Is there a correlation between aortic Doppler velocimetric findings in diabetic pregnant women and fetal outcome?

At present, the role of Doppler velocimetry in monitoring fetal well-being in diabetic pregnancies is controversial. The present study was conducted to determine if fetal aortic velocity waveforms were correlated with fetal outcome in pregnancies complicated by diabetes mellitus. Fetal aortic blood flow was prospectively assessed in 30 pregnant women with insulin-dependent diabetes mellitus. Systolic-diastolic ratios were obtained at 2 week intervals between 18 and 38 weeks of gestation. They were analyzed according to several fetal outcome variables. Infants with presumed fetal distress during labor and neonates with respiratory abnormalities (respiratory distress syndrome, persistent fetal circulation, or transient tachypnea of the newborn) showed statistically significant elevations of aortic Doppler indices (P < 0.031 and < 0.011, respectively). However, these correlations lacked clinical relevance. The infants demonstrated no evidence of fetal distress at birth since Apgar scores were > 7 at 5 min in all but one neonate. No relationship was found between the mean third trimester fetal aortic systolic-diastolic ratios and perinatal death, preterm deliveries, birth weight, Apgar scores at 1 and 5 min, and neonatal metabolic abnormalities. These data demonstrate a poor correlation between fetal aortic Doppler waveform analysis and fetal outcome. Therefore, fetal aortic Doppler velocimetry cannot be used as a means of assessing impending fetal compromise in offspring of diabetic mothers.

Fetal Doppler and behavioral responses during hypoglycemia induced with the insulin clamp technique in pregnant diabetic women.

OBJECTIVE: This study was undertaken to assess human fetal behavior and fetal blood flow after insulin-induced symptomatic maternal hypoglycemia of sufficient magnitude to elicit counterregulatory hormones and a symptomatic response. STUDY DESIGN: Plasma glucose was lowered from approximately 95 mg/dl to 45 mg/dl in decrements of 10 mg/dl every 40 minutes with the insulin clamp technique. In 10 insulin-dependent diabetic women in the third trimester, the fetus was studied by monitoring fetal heart rate and recording fetal body and breathing movements and by performing Doppler waveform analysis with real-time ultrasonography. Maternal levels of glucagon, cortisol, epinephrine, and growth hormone were measured at each plasma glucose level. RESULTS: The mean number of fetal limb and body movements at the start of the study was 25 +/- 16 per 15 minutes, which increased to a mean of 38 +/- 28 at a glucose level of 60 mg/dl and then declined to a mean of 23 +/- 10 at a glucose level of approximately 45 mg/dl. These changes, however, did not achieve statistical significance. In addition, no significant reductions in fetal breathing movements or heart rate were observed, although maternal epinephrine and growth hormone levels were significantly (p < 0.001) increased. No consistent changes in Doppler velocity waveforms were observed. CONCLUSION: These data suggest that fetal well-being remains unaltered in spite of moderate maternal hypoglycemia in diabetic women.

Is the risk of perinatal transmission of human immunodeficiency virus increased by the intrapartum use of spiral electrodes or fetal scalp pH sampling?

OBJECTIVE: Our aim was to determine whether the intrapartum use of fetal scalp electrodes or fetal scalp pH sampling increases the rate of perinatal transmission of human immunodeficiency virus. STUDY DESIGN: The rate of perinatal transmission of human immunodeficiency virus in 31 monitored pregnancies was determined, and those pregnancies were compared with a control group of 117 pregnancies. RESULTS: The monitored group was comparable to the control group with respect to maternal age, race, human immunodeficiency virus risk behavior, CD4+ cell count, p24 antigen status, and stage of human immunodeficiency virus disease. The mean gestational age at delivery and the mean birth weight were similar in the monitored group and the control group. The perinatal transmission rate for the monitored group (29.0%) was not statistically different from that of the control group (25.6%). CONCLUSIONS: If confirmed by larger studies, our findings suggest that the intrapartum use of fetal scalp electrodes or fetal scalp pH sampling does not appear to increase the perinatal transmission of human immunodeficiency virus.

