Diagnostic accuracy of elastography and scintigraphic imaging after thermal microwave ablation of thyroid nodules.

PURPOSE: The aim of this study is to evaluate structural alterations of thyroid tissue after microwave ablation using elastography and scintigraphic imaging to investigate the applicability of these diagnostic methods for follow-up.  MATERIALS AND METHODS: 35 patients with 39 thyroid nodules were evaluated using elastography and scintigraphic imaging before and after ultrasound-guided microwave ablation. Elastography was analyzed according to color-coded output and results were classified using a fourfold elasticity score (ES). Nodules color-coded blue were classified ES1 for high elasticity through ES2 and ES3 for lower elasticity, and nodules with very low elasticity were color-coded red and classified as ES4. (99m)Tc-pertechnetate served as a tracer for scintigraphic imaging of hot and indifferent nodules and (99m)Tc-MIBI for cold nodules. RESULTS: Before microwave ablation, elastography detected a median elasticity score of ES 2 ±â€Š0.7, and after ablation the median score was ES 3 ±â€Š0.6. Overall, the median score increased by 1ES ±â€Š0.6 (p < 0.01). Scintigraphic imaging detected a median reduction of tracer uptake in ablated tissue of 38.7 %±â€Š27.5(p < 0.01). (99m)Tc-pertechnetate scans showed a median decrease of tracer uptake of 26.3 %±â€Š16.3 and (99m)Tc-MIBI scans detected uptake reduction of 54.7 %±â€Š29.2. CONCLUSION: Scintigraphic imaging using (99m)Tc-pertechnetate and (99m)Tc-MIBI provides quantifiable results and is promising as a diagnostic follow-up after microwave ablation. Strain elastography detects decreasing tissue elasticity, but accuracy is limited by the necessary reduction of color-coded output to elasticity scores.

Impact of smoking on the duration of breastfeeding in mothers with insulin-dependent diabetes mellitus.

UNLABELLED: The effect of smoking on breastfeeding was studied in 252 mothers with insulin-dependent diabetes mellitus (IDDM) giving birth in the period 1985-1995 and of whom 31% were classified as White group B, 16% group C, 37% group D and 16% group F or R. As part of a centralized regimen a detailed smoking history was taken during pregnancy. Forty-six percent were smokers. In 1997, a questionnaire was sent out asking for information on the duration of breastfeeding. The response rate was 87%. The duration of breastfeeding was significantly longer in the non-smoking group (p = 0.004). Fifty-five percent of non-smokers versus 33% of smokers were still breastfeeding 4 mo after birth. A strong dose-response relationship was established (p = 0.009). Cox multiple regression analysis showed a significantly negative influence of smoking (p = 0.01) and of hospitalization of the infants during the first year of life (p = 0.02) and a significantly positive influence of maternal age (p = 0.02) and birthweight (p = 0.03) on the length of breastfeeding. The breastfeeding curves for non-smokers and smokers were mainly divergent in the first month after birth, suggesting that the effect of smoking on breastfeeding is mainly exerted during that period. CONCLUSION: Smoking exerted a strong, negative, dose-dependent influence on breastfeeding duration in mothers with IDDM. Given the hazards of smoking, the advantages of breastfeeding and the possible link between being breastfed and later development of diabetes mellitus, these results should be taken into consideration when counselling pregnant women with IDDM about smoking.

Association of polymorphism of methylene-tetrahydro-folate-reductase with urinary albumin excretion rate in type 1 diabetes mellitus but not with preeclampsia, retinopathy, and preterm delivery.

