Fetal insulin and growth hormone metabolism in the subhuman primate.

The concentrations of plasma glucose, insulin, growth hormone, and immunoreactive growth hormone-like substance in subhuman primate fetal and maternal plasma were examined after the intravascular administration of glucose, arginine, or tolbutamide to the fetus. Cannulation of interplacental vessels permitted studies on the fetus in utero without disruption of fetal-placental-maternal anatomic integrity. Single glucose injections, glucose infusions, and arginine infusions into the fetus did not alter fetal plasma insulin concentrations. In contrast, tolbutamide injections elicited an immediate 3-4-fold increase in fetal plasma insulin concentrations. A bidirectional placental transfer of insulin was demonstrated with the use of simultaneously injected insulin-(125)I to the mother and insulin-(131)I to the fetus. Simian fetal plasma contained a substance which cross-reacted with immunologic identity to human growth hormone. In contrast, simian maternal plasma and amniotic fluid reacted with immunologic nonidentity to human growth hormone. Although glucose administration to the fetus did not suppress nor did arginine infusion consistently augment fetal plasma growth hormone levels, the latter were observed to vary in individual experiments. The plasma responses to the same stimuli in the neonate were also examined. In contrast to the fetal experiments, glucose injection in the neonate elicited a delayed rise in the concentration of plasma insulin. Similar to the fetus, the plasma concentration of insulin increased after tolbutamide injection and did not change in response to arginine infusion. The initial concentrations of neonatal plasma growth hormone were significantly lower when contrasted with the initial fetal plasma levels. There was no difference in the responsiveness of the fetal and neonatal growth hormone-releasing mechanisms when challenged by glucose or arginine infusion. The data indicate that the fetal plasma concentration of growth hormone is labile, that fetal growth hormone metabolism may differ from that in the neonate, and that pancreatic islet cell responsiveness rapidly changes after delivery.

Factors affecting the response to insulin in the normal subhuman pregnant primate.

The concentrations of plasma glucose, free fatty acids, insulin, growth hormone, and placental prolactin in subhuman primate fetal and maternal plasma were examined following intravascular administration of insulin and glucagon to the fetus and mother. The neonatal plasma responses to these same stimuli were also examined. Fetal plasma glucose concentrations were minimally altered by direct fetal insulin injections, whereas neonatal glucose levels declined with similar injections. In both instances, however, plasma free fatty acid levels declined following insulin. When the amount of insulin given the fetus was increased, fetal plasma glucose concentrations did decline. Combined intravascular insulin injections and infusions in the mother were associated with a disappearance of the initial maternal to fetal plasma glucose concentration gradient and a nearly parallel fall in both maternal and fetal plasma glucose levels. It was concluded that insulin was biologically active in the fetus. Obtunded fetal plasma glucose responses to direct fetal insulin administration may be a function of placental transfer of glucose from the maternal pool. Maternal plasma placental prolactin and fetal plasma growth hormone levels were unchanged in the presence of sustained maternal and fetal hypoglycemia. However, neonatal plasma growht hormone levels did increase in response to hypoglycemia. The observed bidirectional placental barrier to transfer of radioisotopically labeled growth hormone indicated that fetal plasma growth hormone was solely of fetal origin. These data suggested further that a change in the growth hormone-releasing mechanism may occur from fetal to neonatal life. Direct maternal intravascular glucagon administration led to augmentation in both maternal and fetal plasma insulin and glucose levels. Direct fetal glucagon injections enhanced both maternal and fetal plasma insulin levels. These simultaneous changes in both plasma pools were consistent with the demonstration of a bidirectional placental transfer of radioisotopically labeled glucagon. The role of endogenously produced glucagon in these studies remains to be clarified.

Osteogenesis imperfecta as a complication of pregnancy.

Osteogenesis imperfecta is a complex disorder that rarely complicates pregancy. The successful obstetric management of a patient with severe osteogensis imperfecta is presented along with a detailed review of maternal osteogenesis imperfecta in the recent English literature. A review of the disease process, its complications, and associated disorders is presented.

Ultrasound and the prenatal diagnosis of congenital anomalies: a medicolegal perspective.

A survey was conducted to determine the frequency of obstetric ultrasonography use, its value in detecting fetal anomalies, and the frequency with which ultrasound errors lead to malpractice allegations. Questionnaires were sent to one-fifth of The American College of Obstetricians and Gynecologists Fellows in District IV and were returned by 68%. Ultrasound equipment is housed in the offices of nearly 64% of the responding obstetricians, and ultrasound scanning is used in 69% of pregnancies in the district. Over 67% of obstetricians have detected one or more fetal anomalies by ultrasonography, and over 51% have overlooked anomalies. Ultrasound-related lawsuits were reported by 4.7% of the respondents.

Pregnancy in women over forty.

In a retrospective review of 440 pregnancies occurring in women over the age of 40, increased frequencies of both perinatal and maternal complications were noted. The perinatal mortality rate of the study group was three times greater than that of the general obstetric population. There were increased incidences of both low and high birthweight infants. Neonatal morbidity was increased. Congenital abnormalities were noted in 12 infants, including 2 infants with cytogenetic abnormalities. Hypertensive disorders complicated one-third of the pregnancies. Diabetes mellitus and abruptio placentae occurred with increased frequency. Cesarean section was required in 12.2% of the deliveries.

Comparative study of stressed and nonstressed antepartum fetal heart rate testing.

