Prevention of congenital malformations in infants of insulin-dependent diabetic mothers

Dose-response effects of glucose, insulin, and glucagon on mouse pre-embryo development

The diabetic state, as well as elevated culture media glucose level (950 mg D-glucose/dL) per se, significantly retards in vitro development of mouse pre-implantation embryos from a two-cell stage to blastocyst stage; maternal insulin therapy to diabetic mice reverses this impairment. This study was undertaken to assess (1) whether less extreme elevation of the media glucose concentration would also impair development, and (2) whether elevated culture media insulin or glucagon levels would alter development. Two-cell pre-embryos were recovered from B6C3F1 mice that had been stimulated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hGG), mated, and killed 48 hours later. Pre-embryos were observed in culture at 24-hour intervals for a total of 72 hours at four glucose levels: 110 (n = 108), 220 (n = 101), 440 (n = 65), and 950 (n = 106) mg D-glucose/dL. Impairment in progression of development was noted at each time period; compared with development in 110 mg glucose/dL, the distribution of development was significantly different at 24 hours (chi 2 = 60.1, P less than .001), at 48 hours (chi 2 = 36.7, P less than .001), and at 72 hours (chi 2 = 45.1, P less than .001). Rate of development as assessed by ANOVA was also significantly reduced at increasing glucose levels (P less than .0001), with Duncan Multiple Range test demonstrating differences between development at higher glucose levels in the comparison of development in 110 mg/dL versus 440 mg/dL and 950 mg/dL, and at 220 mg/dL versus 950 mg/dL.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypothermia: teratogenic and protective effects on the development of mouse embryos in vitro

Hypothermia often occurs in association with clinical conditions involving severe hypoglycemia, but its effect on embryonic development has not been well evaluated. Thus, the whole embryo culture method was used to expose day 9 (neurulating) and day 10 (early limb bud stage) mouse embryos to physiologic levels of hypothermia (35 degrees C and 32 degrees C) for 4 and 24 hr. Embryos were evaluated after 24 hours for growth and malformations and compared with controls grown at 37 degrees C. Lactate production was measured in embryos cultured for 4 hr at 32 degrees C and compared with those cultured at 37 degrees C. A 4-hr exposure to hypothermia produced little effect morphologically but reduced the rate of lactate production at both embryonic stages. A 24-hr exposure to hypothermia at 35 degrees C or 32 degrees C produced growth retardation and dysmorphogenesis in embryos undergoing neurulation. Early limb bud stage embryos were less sensitive to this treatment, with growth retardation produced only at the lower temperature. Since hypothermia is commonly associated with severe hypoglycemia in cases of diabetic insulin overdose, day 9 (neurulating) mouse embryos were exposed concurrently to short periods of hypothermia and hypoglycemia and compared with embryos cultured in hypoglycemic medium at normal temperature. The results demonstrate that hypothermia partially protects embryos against the dysmorphogenic effects of hypoglycemia. A balance of metabolic rate and available substrate is discussed as a possible mechanism for this protective effect.

Prevention of macrosomia

In summary, appropriate assignment of patients to treatment modality utilizing verified blood glucose determination and targeting mean blood glucose level throughout pregnancy to 5.3 mmol/l (similar to normal nondiabetic blood glucose levels) will result in neonatal size comparable to the general population. Today, we have the knowledge and the technology not only to strive for the target but also, more importantly, to achieve the goal of pregnancy outcome in the diabetic comparable to the non-diabetic population. To return to our original research question: Is it glucose or insufficient knowledge of the management approach that maintains macrosomia levels? It is evident that glucose is the prime cause of macrosomia, although other nutrients have a secondary role. Proper management of glucose abnormality will result in a significant decrease in the rate of macrosomia.

Spontaneous abortion and congenital malformations in diabetes

The first few weeks after conception are a critical period for the embryo of a diabetic mother. If the mother is in good glycaemic control during this time, the risk of spontaneous abortion or major congenital malformation is low. Otherwise, the risk increases in proportion to the degree of blood glucose elevation. Glycohaemoglobin determination in the first trimester can be useful in retrospectively evaluating the degree of glycaemic control present around the time of conception and in roughly estimating the risk of spontaneous abortion or major malformation. For women with high risk, early prenatal diagnosis of congenital anomalies is warranted using detailed ultrasound examination, fetal echocardiography and alpha-fetoprotein determinations. Encouraging diabetic women to achieve strict control prior to conception should virtually eliminate the excess risk of spontaneous abortion or major malformation.

Birthweight of babies born to mothers with type 1 diabetes: is it related to blood glucose control in the first trimester?