AIM: The genetic setting is a potential risk factor for dysfunction of vascular endothelial cells. The prevalence of polymorphism in the methylene-tetrahydro-folate-reductase (MTHFR) gene (677C-->T) was evaluated in diabetic pregnancy complicated by preeclampsia, nephropathy, retinopathy, and preterm delivery. The role of hyperhomocysteinemia in microangiopathy in diabetes mellitus has been debated and is mainly seen with reduced activity of the MTHFR gene. A polymorphism in the gene for MTHFR is identified causing this phenomenon. DESIGN: Two hundred and sixty-eight pregnant women with type 1 diabetes mellitus were recruited. Two hundred and thirty-three women were successfully analyzed for MTHFR gene polymorphism 677C-->T and compared to the incidence of the polymorphism in the background population (n=1084). The pregnancy data charts were reviewed retrospectively. RESULTS: The frequency of the MTHFR polymorphism in the background population was 29% and the heterozygozity 42%. The women with type 1 diabetes mellitus had a higher frequency of the MTHFR polymorphism with 52% heterozygotes and 9% homozygotes than had the background population (heterozygotes, background vs. type 1 diabetes mellitus: chi(2)=14, df=1, p<0.0002). The odds ratio for heterozygozity of the MTHFR polymorphism was 1.8 (95% Cl: 1.3-2.4) in women with type 1 diabetes mellitus. Women with either micro- or macroalbuminuria had a higher frequency of MTHFR polymorphism with 61% heterozygotes and 3% homozygotes than had the background population (heterozygotes: chi(2)=8.9, df=1, p<0.01). The odds ratio for heterozygozity of the MTHFR polymorphism was 2.3 (95% CI: 1.4-4) in women with type 1 diabetes mellitus. CONCLUSION: An association was demonstrated between the MTHFR polymorphism and type 1 diabetes mellitus as well as increasing albumin excretion rate in pregnant women.

Clinical impact of mild carbohydrate intolerance in pregnancy: a study of 2904 nondiabetic Danish women with risk factors for gestational diabetes mellitus.

OBJECTIVE: The objective was to study the clinical impact of mild carbohydrate intolerance in pregnant women with risk factors for gestational diabetes mellitus. STUDY DESIGN: This was a historical cohort study of 2904 pregnant women examined for gestational diabetes on the basis of risk factors. Information on oral glucose tolerance test results and clinical outcomes was collected from laboratory charts and medical records. RESULTS: The following outcomes increased significantly with increasing glucose values during the oral glucose tolerance test: shoulder dystocia, macrosomia, emergency cesarean section, assisted delivery, hypertension, and induction of labor. However, when corrections were made for other risk factors, hypertension and induction of labor were only marginally associated with glucose levels. CONCLUSION: In a group of nondiabetic pregnant women with risk factors for gestational diabetes, there was a graded increase in the frequency of shoulder dystocia and other maternal-fetal complications with increasing glucose levels during an oral glucose tolerance test.

Serum leptin levels in pregnant women with type 1 diabetes mellitus.

BACKGROUND: Leptin is an important weight regulator and during pregnancy leptin is not only synthesized in adipose tissue but also in the placenta. AIM: To examine changes in serum leptin levels in women with type 1 diabetes mellitus during pregnancy and post delivery in relation to concomitant changes in maternal body weight, birth weight, glycemic control, and blood pressure. METHODS: Non-fasting serum leptin from 45 women with type 1 diabetes mellitus were studied consecutively throughout pregnancy and 3 months post partum. RESULTS: Serum leptin was positively associated with HbA1c in week 18, 22 and 30 (r=0.38, 0.41, and 0.54, respectively, p<0.05, adjusted for body weight). Moreover, serum leptin correlated positively with maternal body weight and BMI (0.4525 kg/m2), the changes during pregnancy and the level of serum leptin were significantly greater compared to lean women (p<0.05). The women with low ambulatory blood pressure (lower tertile, mean arterial blood pressure <83.4 mmHg) showed the lowest level of serum leptin throughout pregnancy and it changed significantly differently from the women with higher blood pressure (p<0.05). CONCLUSION: Changes in serum leptin levels of pregnant women with type 1 diabetes mellitus were associated with parallel changes in maternal body weight and glycemic control. Women with low blood pressure had the lowest serum leptin levels throughout pregnancy.

Effect of a high monounsaturated fatty acid diet on blood pressure and glucose metabolism in women with gestational diabetes mellitus.

OBJECTIVE: The effect of a diet rich in monounsaturated fatty acids (MUFA) on blood pressure, glycemic control, lipids and insulin sensitivity was evaluated in women with gestational diabetes mellitus. DESIGN AND METHODS: A randomized, unpaired diet intervention was performed in 27 women with gestational diabetes mellitus in an outpatient clinic. After randomization the women received either a high-carbohydrate diet (H-CHO) or a high-MUFA diet (H-MUFA) from the 33rd gestational week of pregnancy. Outcome measures were 24 h ambulatory blood pressure, blood lipids, glycemic control and insulin sensitivity estimated by an intravenous glucose tolerance test. RESULTS: The 24 h diastolic blood pressure increased more in the H-CHO group than in the H-MUFA group (P<0.04). CONCLUSIONS: After 5 weeks of treatment with a MUFA-enriched diet, no increase in 24 h diastolic blood pressure and no adverse effects on blood lipids were seen. The favorable effect on the blood pressure by the MUFA diet is a possible non-medication treatment. The H-MUFA diet had no advantage to the H-CHO diet in ameliorating the decline of insulin sensitivity in third term of pregnancy in GDM.