During an 18-month period 1328 nonstress tests (NST) and sequential contraction stress tests (CST) were performed on 566 patients. The criterion for reactivity was at least 2 accelerations associated with fetal movement during 20 minutes. The last test performed within 1 week of delivery was compared with perinatal outcome. A total of 1118 (84.2%) NSTs were reactive, and 210 (15.8%) were nonreactive. Of the CSTs 1249 (94.1%) were negative, 52 (3.9%) were positive, 16 (1.2%) were equivocal, and 11 (0.8%) were unsatisfactory. The correlation between a reactive NST and a negative CST was excellent (99.4%), whereas that between a nonreactive NST and a positive CST was poor (24.8%). Although the CST proved to be a better predictor of morbidity than the NST, both tests are highly significant predictors (P less than .001). Fetuses exhibiting both a nonreactive NST and a negative sequential CST are at no increased risk for morbidity. This study supports the concept that a precisely defined NST is an adequate screening tool for the evaluation of high-risk pregnancies.

Relation of large birthweight to maternal diabetes mellitus.

The records of 517 pregnancies which terminated in the delivery of infants weighing 9 lb or more were reviewed. The obstetric patient most likely to deliver a large birthweight infant was characterized. Toxemia, prolonged labor, and puerperal morbidity occurred with increased frequency. Many of the deliveries were complicated by fetopelvic disproportion with resultant increase in mid-forceps deliveries, cesarean sections, and perinatal morbidity. Five of the 517 patients delivering large birthweight infants were known to have diabetes mellitus prior to the pregnancy included in this study. An additional 369 patients were evaluated with intravenous glucose tolerance tests. Thirty-eight (10.3%) of the 369 tested proved to have diabetic glucose tolerance curves. The likelihood of finding maternal diabetes mellitus increased with the infant's birthweight. Multiple regression analysis of other clinical variables failed to predict which patients would prove to have diabetes. Identification of diabetic puerperas requires that glucose tolerance tests be performed in all who delivered large birthweight infants.

Failure of triiodothyronine to prevent propylthiouracil-induced hypothyroidism and goiter in fetal sheep.

Administration of propylthiouracil (PTU) to pregnant, third trimester sheep led to decreasing serum thyroxine and increasing serum thyroid-stimulating hormone in both mothers and fetuses. Hypothyroidism appeared more pronounced in the fetuses than in the ewes, and goiter formation was observed in all fetuses exposed to PTU. Concomitant administration of triiodothyronine failed to protect the fetuses from the effects of PTU.

Antepartum heart rate testing in diabetic pregnancy.

Fetal death in utero remains a significant contributor to diabetics' perinatal mortality despite the reassuring results of antepartum heart rate testing. We retrospectively reviewed 48 pregnancies (one set of twins) of class B-F diabetic women with a reactive nonstress test (NST) or a negative contraction stress test (CST) within one week of delivery. Four fetal deaths occurred four to seven days after the test; no fetal deaths occurred within three days of it. We advocate initial screening with the NST, followed by a CST if the NST is nonreactive. Testing should be done more often than weekly.

Schistocytosis, aminotransferase elevation and thrombocytopenia in preeclampsia/eclampsia.

Some preeclamptic patients have schistocytosis, abnormal liver function tests and thrombocytopenia. To determine how strongly these three abnormalities cluster with each other, a sequential series of 49 preeclamptic or eclamptic patients was analyzed for the presence of schistocytosis, serum aminotransferase elevation and thrombocytopenia. These three abnormalities were found less often together (the HELLP syndrome) than singly or in pairs. These data do not clearly separate HELLP patients from other preeclamptic patients.

A comparison of magnesium sulfate and terbutaline for the arrest of premature labor. A preliminary report.

Intravenous magnesium sulfate and terbutaline were compared as treatments for premature labor. A successful treatment was the arrest of labor for 24 hours. Early treatment was essential for successful management of premature labor. In this study, magnesium sulfate and terbutaline were equally effective in controlling premature labor. Whereas terbutaline was associated with significant alterations in diastolic blood pressure, maternal pulse, fetal heart rate and potassium concentration, magnesium sulfate was not. Magnesium sulfate holds promise as a tocolytic agent, and further clinical study of it is warranted.

A counseling dilemma involving anencephaly, acrania and amniotic bands.

A suggested fetal anencephaly on routine office ultrasound examination resulted in a diagnosis of fetal acrania when targeted ultrasonography was performed by a consultant. Following pregnancy termination, examination of the abortus revealed partial cranial destruction secondary to an amniotic band. It is often difficult to distinguish between anencephaly, acrania, and amniotic band sequence prenatally, but postnatal differentiation is imperative for accurate risk assessment in genetic counseling.

Pregnancy anxieties and natural recognition in baby-switching.

Recent media reports in the USA of baby-switching at birth have caused anxiety for a number of maternity patients. Although alternative precautionary procedures are being implemented by hospitals to prevent baby-switching, ways to allay the maternity patient's anxiety must also be considered. While maternity patients can be expected to recognize their neonates, it is less clear how well they perform recognition under specified conditions. An American team of researchers noted postpartum mothers' anxiety levels and their natural cues to recognize crying sounds and garment smells of their babies as preventive measures against baby-switching. An experimental study design was used to conduct this research. Participants completed a demographic form and Levin's pregnancy anxiety instrument, followed by three recognition challenges for hearing and smelling cues. Ten per cent of mothers reported anxiety about baby-switching, 65.9% recognized their babies from recorded crying, and 52.3% recognized their babies by smell. Mothers do have the natural ability to recognize the cries or smells of their babies, even when anxious about baby-switching. Educating new mothers, acknowledging their natural ability for baby recognition, and promoting the use of private rooms with same-room (couplet) care can serve as extra safeguards.