A retrospective study of 133 pregnancies in women with Type 1 diabetes was performed, and the 116 which progressed beyond 28 weeks were further analysed. Despite good maternal blood glucose control (mean (+/- SE) HbA1 levels 8.6 +/- 0.2% at the end of the first trimester; 6.9 +/- 0.2% at delivery; normal range 4.0-8.5%), 38% of babies had birthweights above the 90th centile and operative intervention occurred in 77 deliveries (66%). There was no significant correlation between birthweight and HbA1 level at any stage of pregnancy, but mothers with babies above the 90th centile for weight had a higher HbA1 at the end of the first trimester than mothers with babies below the 90th centile (9.3 +/- 0.5 vs 7.9 +/- 0.2%, p less than 0.05). In contrast there was no difference in the HbA1 levels at delivery (7.0 +/- 0.3 vs 6.8 +/- 0.2%). The perinatal mortality rate was 17.7 per 1000 births. The results confirm that in Type 1 diabetes large babies are common despite good blood glucose control, and suggest that maternal blood glucose control in the first trimester may be an important determinant of birthweight.

Preconceptional nutrition

Preconceptional nutrition assessment and intervention is essential for optimal pregnancy outcome. Attainment of an appropriate prepregnancy weight is crucial to the success of a subsequent pregnancy. Metabolic stabilization of disease states or surgery induced imbalances are vital in any woman in which these problems occur. The effect of medications on nutrient status and use of nutrient supplements should be evaluated. Prior to conception women should be counseled to increase the nutrient density of their diet with special emphasis on iron, calcium, magnesium, zinc, folate, and vitamin B-6.

Unique brain anomalies in an infant of a diabetic mother

An offspring of a class F diabetic primigravida with marginal control during the first 8 weeks of the gestation had a level II sonogram at 23 weeks. It showed polyhydramnios and "hydrocephaly." Macrosomia, right hydroureter, megacystis and premature birth corroborated the diagnostic impression of diabetic embryopathy. At age 3 years, the child functions within the moderate range of mental retardation. Angiography, choanogram, CT and MRI scans showed unique CNS abnormalities that appeared secondary to a hamartomatous growth within the left cerebral hemisphere. Such anomaly, most likely a part of the phenotype of the diabetic embryopathy, implies a growth disturbance secondary to dysregulated paracrine growth factors (somatomedins, nerve growth factor, panregulin and/or their receptors in this case). It also indicates a possibility of interaction between two dysregulated major growth mechanisms; the endocrine in the mother considered responsible for the overall phenotype of the diabetic embryopathy/fetopathy and the paracrine fine tuning mechanism in the embryo incriminated by the hamartomatous over/undergrowth.

Thumb duplication and contralateral thumb hypoplasia in infant of mother with diabetes

Uncontrolled maternal diabetes frequently results in congenital anomalies. This report describes an infant of a mother with diabetes born with thumb hypoplasia and contralateral thumb duplication without other associated anomalies. Maternal diabetes should be part of the etiologic differential diagnosis of thumb anomalies. The concomitant occurrence of thumb duplication and hypoplasia, apparently as a result of the same systemic insult, suggests a close relationship between hypoplasia and duplication.

Can prepregnancy care of diabetic women reduce the risk of abnormal babies?

OBJECTIVE

To see whether a prepregnancy clinic for diabetic women can achieve tight glycaemic control in early pregnancy and so reduce the high incidence of major congenital malformation that occurs in the infants of these women.

DESIGN

An analysis of diabetic control in early pregnancy including a record of severe hypoglycaemic episodes in relation to the occurrence of major congenital malformation among the infants.

SETTING

A diabetic clinic and a combined diabetic and antenatal clinic of a teaching hospital.

PATIENTS

143 Insulin dependent women attending a prepregnancy clinic and 96 insulin dependent women managed over the same period who had not received specific prepregnancy care.

MAIN OUTCOME MEASURE

The incidence of major congenital malformation.

RESULTS

Compared with the women who were not given specific prepregnancy care the group who attended the prepregnancy clinic had a lower haemoglobin AI concentration in the first trimester (8.4% v 10.5%), a higher incidence of hypoglycaemia in early pregnancy (38/143 women v 8/96), and fewer infants with congenital abnormalities (2/143 v 10/96; relative risk among women not given specific prepregnancy care 7.4 (95% confidence interval 1.7 to 33.2].

CONCLUSION

Tight control of the maternal blood glucose concentration in the early weeks of pregnancy can be achieved by the prepregnancy clinic approach and is associated with a highly significant reduction in the risk of serious congenital abnormalities in the offspring. Hypoglycaemic episodes do not seem to lead to fetal malformation even when they occur during the period of organogenesis.