Macrosomia associated with maternal serum insulin-like growth factor-I and -II in diabetic pregnancy.

OBJECTIVE: To determine the possible relation between maternal serum insulin-like growth factor I and II (IGF-I and IGF-II) in women with insulin-dependent diabetes mellitus and fetal macrosomia. METHODS: This was a prospective, observational study of 45 pregnant women with insulin-dependent diabetes mellitus without overt nephropathy, examined in an outpatient, antenatal diabetic clinic. Maternal venous serum samples were collected from week 14 every fourth week until week 30, and every other week until delivery. Levels of IGF-I and -II were measured in maternal serum by immunoassays. The repeated measurements were tested with two-way analysis of variance. The outcome measures were birth weight and serum IGF-I, IGF-II, IGF binding protein (BP)-3, and IGFBP-3 proteases. Before the study, minimum sampling size was calculated as 14 subjects in each group if a difference in IGF-I of 50 microg/L was to be detected with an estimated standard deviation of 40, a two-sided P value (alpha) of.05, and a power of 90 (beta =.1). RESULTS: Increasing levels of IGF-I and -II were significantly associated with the birth-weight groups: The higher the birth-weight ratio, the higher the levels of IGF-I and -II (P <.01). CONCLUSION: Macrosomia in diabetic pregnancy is associated with high levels of maternal IGF-I and -II.

Ambulatory blood pressure as predictor of preeclampsia in diabetic pregnancies with respect to urinary albumin excretion rate and glycemic regulation.

BACKGROUND: Twenty-four-hour ambulatory blood pressure was evaluated as a predictor of preeclampsia in women with insulin-dependent diabetes mellitus with respect to urinary albumin excretion rate and glycemic regulation. METHODS: One hundred and fifty-one women with insulin-dependent diabetes mellitus were consecutively recruited from the outpatient maternity ward for 24 hour ambulatory blood pressure measurement with a portable monitor (SpaceLab 90207). Blood pressure was measured three times during pregnancy and once after delivery. Evaluation was performed with receiver-operator-characteristics curves in primiparous women. Stratified analysis and multiple regression was applied with respect to urinary albumin excretion rate, HbA1c, age, duration of diabetes mellitus, uric acid, and BMI. RESULTS: The incidence of preeclampsia was significantly associated with increasing urinary albumin excretion rate, primiparity, and ambulatory blood pressure. Ambulatory blood pressure was associated with HbA1c throughout pregnancy adjusted for urinary albumin excretion rate. The ambulatory blood pressure was higher from first trimester throughout pregnancy in women developing preeclampsia compared to women who did not have preeclampsia. The best sensitivity and specificity for predicting preeclampsia in primiparous women were at cut-off values of systolic and diastolic day ambulatory blood pressure above 122 and 74 mmHg, respectively. The relative risk of preeclampsia was significantly higher when ambulatory blood pressure was above the cut-off values and increased further with higher urinary albumin excretion rate. CONCLUSIONS: The relationship between ambulatory blood pressure and preeclampsia is not confined to women with macroalbuminuria but is also present in women with normo- and microalbuminuria. Poor glycemic control and increased urinary albumin excretion rate is associated with preeclampsia when ambulatory blood pressure is above cut-off values of 122/74 mmHg (systole/diastole). Ambulatory blood pressure is a reliable measurement for prediction of preeclampsia in primiparous women with insulin-dependent diabetes mellitus.

Diabetic retinopathy in pregnancy during tight metabolic control.