Diabetes mellitus in pregnancy and the assessment of umbilical artery waveforms using pulsed Doppler ultrasonography.

The utility of Doppler ultrasonography as a means of assessing potential alterations of vascular resistance prior to fetal or maternal compromise is very attractive. We investigated this relationship by prospectively performing Doppler studies of the fetal umbilical artery in 56 diabetic patients, 14 of whom had varying degrees of vascular complications. When regression curves were established for the S/D ratio, the Pourcelot index, and the resistance index of the fetal umbilical artery, the mean Doppler values were higher in diabetic patients with vasculopathy than in nondiabetic control patients or in diabetic patients without vasculopathy. The third trimester S/D ratio was greater than 3.0 in almost 50% of patients with vasculopathy. A tendency toward adverse outcomes was observed at S/D ratios approaching 4.0. Statistically significant correlations were found between elevated Doppler indices and maternal vasculopathy associated with hypertension and worsening renal insufficiency. Intrauterine growth retardation and neonatal metabolic complications were also significantly correlated with elevated Doppler indices. There was, however, no correlation between Doppler indices and glucose values, although most were within a euglycemic range. The aforementioned data indicate an increased resistance circuit among diabetics with vasculopathy, which may reflect a relative reduction in basal uteroplacental blood flow and the need for cautious interpretation of Doppler indices in these patients.

Do fiber-enriched diabetic diets have glucose-lowering effects in pregnancy?

A fiber-enriched diabetic diet that contained a modest increase in dietary fiber and a commercially available fiber supplement was studied in pregnant diabetic women for its potential glucose-lowering effects. Noninsulin-requiring gestational diabetic patients were placed on a fiber-enriched diet of increasing fiber content starting with 40 gm and eventually achieving a maximum tolerable dose of 80 gm of fiber per day. Initial pilot study demonstrated that patients could not tolerate more than 40 gm of fiber-rich food. Therefore additional fiber was administered via commercially available high-fiber drink. Satisfactory patient acceptance and compliance were achieved using this method. The response curve was flat with no lowering of blood glucose with increasing dietary fiber content. Furthermore, when the group receiving the moderate-fiber dose (40 to 60 gm), the high-fiber dose (70 to 80 gm), and a third group on an American Diabetes Association recommended diet (20 gm or less of fiber) were compared, no significant difference was observed in the mean blood glucose and postprandial glucose levels. This pilot study demonstrates that high-fiber diets, although better tolerated by patients when administered in divided amounts, are not associated with a concomitant lowering of blood glucose levels in pregnant diabetic patients.

Fetal blood sampling in human immunodeficiency virus--seropositive women before elective midtrimester termination of pregnancy.

OBJECTIVES: To explore the diagnostic potential of fetal blood sampling in the prenatal diagnosis of intrauterine human immunodeficiency virus infection and to investigate the transplacental transfer of human immunodeficiency virus antibody and p24 antigen in the second trimester of pregnancy, we studied serum and amniotic fluid obtained from 13 seropositive women and their fetuses before elective termination of pregnancy. STUDY DESIGN: Enzyme-linked immunosorbent assay, Western blot antibody analyses, and p24 antigen assays were performed on all samples. RESULTS: Human immunodeficiency virus antibody was detected by enzyme-linked immunosorbent assay and Western blot analysis in aliquots of maternal serum, amniotic fluid, and fetal serum from all 13 pregnancies. Each mother-fetus pair had identical antibody banding patterns. In contrast, p24 antigen was found in the maternal serum and amniotic fluid samples from five of 13 women (38%) and in serum from only three of 13 fetuses (23%). CONCLUSIONS: We conclude that fetal blood sampling, if combined with sophisticated serologic analysis, may have the potential to provide the diagnosis of congenital infection with human immunodeficiency virus. The correlation of immunologic, virologic, and molecular biologic methods with subsequent infant outcome and risk of iatrogenic infection of the fetus remains to be determined.

Prevalence and prognostic significance of anticardiolipin antibodies in pregnancies complicated by human immunodeficiency virus-1 infection.