Embryopathic effects of short-term exposure to hypoglycemia in mouse embryos in vitro

The effect of short-term hypoglycemia was studied at two stages of development in postimplantation mouse embryos in vitro. Day 8 (gastrulating) mouse embryos were placed in hypoglycemic medium (60, 80, 100, or 110 mg/dl glucose) for 4 hours in which normoglycemia (120 to 150 mg/dl glucose) was restored for the remaining 44 hours of culture. Day 9 (neurulating) mouse embryos were exposed to hypoglycemia (20, 40, 60, or 80 mg/dl glucose) for 2, 4, 6, or 24 hours followed by normoglycemia for the remainder of 24 hours. At the end of culture embryos were evaluated for growth and malformations and compared with controls grown in normoglycemic medium. The results show that a 50% reduction in glucose for as little as 2 hours causes dysmorphogenesis in neurulating mouse embryos, whereas longer exposure times, more severe levels of hypoglycemia, or both are required to affect growth. Furthermore, gastrulating embryos are more sensitive to short periods of hypoglycemia than those undergoing neurulation.

GLUCOPAGE: a computer program for managing diabetic pregnancy

The microcomputer is an invaluable aid in the management of diabetes mellitus because of its ability to manipulate, summarise, and produce graphical displays from blood glucose data in such a way that new trends, or the effects of changes in therapy, are more readily apparent to the clinician. Currently available software however, while adequate for most purposes, has not been written to cope with the unique problems presented by diabetic pregnancy in which large amounts of data are generated over short periods of time, insulin requirements may change rapidly, and blood glucose control must be extremely tight. We have produced a new program, GLUCOPAGE, specifically for use in the management of diabetic pregnancy. GLUCOPAGE operates in conjunction with the Ames Memory Glucometer, from which it can download data either directly or telemetrically via a modern into the host IBM PC or compatible microcomputer. Large amounts of data can be summarised in various tabular and graphical formats on screen or in printed form. A single A4-size printout, the Glucopage, provides tabular and graphical summaries of a full week's blood glucose data. Copies of the Glucopage may conveniently be filed in the case notes, given to the patient or distributed to other medical staff.

Manifestation of diabetes mellitus on mouse follicular and pre-embryo development: effect of hyperglycemia per se

Animal models of diabetes mellitus during pregnancy have repeatedly suggested that maternal hyperglycemia was teratogenic during organogenesis, and thus may contribute to diabetic teratogenesis. However, little attention has been focused on the effects of hyperglycemia on pre-organogenic development. In this report, we examine the effect of hyperglycemia (950 mg glucose/dL) on the development of mouse pre-embryos in vitro. B6C3F1 mice were superovulated with 5 U pregnant mare serum gonadotropin (PMSG) followed by 5 U human chorionic gonadotropin (hCG) 48 hours later. Two cell pre-embryos were recovered 48 hours later, pooled together, and randomly assigned to different treatment groups. Cultures were performed in HAM's F-10 media (Gibco, Long Island, NY) with 0.1% bovine serum albumin (BSA; Sigma, St. Louis, MO) BSA at 37 degrees C in an atmosphere of 5% CO2, 5% O2, and 90% N2 with 15 to 30 embryos per milliliter of culture fluid. Cultures were viewed daily at 24, 48, and 72 hours after culturing, with recording of the development. Compared with control pre-embryos (n = 216), embryos cultured in elevated glucose levels (950 mg/dL) (n = 226) demonstrated marked growth retardation as assessed both by (1) distribution of developmental stages at each observation point (24 hours, P less than .001; 48 hours, P less than .006; 72 hours, P less than .001); and (2) a difference in the average rank sums indicating a delay in maturation (P less than .005). In a second protocol group, pre-embryos were cultured in an equivalent amount of L-glucose; no impairment in development compared with controls was noted.(ABSTRACT TRUNCATED AT 250 WORDS)

Advances in the management of diabetes mellitus

This article shall highlight several areas where recent developments have made, and may make in the future, practical advances to diabetes care. These advances have been in the areas of insulin therapy, glucose monitoring, identifying pre-diabetics and using immunosuppressive agents in pre-diabetes and early diabetes, pancreatic transplantation, and managing acute and chronic complications of diabetes.

Treatment of the embryo and the fetus in the first trimester: current status and future prospects

An effective treatment is now available to prevent the masculinization of female fetuses with congenital adrenal hyperplasia. Some vitamin-responsive inborn errors of metabolism can be treated prenatally by cofactor administration. Maternal phenylketonuria and maternal diabetes mellitus and the prevention of recurrent neural tube defects are also areas where therapeutic advances are being made. It may be possible to carry out chorionic villi sampling before 8 weeks menstrual age if appropriate catheters and guidance systems (probably transvaginal ultrasound) are used. First trimester diagnosis and treatment of fetal cardiac arrhythmias could prove to be very important, as they are later in pregnancy. Future possibilities for progress include gene microinjection into zygotes, classification and treatment of fresh embryos, biopsy and frozen storage of genetically at risk embryos, and therapy of preimplantation embryos by chimera formation or gene introduction by retroviruses.