BACKGROUND: The relation between retinopathy and the parameters: 24-h blood pressure, glucose control, albuminuria, and outcome of pregnancy was studied before, during, and after pregnancy in women with insulin-dependent diabetes mellitus on tight metabolic control during pregnancy. METHODS: Prospective study of 112 pregnant women with insulin-dependent diabetes mellitus followed with fundus photography at the Department of Ophthalmology, Arhus University Hospital. Changes in retinopathy were related to 24-h blood pressure, blood glucose, albuminuria, and adverse perinatal outcome. RESULTS: There was an association between grade of retinopathy and HbAlc before (Spearman's rho=0.49, p<0.04) and after pregnancy (Spearman's rho=0.42, p<0.02), but no such correlation was found at any examination during pregnancy where glycemia was kept tight. Those women who had progression of retinopathy during or after pregnancy had significantly earlier onset of diabetes mellitus (14+/-8 years, range 1-27) than those women with improvement or no progression of retinopathy (19+/-8 years, range 1-36, p<0.04). No association was found between progression of retinopathy and HbA1c, blood pressure, adverse perinatal outcome or any of the other variables studied. CONCLUSIONS: Tight glycemic control during pregnancy is recommendable to avoid progression of retinopathy. Attention should be given to the period after delivery where the tight regulation may be difficult to achieve. IDDM women should be encouraged to plan pregnancies early in life.

Birthweight in women with potential gestational diabetes mellitus--an effect of obesity rather than glucose intolerance?

BACKGROUND: The purpose was to compare the influence of varying levels of glycemia on the perinatal outcome. METHODS: The data charts of 383 women screened for gestational diabetes mellitus with an oral glucose tolerance test during two birthyears were retrospectively evaluated. In 55 women gestational diabetes mellitus was diagnosed and treated with diet. The non-diabetic women (n=328) were subdivided into a borderline diabetes group (n=74) and a normal group (n= 254) on the basis of the oral glucose tolerance test result. The birth registry of 8196 singleton pregnancies from The Perinatal Research Unit at Skejby University Hospital served as the background population. RESULTS: Birthweight was highest in the borderline group. Weight increase during pregnancy was larger in the non-diabetic than the gestational diabetic women (15 vs. 8 kg p<0.01). The women with less increase of body weight delivered neonates with lower birthweight than those with higher increase. Birthweight was associated with maternal weight during pregnancy (p<0.01). Birthweight ratio increased with increasing glucose intolerance. Vaginal delivery rate was less and cesarean section rate higher in women with gestational diabetes mellitus compared to the non-diabetic women. No significant difference was found in the incidence of hypertensive disorders during pregnancy or neonatal morbidity. CONCLUSIONS: Even minor hyperglycemia is associated with increasing birthweight. Birthweight is reduced in GDM when dietary treatment is instituted and effect on weight gain is achieved.

Phosphorylated insulin-like growth factor binding protein 1 is increased in pregnant diabetic subjects.

During pregnancy, IGFs and their binding proteins (IGFBPs) are important for the growth of fetal and maternal tissues. IGFBP-1 normally circulates as a single, highly phosphorylated species (hpIGFBP-1). However, in pregnancy there are lesser phosphorylated isoforms (lpIGFBP-1) with decreased affinity for IGF-I, allowing for increased IGF bioavailability. Because regulation of IGFBP-1 is abnormal in type 1 diabetes, we examined the impact of this on IGFBP-1 and its phosphorylation status in diabetic pregnancy. We assessed IGFBP-1 in relation to birth weight, maternal weight gain, duration of diabetes, glycemic control, and the presence or absence of retinopathy in 44 diabetic and 11 nondiabetic subjects. We found that in type 1 diabetic patients there was a significant negative relationship between hpIGFBP-1 and birth weight (r = -0.42, P < 0.01) and between the ratio of hpIGFBP-1 to lpIGFBP-1 and birth weight (r = -0.38, P = 0.02) by week 18 of gestation. Multiple regression analysis confirmed that hpIGFBP-1 was the best single predictor of birth weight (R2 = 0.3, P = 0.001) in diabetic subjects using models including other parameters known to influence fetal size. In contrast to hpIGFBP-1 levels, lpIGFBP-1 levels were not associated with birth weight, but were significantly related to initial maternal BMI and maternal weight throughout gestation in diabetic subjects (r = -0.57, P < 0.001). hpIGFBP-1 levels were positively related to duration of diabetes (r = 0.38, P < 0.01). Diabetic subjects had significantly higher hpIGFBP-1 and lpIGFBP-1 levels than nondiabetic subjects (hpIGFBP-1: 215 +/- 21 vs. 108 +/- 13 microg/l, P = 0.01; lpIGFBP-1: 139 +/- 12 vs. 66 +/- 5 microg/l, P < 0.001), but the ratio of hpIGFBP-1 to lpIGFBP-1 was similar in both groups (2.1 +/- 0.3 [diabetic] vs. 1.7 +/- 0.2 [nondiabetic], NS). In summary, maternal IGFBP-1 levels were higher in diabetic than in normal pregnancies. Diabetic subjects with prolonged duration of diabetes and retinopathy had higher total IGFBP-1 levels than those with shorter disease duration. Thus hpIGFBP-1 in diabetic pregnancy is positively related to the duration of diabetes and inversely related to fetal growth, with lpIGFBP-1 being related to maternal weight and BMI. The ratio of hpIGFBP-1 to lpIGFBP-1 may be a more robust indicator of fetal outcome, since it was consistent between diabetic and nondiabetic subjects. Measurement of the different phosphorylated isoforms of IGFBP-1 may increase the usefulness of IGFBP-1 as a predictor of fetal growth in both normal and diabetic pregnancy.

