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Interrelationships of circulating maternal steroid concentrations in third trimester pregnancies. II. C18 and C19 steroids: estradiol, estriol, dehydroepiandrosterone, dehydroepiandrosterone sulfate, delta 5-androstenediol, delta 4-androstenedione, testosterone, and dihydrotestosterone.

This report describes aggregate time trend effects of advancing gestational age on circulating maternal concentrations of 17beta-estradiol (E2), estriol (E3), dehydroepiandrosterone (D), dehydroepiandrosterone sulfate (D-S), delta 5-androstenediol (delta 5 diol), delta 4-androstenedione (delta 4 A), testosterone (T), and dihydrotestosterone (DHT) in a sequential series of 155 blood samples obtained from 19 normal pregnant women ranging from 26-40 weeks gestational age. Only E2, E3, and D-S show aggregate time trend effects. Log (E2) plots as a linear positive sloping curve from 26-40 weeks. Log (E3) plots as a positive sloping curve that is significantly steeper than log (E2) (P less than 0.05). Log (D-S) plots into a negative sloping curve which mirrors the pattern for log (E2) but cannot be statistically associated with log (E2) except for the opposite sign of their slopes, which are both significantly different from a zero slope (P less than 0.05). delta 4 A, T, DHT, delta 5 diol, and D show no aggregate time trends; however wide, comoving undulations for delta 4 A, T, DHT, and delta 5 diol between 26-28 and 38-40 weeks are confirmed in time by comparison of log mean plots and in magnitude by regressing the C19 steroids on one another. D shows virtually no association with the other C19 steroids. All C19 steroids, except for T, circulate at nonpregnant concentrations, implying that there is little placental secretion of these steroids into the maternal circulation.

Androgens

Interrelationships of circulating maternal steroid concentrations in third trimester pregnancies. III. Effect of intravenous cortisol infusion on maternal concentrations of estriol, 16 alpha-hydroxyprogesterone, 17 alpha-hydroxyprogesterone, progesterone, 20 alpha-dihydroprogesterone, delta 5-pregnenolone, delta5-pregnenolone sulfate, dehydroepiandrosterone sulfate, and cortisol.

The effect of a large dose (1000 mg) of iv cortisol-hemisuccinate on circulating steroid concentrations in five women, 28--34 weeks, gestational age, is reported. Maternal concentrations of estriol, 16 alpha-hydroxyprogesterone, 17 alpha-hydroxyprogesterone, progesterone, 20 alpha-dihydroprogesterone, delta 5-pregnenolone, delta 5-pregnenolone sulfate, dehydroepiandrosterone sulfate, and cortisol were measured by RIA before and at 8 and 12 h after iv cortisol infusions at 0 and 8 h. Data were evaluated by repeated measure analysis of variance. Estriol and 17 alpha-hydroxyprogesterone suppressed initially (P less than 0.05) and suppressed further with retreatment and increased treatment time (P less than 0.05). Dehydroepiandrosterone sulfate and progesterone suppressed initially (P less than 0.05) but did not suppress further with retreatment and increased treatment time (P greater than 0.05). delta 5-Pregnenolone and delta5-pregnenolone sulfate increased initially (P less than 0.05) but did not increase further (P greater than 0.05). Concentrations of 16 alpha-hydroxyprogesterone and 20 alpha-dihydroprogesterone were unchanged by cortisol infusion initially (P greater than 0.1) and with retreatment and increased treatment time (P greater than 0.1).

20-alpha-Dihydroprogesterone

Ultrastructure of the chorionic villus of the human placenta of the second and third trimester pregnancy.

38 human placentae of the 14th week of normal gestation were studied ultrastructurally. The thickness of the syncytial layer of villi varied markedly, and the syncytial cytoplasm showed marked vacuolization, which increased in the course of pregnancy in association with intensification of processes of resorption and absorption and hormonal function of the syncytium. Toward the end of the 2nd and at the beginning of the 3rd trimester of pregnancy, hypertrophic cytotrophoblastic cells appeared, whose ultrastructural character indicated functional stimulation. This observation contradicts the widely held view that cytotrophoblastic cells undergo gradual reduction in the course of pregnancy.

Chorionic Villi

[Electrocardiography, stress and the third pregnancy trimester].