Type 1 (insulin-dependent) diabetes mellitus diagnosed during pregnancy: a clinical and prognostic study

The study concerns the clinical outcome and later prognosis (regarding permanent insulin treatment) of patients who develop insulin-dependent diabetes mellitus during pregnancy (which is different from gestational diabetes). Sixty-three such patients (27 +/- 1 (SEM) years old) were delivered at the Copenhagen Centre for Diabetes and Pregnancy during the years 1966-1980. Obstetric complications such as toxaemia were seen in 9.5% of these study patients and the perinatal mortality was 6.3%, both percentages being higher than in the general population (1.1%, p less than 10(-7) and 1.0%, p less than 10(-3), respectively), but similar to those observed in patients with Type 1 diabetes diagnosed before pregnancy. In contrast, the frequency of malformations was 1.6%, the same as in the general population (1.4%), but lower than that seen in patients with long-standing diabetes (8.3%, p less than 0.05). At follow-up examination 8 +/- 1 years after diagnosis all patients were diabetic; 77% were insulin treated, having no or virtually no residual B-cell function, and were clearly Type 1 diabetic patients. After delivery 80% of the patients had a remission period (median 256 days) without insulin treatment. This remission period was absent or shortest in patients with the following characteristics (p less than or equal to 0.03): low age, first parity, not overweight, and high blood glucose level at diagnosis. These prognostic parameters should be considered in obligatory, clinical follow-up plans for such patients.

High glucose levels decrease proliferation of cultured human fetal cells from placenta

We used the placenta as a source of undifferentiated cells to study the effect high glucose levels can have on human fetal cell proliferation in vitro. Cells were subcultured in a modified minimum essential medium with 10% fetal bovine serum containing either 5.5 mmol/L (100 mg/dl) D-glucose (control), 11 mmol/L (200 mg/dl) D-glucose, or 22 mmol/L (400 mg/dl) D-glucose. Cells grown in mannitol-containing media were used as controls for osmolality. After 3 and 7 days' growth in different media, the labeling index was determined by autoradiographic analysis, and cell numbers were determined with a Coulter counter. The labeling indices for cells grown 3 days in 11 or 22 mmol/L D-glucose were 89% (p less than 0.002) and 84% (p less than 0.001), respectively, of control cells grown in 5.5 mmol/L D-glucose. After 7 days' growth, the labeling indices of cells grown in 11 or 22 mmol/L D-glucose were 84% (p less than 0.002) and 70% (p less than 0.001), respectively, of cells grown in 5.5 mmol/L D-glucose media. There was a significant decrease in the number of cells present at both 3 and 7 days in cultures grown in 22 mmol/L D-glucose compared with control. We conclude that a few day's exposure to high glucose levels can have an effect on proliferation of human placental cells in vitro. We suggest that a glucose effect on proliferation of other cells derived from the products of conception might be one mechanism contributing to abnormal development in some pregnancies of diabetic women.

Diabetes mellitus in pregnancy. Management and outcome of diabetic pregnancies in the state of Hesse, F.R.G.; a five-year-survey

From 1982 to 1986, data of 446 pregnancies in diabetic women were compared to equivalent information on 111,390 unselected non-diabetic pregnancies with the help of the Hessische Perinatalstudie (Hessian Perinatal Study, HEPS), a computerized system of collecting information on obstetrical care in the state of Hesse, F.R.G. Patient histories, pregnancy risks, birth risks, fetal outcome and maternal well-being were evaluated to survey the current situation of diabetic pregnancies in the specific constellation of widely decentralized obstetrical management and to point out possible benefits of stronger centralization of these high-risk pregnancies. Perinatal mortality in children of diabetic mothers (4.89%) remains substantially higher than in children of non-diabetic mothers (0.63%), with two thirds of the fetal loss occurring before birth. Infant morbidity, including macrosomia, shows the same impact of maternal diabetes. Maternal post-partum morbidity is increased in diabetic women. 37.9% of children of diabetic mothers were delivered in obstetrical units equipped for maximal care, 17.5% in primary care level hospitals. Perinatal mortality and morbidity as well as maternal complications indicate that diabetic women should receive obstetrical care in those centers that can provide all the necessary facilities.

Fuel-mediated teratogenesis: biochemical effects of hypoglycemia during neurulation in mouse embryos in vitro

Hypoglycemia has been reported to induce congenital malformations and growth retardation in rodent embryos during the period of neural tube closure in vitro. However, the biochemical alterations responsible for the production of the dysmorphogenic effects have not been evaluated. Therefore, the rates of glucose metabolism by glycolysis, citric acid cycle, oxidative pentose phosphate pathway (PPP), and anabolic utilization were evaluated in mouse embryos and extraembryonic membranes using the whole embryo culture technique. Altered glucose metabolism by glycolysis and oxidative PPP, as well as altered anabolic synthesis, were produced by exposure to hypoglycemia. In embryos exposed to mild hypoglycemia (80 mg/dl) altered metabolism by the PPP and an associated effect on nucleic acid synthesis were in part responsible for the dysmorphogenic effects of this treatment. In contrast, severe hypoglycemia (40 mg/dl) appeared to have an immediate effect on glycolytic metabolism in addition to effects on the PPP and nucleic acid synthesis. Therefore, a multifactorial biochemical mechanism contributes to the induction of malformations by severe hypoglycemia in mouse embryos in vitro. Furthermore, the differential effects of moderate vs. severe hypoglycemia on glycolytic metabolism, and possibly energy production, may account for the differences in the severity of these treatments on embryonic growth and the incidence of malformations.