Pregnancies complicated by diabetic proliferative retinopathy.

BACKGROUND: To examine retinal and pregnancy outcome in insulin-dependent diabetic women with proliferative retinopathy and assess the effect of albuminuria on morbidity. METHODS: The records of 26 women with known proliferative retinopathy before pregnancy were studied retrospectively in the prepregnancy period, during pregnancy, and after delivery. Perinatal and maternal morbidity was studied using ophthalmic, obstetric and pediatric records. RESULTS: Seven pregnancies were delivered preterm (27%). Serious neonatal morbidity occurred in five pregnancies (19%). Perinatal survival was 88%. Laser treatment was given prior to pregnancy to 54%, during pregnancy to 27% and after delivery to 31% of the women. Laser treatment during pregnancy was more common in those with no prior photocoagulation and in White class F/R. Low birthweight was more frequently associated with nephropathy and proliferative retinopathy compared to retinopathy alone (p<0.05). Recent hemorrhage, maculopathy or glaucoma was found in 14 (54%) of the women. Blindness developed unilaterally in two women. CONCLUSIONS: Perinatal morbidity was associated with nephropathy rather than retinopathy. The incidence of hemorrhage, maculopathy or glaucoma was similar in White classes R and F/R.

Changes in kidney volume during pregnancy in non-diabetic and diabetic rats measured by magnetic resonance imaging.

Consecutive magnetic resonance images were obtained in pregnant animals and their respective controls, and changes in kidney, cortex, medulla, and pelvis volumes were calculated. In non-diabetic pregnant animals, a marked increase in kidney and cortex volumes was observed within the first 15 days of pregnancy (29 and 20%, respectively), while no significant changes were seen in medulla or pelvic volumes. Five days later (near term) and after delivery, kidney and cortex volumes had decreased to values before pregnancy. In pregnant diabetic animals, a 26% increase in renal volume was seen over the first 15 days of pregnancy when compared to the increase seen in non-diabetic pregnant animals. Pregnant diabetic animals had a parallel increase in cortex and medulla volumes, but still no changes in the pelvis volume. In contrast to non-diabetic pregnant animals a non-heterogeneous pattern in renal volume was seen post partum, as not all animals normalized their renal volume.

[Changes in glucose metabolism in gestational diabetes mellitus during and after pregnancy]. / Forandringer i glukosestofskiftet ved gestationel diabetes mellitus under og efter graviditet.

Twenty-nine pregnant women with gestational diabetes mellitus (GDM) diagnosed before the 34th gestational week had three intravenous glucose tolerance tests (IVGTT) performed during pregnancy and a follow-up with OGTT post partum. The women with a normal OGTT post partum had a significant decrease in fasting serum glucose from the 33rd to the 38th week in pregnancy (4.8-->4.0 mmol/l, p < 0.05). However, the women with a diabetic/borderline OGTT showed no decrease in fasting serum glucose during the same period (5.1-->5.0 mmol/l). The K-value (the diminution rate of blood glucose) of the IVGTT in week 38 was significantly lower in women with puerperal diabetic/borderline OGTT compared with women with a normal post partum OGTT (1.05 +/- 0.07 vs. 1.32 +/- 0.08 -10(2) x mmol/l x min-1, respectively, p < 0.05). Diabetic or borderline diabetic OGTT in the first week post partum was significantly associated with a decrease in the K-value from week 33 to 38 (p < 0.05). Early diagnosis of GDM was found to be associated with a pathological OGTT post partum (p < 0.05). Five of 22 women (23%) with previous GDM had a diabetic and one (5%) a borderline OGTT at follow-up four to thirteen months post partum. High fasting serum glucose levels during the last trimester in GDM can identify the women at risk of diabetic/borderline OGTT post partum.

