L.A. Calkins

The etiology of occiput presentations

Summary If presentation in the right oblique diameter occurs with mach greater frequency than in the left oblique, as is generally agreed by most writers (about seven to one) and has occurred roughly three to one in this series, it would seem that some more adequate explanation than the presence of the pelvic colon in the left, posterior quadrant of the pelvis must be offered. The presence of the urinary bladder in the right anterior quadrant convincingly offers this additional explanation and, in fact, the bladder would seem to be a more important factor than the pelvic colon. It may also be noted that the total of occipitoposterior presentations (981) approximates the total of oecipitoanterior presentations (1,021). Possibly, therefore, occiput posterior is not such a serious complication as we have been urged to believe. We hope to discuss this subject soon.

An Analytical Determination of its Clinical Importance

Summary There is apparently a very close relationship between both height and weight of the baby and placental size. The next closest relationship exists between duration of pregnancy and placental size. This relationship, however, is less than that between the size of the baby and the size of the placenta, and in this same series of cases there is a much closer relationship between duration of pregnancy and size of the baby (+0.430 ±0.021) than there is between duration of pregnancy and size of the placenta. The evident conclusion is that whereas the placenta continues to grow in the latter part of pregnancy, it does so at a relatively much less rapid rate than the baby. The apparent (low degree of) correlation between blood loss in the third stage of labor and placental size is again perhaps more apparent than real, as the correlation between blood loss and infant size in this series shows a coefficient (+0.216 ±0.016) somewhat larger than that between size of placenta and blood loss. It would seem then that the larger placentas are associated with greater blood loss only because they are also associated with larger babies. Perhaps the greater distention of the uterus associated with the larger babies is a more important factor in the production of blood loss than the larger placental area of attachment. Indeed, one might doubt whether a large placental site produces any greater blood loss than a small placental site. Physiologically there should be no difference. Comparison of the data on placental weight with those on placental area would indicate that the latter is less important than the former, because the coefficients of correlation in every instance (where a definite coefficient was present) were less than the coefficients for placental weight. It would seem then that the determination of placental weight alone would be quite sufficient for clinical purposes and that the addition of placental dimensions adds little, if anything, to the value of our clinical charts.

Occiput posterior: Incidence, significance, and management

Abstract Occiput posterior and occiput anterior occurred with about equal frequency in this series of 2,130 cases, where more than the usual care was taken to arrive at an early and accurate diagnosis. Occiput posterior was characterized by a somewhat longer first stage of labor. The difference, however, is not over one to one and one-half hours and the first stage in occiput right posterior is probably not much, if any, longer than in occiput anterior. The difference in the second stage is a matter of a few minutes only. Operative delivery, particularly low forceps, is more frequent in occiput left posterior than in the other three positions by about three cases in each one hundred. Fetal mortality is no greater in occiput posterior than in occiput anterior under the plan of management employed for this series. It should be noted that no pituitary extract was given previous to the delivery of the placenta and anesthesia was confined to nitrous oxide plus morphine on indication. Maternal morbidity was about 3 per cent greater for occiput left posterior than for the other three positions. Spontaneous internal rotation occurred in about 94 per cent of occiput posterior as compared with not over 96 per cent of occiput anterior. Inasmuch as nearly half of the unrotated babies were delivered spontaneously without injury to the mother and without a single fetal death, the problem of failure of spontaneous internal rotation would seem to be not greater than 3 per cent for occiput anterior and 3.5 per cent for occiput posterior. Our present attitude toward occiput posterior is identical to our attitude toward occiput anterior, except that we realize that patience to the extent of about one hour more of waiting is required. Williams 4 has, previously, expressed a similar attitude.

Labor in the American Negro.

Abstract Careful analysis of consecutive labors of 4,103 white patients and 6,041 Negro patients reveals some interesting points: 1. 1. Of all the major complications of pregnancy, only the late toxemias are more frequent in the Negro race, 5.2 per cent versus 3.1 per cent. 2. 2. Premature labor (infants under 2,500 grams) is more frequent in the Negro race (10.1 per cent contrasted with 6.4 per cent) but caused only a slightly greater loss of all babies (1.05 per cent contrasted with 0.95 per cent) because of the consistently lower mortality rate of the Negro infants in each premature weight group from 1,000 to 2,495 grams. 3. 3. The first stage of labor is consistently longer in the Negro patients. In primigravidas this difference approximates 2 hours and is something less than one hour in multigravidas. 4. 4. The second stage of labor, both descent and pelvic floor phases, is definitely shorter in the Negro patient. These differences are small. 5. 5. Blood loss in the third stage is markedly less. Blood loss of 500 c.c. or more occurred in about 6 per cent of the white patients. and in only 2 per cent of the Negro patients. 6. 6. Fetal perinatal mortality is higher (1.98 in contrast to 1.58 per cent) among Negroes. 7. 7. Maternal morbidity is some 30 per cent higher in Negro patients.