Oestrogen and progestogen receptors in endometrium and myometrium at the time of blastocyst implantation in pregnant diabetic rats

A suitable hormonal environment is a prerequisite for blastocyst implantation. Experimental diabetes was previously shown to modify the hormonal milieu and produce alterations in oestrogen receptor kinetics in the uterine tissue. In the present work, oestrogen and progestogen receptor levels were measured on the morning of day 6 of pregnancy in normal and in streptozotocin-induced diabetic rats, both in implantation sites and in interembryonic segments of endometrium and myometrium. Receptor levels were different in the implantation sites compared to the interembryonic segments of endometrium, both in the control and in the diabetic animals. Indeed, implantation sites were characterized by lower oestrogen receptor levels in cytosol and higher progestogen receptor levels in cytosol and nuclei. However, compared to the control rats, the diabetic rats had lower oestrogen receptor levels in implantation sites, both in cytosol and nuclei. In the myometrium, the differences between sites or between types of rats were minimal. Plasma levels of oestradiol were lower in diabetic rats than in control animals, whereas progesterone levels were similar. A 20% lower implantation rate was found in diabetic rats, compared to normal rats. These results show that the specific distribution of oestrogen and progestogen receptors between implantation sites and interembryonic segments was preserved in the diabetic rats; however the absolute level of oestrogen receptor was lower. This abnormal endocrine milieu might arise from a lower oestradiol level and a decreased oestradiol/progesterone ratio in the circulating blood. Whether the lower implantation rate in diabetic rats might be a consequence of the overall disturbed hormonal status remains to be elucidated.

Prematurity among insulin-requiring diabetic gravid women

From Jan. 1, 1983, through Dec. 31, 1987, 420 gravidas with insulin-requiring diabetes antedating pregnancy delivered on the Joslin Clinic service. Among them, 110 pregnancies (26.2% of the total) delivered before 37 completed weeks of gestation compared with a 9.7% incidence (906/9368) for the general population at the Brigham and Women's Hospital during calendar year 1985. Thirty-three percent of all premature deliveries were the result of the development of preeclampsia. The relative risk of prematurity for diabetic patients with any hypertensive complication was 2.0 (95% confidence interval, 1.40 to 2.87) compared with normotensive diabetic subjects. Compared with the general population, most of the excess risk of prematurity was confined to hypertensive diabetics and normotensive patients of more advanced White class. A history of having had a previous premature delivery, increasing duration of diabetes antedating pregnancy, and carrying a male fetus in the index pregnancy were significantly associated with premature delivery. Future efforts to reduce the incidence of prematurity among diabetic gravidas should be directed toward reducing the incidence of preeclampsia.

Effects of human diabetic serum on the in vitro development of mouse preimplantation embryos

The effects of sera from different types of human diabetes (type I with and without ketoacidosis; type II treated with insulin or Daonil or untreated) on the in vitro development of early preimplantation mouse embryos were studied. In controls, 20% of blastocysts failed to develop successfully when grown for 72 h in RPMI medium supplemented with 10% fetal bovine serum and 50% nondiabetic human serum. In experiments using 50% diabetic serum, the highest embryotoxic effect was found in type-I diabetes with and without ketoacidosis: The percents of undeveloped embryos were 66 and 58, respectively. In type-II diabetes, embryotoxic effects were found among all studied types: The percent of undeveloped blastocysts varied from 36% in insulin-treated type-II diabetes to 44% in untreated type-II diabetes. A high correlation was found between the number of undeveloped embryos and the blood concentrations of metabolic diabetic factors: glucose (r = .53-.64 in type-I diabetes), B-HOB (r = .7-.77 in type-II diabetes untreated or treated with Daonil), acetoacetate (r = .66 in insulin-treated type-II diabetes), and HbA1c (r = .89 in insulin-treated type-II diabetes or .99 in Daonil-treated type-II diabetes). A concentration of 80% serum was embryo-toxic when obtained from nondiabetic or from diabetic human. The possible role of diabetic metabolic factors in causing increased risk of spontaneous abortions and infertility among diabetic women is discussed.

Diabetes and pregnancy

Prior to the introduction of insulin, a vast majority of pregnancies complicated by diabetes ended in perinatal death, with an associated risk of maternal death. Currently, virtually all diabetic women can undergo pregnancy with the expectation of good maternal and fetal outcome. However, many challenges still remain in preventing congenital anomalies and macrosomia.