OBJECTIVES: Anticardiolipin antibodies are estimated to occur in 2.2% of all pregnancies and are associated with adverse outcomes including thrombotic events, fetal wastage, intrauterine growth retardation, and preterm delivery. We studied 32 human immunodeficiency virus-seropositive gravidas (1) to determine the prevalence of anticardiolipin antibodies in pregnant women infected with human immunodeficiency virus-1 and (2) to investigate the association between the presence of anticardiolipin antibodies and pregnancy outcome, disease status, and perinatal transmission of human immunodeficiency virus-1. STUDY DESIGN: Serum samples obtained at the first prenatal visit were analyzed for anticardiolipin immunoglobulin M and immunoglobulin G by enzyme-linked immunosorbent assay. Relevant antepartum, intrapartum, and postpartum data, including maternal CD4+ lymphocyte subsets, human immunodeficiency virus p24 antigen determinations, Venereal Disease Research Laboratory test, hematocrit, platelet counts, and placental pathologic tissue of the anticardiolipin antibody-positive and anticardiolipin antibody-negative groups were compared. RESULTS: Test results for 17 (53%) of patients were positive for anticardiolipin antibody: 4 had only immunoglobulin M, 1 had only immunoglobulin G, and the remaining 12 had both antibodies. The patients in the anticardiolipin antibody-positive group were delivered of infants with a mean gestational age of 39 weeks and mean birth weight of 2983 gm. In the anticardiolipin antibody-negative group 15 deliveries had a mean gestational age of 36.3 weeks and a mean birth weight of 2330 gm. CONCLUSIONS: We conclude that there is a high prevalence of anticardiolipin antibodies in patients who have human immunodeficiency virus, which is not associated with adverse maternal or neonatal outcome, maternal human immunodeficiency virus status, or perinatal transmission of human immunodeficiency virus-1.

Impairment of counterregulatory hormone responses to hypoglycemia in pregnant women with insulin-dependent diabetes mellitus.

Intensive insulin therapy directed at elimination of hyperglycemia is advocated during pregnancy in women with insulin-dependent diabetes mellitus. Because such treatment is complicated by frequent hypoglycemic episodes, we evaluated maternal and fetal responses in nine intensively treated pregnant women with insulin-dependent diabetes mellitus during an insulin-induced, gradual, controlled fall in plasma glucose levels. In contrast to values in nonpregnant control women, reductions in glucose to 44 +/- 2 mg/dl in pregnant diabetic patients failed to elicit an increase in glucagon levels. Epinephrine release during hypoglycemia was also markedly suppressed in the pregnant diabetic subjects (106 +/- 32 vs 327 +/- 52 pg/ml in controls, p less than 0.001). Furthermore, the plasma glucose level at which epinephrine and growth hormone were released was 5 to 10 mg/dl lower in the pregnant women with insulin-dependent diabetes mellitus (p less than 0.05). The basal fetal heart rate remained unchanged and continued to manifest accelerations during the hypoglycemic state. We conclude that the high frequency of hypoglycemia in intensively treated pregnant women with insulin-dependent diabetes mellitus may be due in part to impaired counterregulatory hormonal responses.

Assessment of carbohydrate tolerance in pregnancy.

A review is given of the various methods of assessing carbohydrate tolerance in pregnancy. Oral glucose tolerance screening and diagnostic tests have been in use for more than 25 years. They are easily administered, relatively inexpensive, and present reasonable sensitivity; therefore, they continue to be used quite extensively. However, lack of reproducibility of the results and side effects such as nausea, vomiting, and headache have led to the use of alternate methods including glucose polymer (Polycose) and standard breakfast meals. These methods have been reported to present satisfactory results in clinical practice. Glycosylated hemoglobin (HbA1c) and fructosamine assays are also alternate forms of testing carbohydrate metabolism HbA1c measurement have been proven insensitive as a screening test for gestational diabetes, while their use as an index of overall glucose control remains valuable. The role of fructosamine in the assessment of carbohydrate intolerance remains controversial with conflicting claims made by various investigators regarding its sensitivity in detecting gestational diabetes and its response to alterations in glycemic control. In this review, the relative advantages and disadvantages of each glucose tolerance test are discussed and recommendations are given regarding their utility in pregnancy.