Twelve patients whose ages ranged between 19 and 36 years, were studied. The gestational ages were between the 35th and the 39th week of pregnancy. The exercise performed was the one proposed by Kemp and Ellested. The analysis of the records comprised the electrocardiographic changes described by Dr. Chavez in his so called "syndrome of circulatory changes during pregnancy". Not all the characteristics were found in our cases, although this could be explained by the differences in the gestational age. The most common findings were the ST changes. In nine of our cases, they were more marked and appeared immediately after exercise and this makes us think that it could be due to the double load on the cardiac overload, that the exercise effects upon the cardiac muscle due to pregnancy. We could also advocate sympathetic and parasympathethic mechanisms, since in the final tracing this changes not only disappeared but were in some cases smoller than in the control. Regarding the cardiac rate it was found that it did not increase as shown in Robinson's Table. Nevertheless in eight cases, final tracings did not return to control levels and we could imply an "excess of heart rate" which is thought by Sheffield as a warning sign of coronary insufficiency. We will learn more about this after these same patients have had their-follow up studies when they are not pregnant. A larger series of cases is needed in the different trimesters of pregnancy as well as their reevaluation after the hormonal effects of pregnancy are over to ases the significance of this changes as well as their prognostic meaning during labor or as a warning sign of future coronary pathology.

Adult

Studies on pregnancy-associated plasma protein A in the third trimester of pregnancy.

The plasma concentration of pregnancy-associated plasma protein A (PAPP-A) was measured in 34 women during the last 10 weeks of pregnancy. From 30 to 36 weeks the concentration of this protein increased steadily. Thereafter the concentration of PAPP-A rose more steeply, the highest amounts being found in early labour. The concentration of PAPP-A in peripheral venous blood and in the uterine vein was much the same. It was less in the retroplacental blood and a great deal less in the peritoneal fluid. The day-to-day variation was small; the coefficient of variation at 38 weeks was only 7.3 per cent. After delivery, the concentration of PAPP-A fell more slowly than other placental proteins and steroids, the average half-life being 51 hours. Although there is no doubt that PAPP-A is a product of the syncytiotrophoblast, our findings suggest that it is not simply secreted by the chorionic villi directly into the intervillous space but makes its way into the maternal circulation by a more circuitous route.

Ascitic Fluid

Studies with a pancreatic beta cell simulator in the third trimester of pregnancies complicated by diabetes.

To determine the potential of an artificial pancreatic beta cell simulator as a therapeutic and research tool we have used the device for short-term monitoring and control of blood glucose concentrations in five pregnant patients with juvenile-onset diabetes (White's Class C) and three pregnant patients with maturity-onset diabetes (Class B). One patient with brittle juvenile-onset diabetes had successful control before, during, and after cesarean section. The other seven patients were studied during the third trimester of pregnancy and at least four weeks before delivery. Blood glucose control with Biostator regulation was excellent (mean, 96 mg. per deciliter; range, 85 to 107). The insulin requirements needed to achieve optimal glucose control with the Biostator were highly variable (range, 20 to 157 U. per 24 hours) but very similar to those previously calculated to provide optimal control by conventional means. Insulin requirements were unrelated to plasma growth hormone, placental lactogen, or glucagon concentrations. The greatest degree of insulin resistance was seen in obese patients with endogenous insulin-secretory capacity. This study indicates that a pancreatic beta cell simulator can normalize glucose concentrations and rapidly estimate daily insulin requirements in pregnant diabetic patients. In addition, the data suggest that exogenous insulin may indirectly suppress endogenous insulin secretion and thus contribute to the "insulin resistance" of obese patients with maturity-onset diabetes.

Adult

Plasma oxytocin and oxytocinase levels in third trimester of pregnancy and at labour.

In women during the third trimester of normal pregnancy and at labour the level of oxytocin and progesterone in plasma were determined by means of radioimmunoassay and the activity of oxytocinase was measured spectrophotometrically. The plasma oxytocin levels measured from the 25th week of pregnancy showed a gradual increase with the peak values at the 39th and 40th week. At labour, the oxytocin values remain at the same level as these found at the end of pregnancy. The increase in oxytocin levels at contractions compared to its values found between contractions was not statistically significant. Oxytocinase levels showed also an ascending character until the 38th week of pregnancy. Later, a decrease was found which continued until the termination of pregnancy. At labour, there was a decrease in progesterone level in plasma which was about at the limit of significance.

Aminopeptidases

Circulating levels of pregnancy-specific beta1-glycoprotein and human placental lactogen in the third trimester of pregnancy: their relationship to parity, birth weight, and placental weight.