Maternal milk and plasma glucose and insulin levels: studies in normal and diabetic subjects

The relationship between maternal glucose levels and the concentration of glucose and insulin levels in human milk from diabetic women has not been elucidated. In addition, the rate of appearance of intravenously injected insulin to the change in concentration of insulin in maternal milk has not been studied. To study this relationship of glucose levels in serum to glucose levels in milk, maternal milk and glucose levels were measured in diabetic lactating women (n = 7) and nondiabetic lactating women (n = 10). In addition, the change in milk concentration of insulin was studied after an intravenous injection of insulin. The maternal whole blood glucose in the seven diabetic women was stabilized at a baseline blood glucose of approximately 100 mg/dl and then elevated with an infusion of intravenous glucose to a level of three times baseline (approximately 300 mg/dl for up to 2 hours). The plasma glucose was then lowered back to baseline with intravenous insulin over 20 minutes. The baseline serum insulin and glucose levels were compared to nonlactating women who donated serum to measure insulin levels in normal controls. Maternal milk glucose levels rise following an increase of plasma glucose levels with a lag time to the peak glucose level of 40-90 minutes, and return to baseline following the return of plasma glucose to baseline with a lag time of 120-150 minutes. Baseline milk insulin levels are elevated in hyperinsulinemic women and the levels of insulin in the milk will rise dramatically above baseline values after an intravenous injection of insulin with a lag time to the peak of concentration in milk of 60-80 minutes.(ABSTRACT TRUNCATED AT 250 WORDS)

First-trimester hemoglobin A1 and risk for major malformation and spontaneous abortion in diabetic pregnancy

The relationship between the level of hemoglobin A1 (Hb A1) in the first trimester and major malformations and spontaneous abortions was examined in 303 insulin-requiring diabetic gravidas. During the study period, all patients with insulin-requiring diabetes mellitus antedating pregnancy who registered for prenatal care prior to 12 weeks' gestation and who had a known outcome were included. Thirty-five percent of the patients entered with a first-trimester Hb A1 of greater than 11.0% of total hemoglobin (9 standard deviations above the mean for a nondiabetic population). A broad spectrum of glycemic control was therefore represented. The risk of spontaneous abortion was 12.4% with first-trimester Hb A1 less than or equal to 9.3% and 37.5% with Hb A1 greater than 14.4% (risk ratio 3.0; 95% confidence interval 1.3-7.0). The risk for major malformation was 3.0% with Hb A1 less than or equal to 9.3% and 40% with Hb A1 greater than 14.4% (risk ratio 13.2; 95% confidence interval 4.3-40.4). Although the risks for both adverse outcomes were markedly elevated following a first trimester in very poor metabolic control, there was a broad range of control over which the risks were not substantially elevated. To keep malformations and spontaneous abortions to a minimum among diabetic women does not require "excellent" control; there seems to be a fairly broad range of "acceptable" control.

Ultrasonographic assessment of early fetal growth in insulin-treated diabetic pregnancies

Early fetal growth aberrations have been suggested in diabetic gestations. To characterize such aberrations sonographically, longitudinal crown-rump length measurements were made in a group of 20 control and 20 diabetic pregnancies. The study evaluated growth between 40 and 100 days of amenorrhea. The best-fit curve of growth as a function of gestational age was that of a nonlinear polynomial regression curve for both the control and the diabetic groups. The correlation coefficients were 0.997 and 0.887 for the control and diabetic groups, respectively; the standard error of the estimate was 0.054 and 0.19, respectively. A log10 linear transformation was performed successfully on each curve. Comparison of the slopes and the intercepts of the transformed control and diabetic curves revealed no significant differences. To evaluate the possibility of a transient fetal growth delay, interval growths and interval growth velocities were compared between groups. No significant differences were observed. The control and diabetic groups' mean (+/- SD) growth velocities were 0.043 +/- 0.023 and 0.040 +/- 0.022 mm/day/mm total, respectively (p = NS). The growth of two anomalous fetuses in the diabetic group was studied individually. Their growth characteristics could not be distinguished from the control fetuses' growth profiles. The present study fails to confirm the presence of early fetal growth delay in diabetic pregnancies. Moreover, the data suggest that the fetuses' early growth in the mother with poorly controlled diabetes is similar to that of control fetuses.

Diabetes and pregnancy

Despite improvement in perinatal outcome over the past several decades, controversy still exists regarding both the management and pathophysiology of pregnancy complicated by diabetes mellitus. In this article, potential factors contributing to morbidity observed in the offspring of diabetic women are considered. The clinical management of insulin-dependent and gestational diabetes is also discussed.