A longitudinal study comparing growth in diabetic pregnancies with growth in normal gestations: I. The fetal weight.

Diabetes mellitus is associated with fetal growth acceleration and retardation. These aberrations in fetal growth seem to be influenced by a variety of factors including vascular disease, glycemic control, hypertension and smoking. In order to characterize fetal growth under the above conditions, longitudinal sonographic evaluations were performed in 52 pregnant, insulin-dependent diabetic women with the usual monitoring of the patients' metabolic control. Regression analyses revealed that vascular disease and glycemic conditions were the most important influences for growth, with manifestation beyond the second trimester. With stringent glucose control (mean whole blood less than or equal to 100 mg/dl) in the absence of vasculopathy (white classes A, B, C), fetal growth was similar to that in normal pregnancies. In the presence of vasculopathy (white classes D and FR), growth was reduced, especially when near-normal glycemic levels were achieved. Conversely, in poorly controlled diabetic women, enhanced fetal growth were observed in patients with and without vasculopathy. No aberrations in fetal growth were observed, however, before the third trimester. The findings of our study demonstrate that vasculopathy and glycemia are dominant and independent regulators of fetal growth. However, their influences are not manifested in growth changes before the third trimester.

Sonographic assessment of growth of the fetal head in diabetic pregnancies compared with normal gestations.

A longitudinal ultrasound study was conducted in 45 insulin-dependent diabetic patients who maintained good glycemic control (mean plasma glucose less than 120 mg/dl) throughout most of their pregnancy in order to assess growth of the fetal head in the presence of euglycemia. Patients with and without vasculopathy were found to be comparable with regard to their glycemic control, medical and obstetric complications, as well as incremental growth and the velocity of growth of the fetal biparietal diameter (BPD). When compared with the control group, the velocity of growth of the BPD was not significantly different throughout pregnancy. However, the actual increment in BPD growth remained less than that of the control fetuses, especially during the second trimester when a significant statistical difference was found. Possible explanations may include delayed ovulation, reduced growth velocity in the first trimester, or constitutionally smaller embryos among the diabetic group. The pattern of BPD growth among diabetics was best described by a third degree polynomial regression equation. These results demonstrate that in well-controlled diabetics, although the increment in BPD was less than controls, the growth pattern of the fetal BPD was similar among the White classes B to FR, and the velocity of growth of the BPD was similar among diabetics and nondiabetics.

Dating through pregnancy: a measure of growing up.

The accurate estimation of gestational age is an essential part of pregnancy management, since the consequences of erroneous dating carry increased risks of perinatal morbidity and mortality. Ultrasonography offers a unique opportunity to objectively measure quantitative changes in growth increments of various fetal structures, as well as qualitative changes occurring near term which are indicative of fetal maturity. Therefore, dating through pregnancy is possible by the use of various parameters such as the crown-rump length, the trunk circumference, and the biparietal diameter in the first trimester; the biparietal diameter, the cerebellum, orbital distance, clavicular length, lengths of the long bones of the upper and lower extremities, and the foot length in the second and third trimesters; and the indices of maturity in the late third trimester such as colonic grading and epiphyseal ossification centers of the long bones of the upper and lower extremities. Using a combination of fetal biometry and maturity indices permit dating through pregnancy as a measure of growing up.

Diagnostic fetal umbilical blood sampling in the management of isoimmunization.

Current management of isoimmunization in pregnancy is predicted on the assumption that all sensitized women carry antigen-positive fetuses. In addition, management is based on indirect predictors of the magnitude of the fetal hemolytic disease. We present a preliminary report using a new approach of direct fetal blood sampling for the diagnosis and treatment of these patients. This form of evaluation provides specific information about fetal red blood cell antigen status and the degree of fetal anemia at an earlier gestational age than that validated by the Liley curves and eliminates empiricism from both the diagnosis and treatment of the isoimmunized pregnancy. The use of such a management protocol reduces the need for multiple invasive procedures in fetuses at little risk for disease and provides specific information about the status of those fetuses truly at risk.