Circulating levels of pregnancy-specific beta1-glycoprotein (SP1) and human placental lactogen (HPL) were measured in 153 normal subjects during the third trimester of pregnancy. The levels of SP1 and HPL showed a skewed distribution and rose progressively to reach a plateau by the 36th week. The normal range was calculated by ranking the data and division into centiles as well as by logarithmic transformation of the values. A low but significant correlation was observed between SP1 and HPL levels, SP1 and birth weight. There was also a correlation between HPL levels and placental weight.

Birth Weight

Acute non-lymphocytic leukaemia in the third trimester of pregnancy.

A 28-year-old woman with acute myeloblastic leukaemia was effectively treated with cytosine arabinoside and 6-thioguanine during the third trimester of pregnancy and a complete remission achieved. A normal infant was delivered at term. The patient survived for 27 months and the baby is now 2 1/2 years old with normal physical and mental development. The literature on management of acute non-lymphocytic leukaemia during the second and third trimester of pregnancy is reviewed and it is concluded that effective combination chemotherapy improves fetal survival.

Adult

Dietary intake in the third trimester of pregnancy and birth weight of offspring among nonprivileged and priviledged women.

The dietary intake during the third trimester of pregnancy among 20 nonprivileged and 10 privileged primigravidae in Addis Ababa was studied in a 2 day weighting inventory survey. With the exception of iron and thiamin, the nonprivileged group consumed a diet that was deficient in all nutrients, with an average daily protein and energy intake below 60% of the FAO/WHO Recommendations. The privileged group was found to meet the recommendations for all nutrients except for calcium and riboflavin. Infants born to the nonprivileged women had significantly lower mean birth weight when compared with the infants born to the privileged women.

Adolescent

Primary hyperparathyroidism during the third trimester of pregnancy.

Primary hyperparathyroidism during pregnancy has been reported in 36 women; 1 new case is reported here. Screening by determining serum calcium levels is a valuable method of diagnosing the disease. Radioimmunoassay of serum parathyroid hormone (PTH) greatly aids in the diagnosis. Amniotic fluid PTH values are discussed. Hyperparathyroidism has a high association with progressive renal insufficiency, renal calculi, hypertension, and bone disease. During pregnancy, there is an increased incidence of stillborns, premature labor, and neonatal tetany. Acute hyperparathyroid crisis may result in maternal death. This is the first reported case surgically treated during the third trimester of pregnancy. Surgery should be considered when the diagnosis is made late in pregnancy, as this may protect the infant from neonatal tetany.

Acute Disease

A double-blind investigation into the effects of ritodrine on uterine blood flow during the third trimester of pregnancy.

The object of this double-blind crossover study was to investigate the effect of a beta-mimetic agent-ritodrine-administered intravenously at increasing infusion rates on uterine blood flow and the maternal cardiovascular system during the third trimester of normal pregnancies and pregnancies complicated by intrauterine growth retardation and/or hypertension. Uterine blood flow, maternal arterial blood pressure, maternal and fetal heart rate, and uterine activity were simultaneously recorded throughout the study. In normal pregnancies the changes in different parameters during ritodrine and placebo administration were slight. In the "pathologic" pregnancies there was a highly significant increase in maternal heart rate, differential blood pressure, and uterine blood flow during ritodrine administration. The differences in response to ritodrine and placebo were statistically significant in this later group. This study demonstrates increased sensitivity of the maternal cardiovascular system to this beta-mimetic agent in certain categories of high-risk pregnancies and possibily an increase in uteroplacental blood flow.

Blood Pressure

Fetal movements in human pregnancies in the third trimester.

Fetal movements (FM) were measured using a real-time B-scan method in 50 women in the third trimester. One hundred ninety-five observations were made. The number of FM per 20-minute observation period was similar in normal, diabetic, and hypertensive pregnancies and in patients with placenta previa, but was significantly lower in patients with Rh isoimmunization and an affected fetus. The number of FM did not vary with gestational age, mode of delivery, or birth weight and was significantly increased in patients either with a reactive nonstress test (NST) or in the presence of fetal breathing movements (FBM). Fetal movements were absent before delivery in 4 patients: In 3, the fetus died in utero and in the other a positive contraction stress test (CST) was observed. Conversely, in 2 other fetuses who died in utero, FM were observed during the last examination before death. In both, the cause of fetal death was related to an acute change. No relationship between FM and neonatal death was observed. These data suggest FM monitoring may be helpful in evaluating antepartum fetal condition.

Antibody Formation