Modern management of insulin-dependent diabetes mellitus

Currently available treatment methods, albeit improved, remain less than totally satisfactory. New developments such as improved viability of whole organ pancreatic transplants, islet cell transplantation, immunosuppression in the treatment of new-onset diabetes, development of reliable glucose sensors to provide continuous feedback for insulin delivery devices, and alternate routes for insulin administration may drastically change diabetes treatment in the future. For now, physicians must carefully consider the risks and benefits associated with available treatments when discussing therapeutic options with patients and their families. The wide range of therapies available provides the opportunity for patient and physician to select the most appropriate treatment regimen.

Diabetes in pregnancy: maternal and infant outcome

Previous studies have shown that diabetic women more commonly have complications of pregnancy and adverse infant outcomes than do other women. However, most of the studies have not evaluated women with gestational diabetes separately. The purpose of this study was to evaluate pregnancy complications and infant morbidity and mortality among births to women with gestational diabetes and women with established diabetes. Birth certificate data from 1984 in Washington State linked with death certificate data provided information on complications of pregnancy and infant outcome for 422 gestational diabetics and 144 established diabetics. A comparison group of 856 non-diabetic women who delivered a child was selected at random. Both established and gestational diabetic women were more likely to be reported to develop pre-eclampsia (relative risk (RR) = 4.0 and 9.6). Established and gestational diabetic women were also at increased risk of delivery by Caesarean section (RR = 2.1 and 5.0). Infants of established diabetics had a higher risk of congenital anomalies (RR = 7.6) than infants of non-diabetics and were at increased risk of death in the first 4 weeks (RR = 7.9) and the first year of life (RR = 5.0). Gestational diabetics were more likely to have high birthweight babies (greater than 4000 g) (RR = 2.1) while established diabetics were more likely to have babies at either extreme of birthweight (greater than 4000 g, RR = 1.7; less than 2500 g, RR = 3.2). We conclude that both gestational and established diabetes are associated with important increases in risk of pregnancy complications and adverse infant outcomes.

Does the severity of diabetic retinopathy predict pregnancy outcome?

The authors sought to determine whether the severity of diabetic retinopathy is a predictor of subsequent pregnancy outcome. One hundred and seventy-nine pregnant diabetic women were evaluated in their first trimester of pregnancy. Stereoscopic color photographs of the ocular fundus were taken and graded by the Fundus Photography Reading Center. Thirty-nine women had no retinopathy, while 28 had proliferative retinopathy in the worse eye. The women's history and hospital delivery room charts were reviewed with regard to pregnancy outcome. Thirty-three pregnancies terminated with an adverse outcome. A logistic regression analysis was used to evaluate significant predictors of pregnancy outcome. Of maternal age, duration of diabetes, glycosylated hemoglobin, proteinuria, cigarette smoking status, and severity of diabetic retinopathy, only the last variable significantly predicted an adverse outcome. These data suggest that the severity of retinopathy should be considered when counseling a pregnant diabetic woman.

Non-enzymatic glycation of fetal tissue in diabetic pregnancy. Estimation of the glucitollysine content of umbilical cord extracts

Non-enzymatic glycation of fetal tissue was studied by determining the glucitollysine content of umbilical cord extracts from twelve infants of diabetic mothers and fourteen infants of healthy, non-diabetic women (controls). The single, glycated amino-acid glycitollysine, which reflects the extent of glycation processes in biological samples, was measured by a standard amino acid ion exchange chromatography followed by reverse phase high pressure liquid chromatography. Infants of diabetic mothers had significantly higher cord glucitollysine levels than infants of control mothers (14.3 + 4.6 vs. 5.5 + 2.1 ng/mg dry tissue; M + SD, p less than 0.001). Moreover, five infants of diabetic mothers with congenital anomalies had strikingly high glucitollysine levels, higher than the mean +4 SD of the controls. We conclude, that non-enzymatic glycation of fetal tissue does occur as a result of an in utero exposure to cumulative glycemia. Major congenital anomalies in diabetic pregnancies are associated with a greater extent of non-enzymatic glycation of umbilical cord tissue.

Prospective study of an inverse relationship between maternal glycosylated hemoglobin and serum alpha-fetoprotein concentrations in pregnant women with diabetes

A hypothesized inverse relationship between the concentration of glycosylated hemoglobin and serum alpha-fetoprotein was observed in a prospective study of 39 pregnant women with insulin-dependent diabetes as well as seven pregnant women with diabetes who did not require insulin (r = -0.434, p less than 0.002). No similar correlation was found among a selected population of healthy pregnant women (r = -0.129). Because the level of glycosylated hemoglobin in pregnancy correlates with poor outcome, including the occurrence of fetal anomaly, it may be important to quantify glycosylated hemoglobin in pregnancies with low alpha-fetoprotein levels. These results also suggest that the maternal concentration of glycosylated hemoglobin can be used to adjust serum alpha-fetoprotein values before their interpretation in the screening of pregnant women with diabetes.

