstract Aortic node biopsies performed in 26 patients with Stage I ovarian cancer revealed 5 with metastases. All were associated with virulent tumors of the undifferentiated anaplastic or embryonal cell type. The 19 per cent incidence of lymphatic metastasis in this area stresses the need for evaluation of the aortic node chain in patients with early delimited ovarian cancer.

Effect of Fetal Monitoring on Neonatal Death Rates

We analyzed data from 15,846 live-born infants to assess the effect of electronic fetal monitoring on neonatal death rates. The crude neonatal death rate was 1.7 times higher in unmonitored infants than in those monitored. Adjusting for inherent risk and changes in mortality rates and monitoring rates during the years of the study lowered the relative risk to 1.4 (95 per cent confidence interval, 0.85 to 2.45). The estimated yield from monitoring decreased as the inherent risk of the baby declined. Thus, in the highest-risk group 109 lives might be saved for every thousand babies monitored. In the lowest risk group (babies at term with no risk factors) the neonatal death rate is around one per thousand. The absolute benefit for this large group could therefore not exceed one life saved for every thousand babies monitored.

Causes of perinatal death associated with gestational hypertension and proteinuria

Abstract This study determined the frequency of the individual placental and fetal disorders responsible for the excessive perinatal mortality rate associated with gestational hypertension and proteinuria. In a large prospective study of pregnancy 3.2 per cent of the mothers were classified as hypertensive when one or more measurements of gestational diastolic blood pressure were 85 mm. Hg or more and proteinuria was 1+ or greater. The perinatal mortality rate for these pregnancies was 37.9 per 1,000 births compared with 17.2 per 1,000 for normotensive gestations without proteinuria. Forty-two per cent of the total excess perinatal mortality rate in the pregnancies complicated by hypertension was due to large placental infarcts, 15 per cent to placental growth retardation, and 13 per cent to abruptio placentae. Both the frequency of occurrence and perinatal mortality rate increased for each of these disorders with increasing maternal blood pressures.

Risk factors for shoulder dystocia in the average-weight infant

Almost half (47.6%) of all deliveries with shoulder dystocia occurred in association with the delivery of an average-weight infant (under 4000 g). Of 4294 nondiabetic gravidas delivering infants of birth weight 3500 to 3999 g, 94 (2.2%) experienced a shoulder dystocia. Protraction and arrest disorders were associated with a statistically significant increase in the incidence of shoulder dystocia, and this effect was further augmented by low forceps delivery. Among 6252 infants weighing 3000 to 3499 g, there were 40 instances of shoulder dystocia (0.6%). Only arrest disorders were associated with an increased rate.

Cervimetry: An objective method for the study of cervical dilatation in labor

Abstract 1. 1. A mechanical device for the objective study of cervical dilatation in labor has been described. Its design and method of application have been detailed. 2. 2. Material is presented describing the findings obtained through the use of the cervimeter in a group of 25 primigravid patients. 3. 3. The sigmoid nature of the normal cervical dilatation-time curve in the primigravida is definitively demonstrated. 4. 4. The potentialities of the instrument are outlined.

Perils of the new labor management guidelines.

Recent guidelines issued jointly by the American College of Obstetricians and Gynecologists and the Society for Maternal-Fetal Medicine for assessing labor progress differ substantially from those described initially by Friedman, which have guided clinical practice for decades. The guidelines are based on results obtained from new and untested methods of analyzing patterns of cervical dilatation and fetal descent. Before these new guidelines are adopted into clinical practice, the results obtained by these unconventional analytic approaches should be validated and shown to be superior, or at least equivalent, to currently accepted standards. The new guidelines indicate the patterns of labor originally described by Friedman are incorrect and, further, are inapplicable to modern obstetric practice. We contend that the original descriptions of normal and abnormal labor progress, which were based on direct clinical observations, accurately describe progress in dilatation and descent, and that the differences reported more recently are likely attributable to patient selection and the potential inaccuracy of very high-order polynomial curve-fitting methods. The clinical evaluation of labor is a process of serially estimating the likelihood of a safe vaginal delivery. Because many factors contribute to that likelihood, such as cranial molding, head position and attitude, and the bony architecture and capacity of the pelvis, graphic labor patterns should never be used in isolation. The new guidelines are based heavily on unvalidated notions of labor progress and ignore clinical parameters that should remain cornerstones of intrapartum decision-making.

COMPUTER ANALYSIS OF LABOUR PROGRESSION

THE relationship between cervical dilatation and duration of labour can be expressed as a sigmoid curve with empirical formula y = a+ abc’, of a type first described by Gompertz in 1825 (Davis, 1943), but solution of this equation and calculation of the four constants of each curve is intricate and tedious, making practical utilization unlikely. In 1963 we developed a computer programme that was capable of verifying the mean formula for nulliparae, y = 2*30+7.70 (0.016)0.34x, but it was found to be time consuming (in terms of machine time) and the data derived from its use had little practical value. The solution of the Gompertz equation constants by computer techniques was available and could be applied to homogeneous samples for study of factors that might influence the course of labour, but this only provided a mean hypothetical curve for any given set of data. Correlation or statistical comparisons between groups were considered to be beyond our capabilities at the time. Search for reduction in mathematical complexity included attempts at transformation of the data to linearity by using the method of probit analysis developed by Bliss (Bliss, 1934; Finney, 1952). The effect of this form of transformation from absolute values to probits is to convert the normal sigmoid curve to a straight line. The value of this mathematical device was limited in our case by the asymmetry of the cervical dilatation-time function curves and by diminishing accuracy of the system at the extremes. Largely by trial and error a working solution to the problem of machine “case finding” and analysis has been developed by which the computer can be programmed to accept clinical estimations of cervical dilatation and duration of elapsed time in labour, to decide whether the data are acceptable, and then define critical durations and slopes, construct curves, and diagnose abnormalities in the individual patient. For homogeneous groups of patients, the computer can define means and distributions so as to provide data for establishing limits, determining regressions, correlations and comparisons.

Dysfunctional labor XII. Long-term effects on infant.

Developmental studies were done at 3 and 4 years of age in a series of 656 children and the results were correlated with the preceding labor pattern and the type of delivery. It was determined that there were significant adverse effects among offspring delivered by midforceps procedures or born following labors characterized by prolonged deceleration, secondary arrest of dilatation, or arrest of descent.

Fetal morbidity following potentially anoxigenic obstetric conditions: I. Abrupito placentae☆☆☆

Abstract 1. 1. The incidence of abruptio placentae among 17,265 parturients and its relationship to race, parity, maternal age, duration of pregnancy, and toxemia are presented. 2. 2. The correlations with prematurity and with toxemia of pregnancy are reconfirmed. 3. 3. The perinatal mortality associated with this disorder and the neurologic status of the infants who survive is evaluated. The risks inherent in this potentially anoxigenic condition and the chances for the surviving infant to be neurologically intact are discussed.