Increased levels of serum fibroblast growth factor-2 in diabetic pregnant women with retinopathy.

Fibroblast growth factor-2 (FGF-2) is a potent mitogen and angiogenic factor normally absent from the adult circulation. We have previously shown that it appears in normal maternal serum and that circulating FGF-2 levels are elevated in pregnancies complicated by diabetes. This study was performed to determine whether serum FGF-2 is more abundant in pregnant diabetic women with retinopathy than in those without. Serum was collected monthly between 14-30 weeks gestation and every 2 weeks from then until delivery (35-38 weeks) from 36 women with type 1 diabetes. FGF-2 was extracted by heparin-Sepharose affinity chromatography and quantified by specific RIA. Patients were divided according to the White classification of diabetes. In 17 women without retinopathy (White groups B, C, and D0), immunoreactive FGF-2 was detectable at 14 weeks (mean +/- SEM, 154 +/- 39 pmol/L), was maximal after 26 weeks (306 +/- 38 pmol/L), after which values steadily declined to term (212 +/- 48 pmol/L). In 19 women with simplex or proliferative retinopathy (White groups D+ and R), circulating levels of FGF-2 were significantly greater between 22-32 weeks gestation (22 weeks, 480 +/- 102 vs. 239 +/- 38 pmol/L; P < 0.05). Serum FGF-2 was significantly correlated with hemoglobin A1c levels at 22, 30, and 34 weeks gestation. The mean birth weight of the infants did not significantly differ between groups. Macroalbuminuria was absent in all patients, and creatinine clearance and blood pressure did not significantly differ between the two groups. The results suggest that serum FGF-2 is substantially elevated in pregnant diabetic women with retinopathy in second and early third trimesters. It is unlikely that in these patients this was primarily due to altered FGF-2 clearance, but may relate to excessive production by the utero-placental compartment. The high circulating levels of FGF-2 may be causally related to the development of diabetic retinopathy.

Renal growth during pregnancy in insulin-dependent diabetic women. A prospective study of renal volume and clinical variables.

Kidney volume was measured during pregnancy in insulin-dependent diabetic women by an ultrasound technique and prognostic value of these measurements evaluated. A prospective study was performed on 87 pregnant women with insulin-dependent diabetes attending the maternity clinic of Aarhus Kommunehospital. Patients with proliferative retinopathy alone, hydronephrosis, or nephrotic syndrome were excluded. The patients were grouped according to onset and duration of diabetes and to vascular lesions; group I (n = 35, White class B+C), group II (n = 11, White class D0), group III (n = 26, White class D+), and group IV (n = 15, White class F+F/R). The patients visited the hospital every 2 weeks during pregnancy for general obstetric and glycaemic control and blood sampling. The volume of both kidneys was measured by a computerized nephrosonograph during the three terms of pregnancy, the puerperium and 4 months postpartum. The kidney volume increased significantly in all four groups from first to third trimester. In the third trimester the kidney volumes were 375 +/- 68 ml (I), 341 +/- 50 ml (II), 362 +/- 63 ml (III), and 343 +/- 54 ml (IV). The kidney volume in the third trimester was positively correlated with creatinine clearance (r = 0.33, P < 0.01) and inversely correlated with creatinine in serum (r = -0.27, P = < 0.02). Total kidney volume decrease (in percent) defined as the difference of maximal volume and value at 4 months postpartum was inversely correlated to albuminuria in the third trimester (r = -0.25, P < 0.05) and vascular lesions of the patients: (mean +/- SEM) 37 +/- 4% (I), 25 +/- 7% (II), 19 +/- 5% (III), and 11 +/- 7% (IV), P < 0.01. In the puerperium, kidney volume decreased significantly from third trimester in groups I, II, and III, whereas we observed no change in group IV. Six of 15 women in groups II and III with kidney volume < 300 ml and normoalbuminuria in the first trimester developed persistent microalbuminuria after pregnancy (P < 0.02). The renal volume in insulin-dependent diabetic women increases significantly during pregnancy and is inversely related to the vascular lesions of the patients. The decrease in renal volume after pregnancy is related to the albuminuria at the end of pregnancy. Women with longstanding diabetes, White class D (= groups II+III), and kidney volume < 300 ml in the first trimester have a high risk of developing permanent microalbuminuria after pregnancy.

