H. Frank Andersen

Gestational age assessment. I. analysis of individual clinical observations.

Accurate assessment of the estimated date of confinement is a cornerstone of obstetric care. Traditionally this date has been predicted from historical and clinical examinations; however, there have been few studies of the accuracy of such predictions. Multiple estimators of gestational age were examined in 418 patients who were delivered of infants weighting larger than or equal to 3,000 gm, following spontaneous onset of labor. Mean intervals from an event to delivery were calculated for last menstrual period (284.2 days), quickening (156.3 days), first audible fetal heart tones (136.2 days), uterine fundus at the umbilicus (140.8 days), and measurements of the fundal height. The variability in each of these estimators was examined and compared. The last menstrual period, if known with certainty, is the most accurate estimator, followed by the uterus at the umbilicus, first heard fetal heart tones, fundal height, and quickening.

Gestational age assessment: II. Prediction from combined clinical observations

Accurate assessment of the estimated date of confinement is a cornerstone of obstetric care. In an earlier report, we examined the time of occurrence of various historical and clinical estimators of gestational age in relation to the date of delivery. We now examine the possibility of combining multiple clinical estimators to improve the prediction of delivery date. Formulas for predicting delivery date from multiple clinical estimators were developed in a group of 418 patients who were delivered of infants weighing greater than or equal to 3,000 gm, after spontaneous onset of labor. These formulas were tested in a separate group of 107 patients who fulfilled similar criteria. In patients with a known last menstrual period, additional clinical information did not improve the prediction of delivery date; however, if the last menstrual period was uncertain or unknown, averaging the predicted delivery dates by several clinical examinations provided a prediction of delivery date as precise as if the last menstrual period were known.

Outpatient sedation: An essential addition to gynecologic care for persons with mental retardation

Routine gynecologic care for persons with mental retardation may be difficult to provide, especially to those women who do not allow a pelvic examination to be performed. Of 275 women referred to a multidisciplinary clinic addressing the reproductive health concerns of mentally retarded women, 61 patients (22%) did not allow a gynecologic examination to be performed. The administration of ketamine alone, midazolam alone, or a combination of midazolam and ketamine allowed for the successful performance of a gynecologic examination in 81% of previously uncooperative women. No adverse effects of the medications were noted. We conclude that sedation of difficult-to-examine, mentally handicapped women can be safely performed in the outpatient setting, thus avoiding the need for general anesthesia and its inherent risks.

Why the heart is like an orchestra and the uterus is like a soccer crowd

TO THE EDITORS: Thank you for your interesting commentary on the mechanism of uterine activity leading to organized labor. Your analogy of the soccer stadium (or perhaps football in an American context) for uterine contractility in labor as compared with the organized sequence of cardiac contractility is very apt. It is almost certainly true that organized uterine contractions (labor) are possible only because of the ability of electrical activity to propagate through gap junctions. Drs Mel Barclay, Carl Simon, and I investigated a computer model of uterine activity based on the concept of propagation via gap junctions. The model demonstrated organized propagation of contractile activity when adequate connections were available between the cells of the computer model. Dr Barclay and I had many conversations about the presence or absence of a pace-making function in the uterus. He believed that the anatomic studies of Toth and Toth demonstrated a pacemaker region, whereas I am skeptical. The computer model, admittedly simple, that we developed required a pacemaker function for prolonged contractile activity; however, we found some evidence that more accurate modeling of electrical characteristics of the cells would generate self-sustaining patterns. I suspect that regions of the myometrium with higher rates of contractility eventually take over the coordination of contraction patterns. Unfortunately, our studies did not continue after Dr Barclay’s death in 2010. I continue to believe that further modeling of the uterus as a construction of cellular automata with connections governed by physiological and electrochemical processes that you summarize will advance our understanding of both organized and disorganized (dysfunctional) labor. -

ESTAGEST: an obstetrical application program in BASIC for the computation of estimated date of confinement.

The establishment of the estimated date of confinement (EDC) is an essential element in the care of pregnant women. Unfortunately, accurate information on the last menstrual period, the usual determinant of EDC, is not always available, or clinical estimations of gestational age may be discrepant. Prior studies have demonstrated that an average of several clinical examinations can provide a useful prediction of EDC. We have developed a simple BASIC computer program which allows the clinician to input up to 20 clinical examinations and determines the average EDC based on the clinical dates. The program displays the EDC for each individual examination, which provides an indication of the dispersion, or discrepancy, among the examinations. Average intervals to delivery date from the occurrence of clinical estimators of gestation are based on observed data at our institution and can be easily modified to fit local norms.