Growth and maturation of villi in placentae from well-controlled diabetic women.

Placentae from controls and two groups of diabetic women (one White classes A, B, C and the other classes D, F/R) were collected at 37-42 weeks of gestation. Tissue sections were analysed using stereological methods in order to quantify the growth and maturational status of villi. Birth and placental weights were recorded and placentae sampled in a systematic manner. Fields of view on formalin-fixed, paraffin-embedded sections were analysed to obtain estimates of volumes, surface areas, lengths and diffusion (harmonic mean) distances. Comparisons were drawn using three-way analyses of variance with group, mode of delivery and sex of newborn as the principal effects. Mean weights were similar in controls and diabetic groups. Diabetic placentae had a more voluminous fetal capillary bed of greater length, diameter and surface area. In addition, the diffusion distances across fetal plasma (erythrocyte to endothelium) were shorter. Stromal diffusion distance and villous diameter were greater in vaginal deliveries. Interaction effects influenced also villous capillarization, capillary volume, capillary diameter, trophoblast thickness and stromal thickness. Our results emphasize the importance of adaptations on the fetal side of the diabetic placenta. They show that changes can affect the placentae of appropriate-for-age as well as large-for-age babies and provide no evidence that they increase with the severity and duration of diabetes.

The effects of mode of delivery and sex of newborn on placental morphology in control and diabetic pregnancies.

Placentae from control and diabetic subjects were analysed using stereological techniques in order to assess the effects of mode of delivery (vaginal versus caesarean) and sex of neonate on parenchymal morphology. Effects were assessed using indices of peripheral villous and fetal capillary growth, villous maturity, extent of maternal intervillous space and thickness of intervascular tissue layers. Placentae were from pregnancies (37-42 wk) which were either uncomplicated (control group) or complicated by diabetes mellitus (diabetic group, White class D) which was reasonably well controlled in terms of glucose and glycated haemoglobin levels. Neonatal and placental weights were recorded and placentae sampled in a systematic random fashion. Fields of view on formalin-fixed, paraffin-embedded sections were analysed to obtain estimates of volumes, surface areas, lengths and diffusion (harmonic mean) distances. Comparisons were drawn using 3-way analyses of variance with group, mode of delivery and sex as the principal effects. The mean length of gestation was 2 wk longer in controls (39 versus 37 wk). Despite this, mean birth weight was similar (3.5 kg) in control and diabetic groups. Moreover, diabetic placentae were 17% heavier and showed shorter fetal plasma distances (30%) and larger fetal capillaries (volume 45%, surface 39% and length 30% greater). Mode of delivery had significant main and interaction effects on stromal diffusion distance (25% greater in vaginal deliveries) and an interaction effect on fetal capillary volume. Sex had significant main effects on the maternal plasma distance (21% greater in males) and capillary volume (30% bigger in males) and an interaction effect on placental weight and mean capillary diameter.(ABSTRACT TRUNCATED AT 250 WORDS)

Oxygen diffusive conductance in placentae from control and diabetic women.

Random tissue sections of placentae from control and diabetic deliveries were analysed stereologically. The aim was to test whether or not adaptations in oxygen diffusive conductances occur to help compensate for fetal hypoxic stress in utero. Organs were from 34 control and 55 diabetic deliveries (39 from White's classes A, B, C and 16 from classes D, F/R) arranged in two major groups (ABC and DFR). Tissue samples were fixed in formalin and processed for wax histology. Stereological and physicochemical quantities were used to calculate the partial conductances of six tissue layers, viz. maternal erythrocytes and plasma, villous trophoblast, villous stroma, fetal plasma and fetal erythrocytes. From partial conductances and birthweights, total and specific conductances for each placenta were determined. No differences were detected between diabetic placentae in different classes (A, B, C, D, F/R). However, both the ABC and DFR groups of diabetic placentae had higher total diffusive conductances than control organs. The increase was in the order of 7-25% and persisted even when adjustments were made for apparent differences in birthweights. The principal contributors to these changes were the post-trophoblastic (fetally located) tissue layers. These findings suggest that the diabetic placenta adapts to facilitate the diffusion of oxygen across the placenta and, thereby, to assist the hypoxic fetus.