Lack of relation of increased malformation rates in infants of diabetic mothers to glycemic control during organogenesis

To determine how much insulin-dependent diabetes increases a woman's risk of giving birth to a malformed infant and how that risk is influenced by metabolic control, we followed 347 diabetic and 389 control women who enrolled in the study within 21 days of conception (the early-entry group) and 279 diabetic women who entered later (the late-entry group). We detected major malformations in the infants of 4.9 percent of the early-entry diabetic women, 2.1 percent of the controls, and 9.0 percent of the late-entry diabetic women. Malformation rates were significantly higher among offspring of early-entry diabetic women than among those of controls (odds ratio, 2.45; lower one-sided 95 percent confidence limit, 1.12; P = 0.027), and higher among late-entry than among early-entry diabetic women (odds ratio, 1.91; lower one-sided 95 percent confidence limit, 1.07; P = 0.032). Mean blood glucose and glycosylated hemoglobin levels during organogenesis were not significantly higher in women whose infants were malformed. Hypoglycemia (glucose, less than or equal to 50 mg per deciliter [2.8 mmol per liter]) was not significantly more common in the same group. Hyperglycemia and glycosylated hemoglobin were not correlated with malformation. The data suggest that more sensitive measures are needed to identify the teratogenic mechanisms, or that not all malformation can be prevented by good glycemic control. Despite the increased malformation rate among infants of the early-entry diabetic women, as compared with the controls, the more favorable outcome seen in the former group as compared with the late-entry group justifies the attempt to achieve good metabolic control around the time of conception.

The influence of maternal glucose metabolism on fetal growth, development and morbidity in 917 singleton pregnancies in nondiabetic women

To study the effects on the fetus of variations in maternal glucose tolerance, a 25 g rapid intravenous glucose tolerance test was performed at or about 32 weeks gestation in 917 randomly selected nondiabetic women with singleton pregnancies. The results were withheld from the patients and their obstetricians and paediatricians, and no treatment or advice was offered. Fasting plasma glucose and indices of glucose disposal (including a new index which we have termed "summed glucose") were distributed unimodally, with no evidence of a separate pathological group towards the diabetic end of the distributions. Significant associations were found between maternal glucose metabolism and various measures of neonatal nutrition and morbidity, including the incidence of congenital malformations and morbidity related to asphyxia, suggesting that variations within the normal range in maternal glucose metabolism can influence growth and development in the fetus. These relationships were continuous throughout the range of maternal glucose tolerance and were not of predictive value in individual cases.

Development of rat embryos cultured in serum prepared from rats with streptozotocin-induced diabetes

The effects of 40, 50, and 60 mg/kg streptozotocin (SZ) on the body weights and the glucose concentration and the osmolarity of the serum of adult rats were determined. Serum prepared from these SZ-dosed rats was used in embryo culture experiments to investigate effects of diabetic serum on rat embryos during organogenesis. The diabetic serum resulting from each of the tested doses of SZ was teratogenic to 9.5-day rat explants (embryos and their membranes), causing a range of dysmorphic lesions including craniofacial defects, heart defects, and abnormalities of the branchial arches and the otic capsules. Explants cultured in serum prepared from rats dosed with 60 mg/kg SZ also showed abnormal morphology of both the visceral yolk sac and the embryonic blood cells in the yolk sac capillaries. The development of explants repeatedly transferred between control and diabetic serum indicated that the severity of the dysmorphic effect was dependent on the duration of exposure to diabetic serum. The alternation of sera did not in itself appear to be damaging to the embryos. Explants cultured in control serum, control serum with its glucose concentration increased to that of the diabetic serum, or diabetic serum all took up the same amount of glucose from their culture medium; 30% of the embryos from the diabetic serum were abnormal compared to only 4% from the control serum and the control serum plus glucose.

Computerized and telemetric management of diabetic pregnancy in Cambridge

In order to optimize the quality of our care, we have used the Ames Memory Glucometer in our computerized management of 17 insulin-dependent diabetic pregnancies. Patients measured their own blood glucose levels on 4.5 +/- 1.2 (SD) occasions per day, and six of them transmitted their blood glucose measurements telemetrically from home into a hospital-based computer on a total of 42 occasions. We achieved near-optimal blood glucose levels and normal HbA1 levels throughout most of these 17 pregnancies. Average blood glucose levels were 6.4 +/- 0.9 mmol/l in the first, 5.9 +/- 1.2 mmol/l in the second, 5.4 +/- 1.0 mmol/l in the third trimester. Corresponding values for HbA1 were 8.0 +/- 1.5%, 6.5 +/- 0.8%, and 6.2 +/- 0.4%. Average insulin requirement doubled during pregnancy, but fell to 74% of the pre-pregnancy dosage by one week after delivery. The average gestational age at delivery was 38.9 +/- 1.3 weeks, and we had no perinatal deaths. Two of the babies were macrosomic, even though their mothers had good diabetic control. Four patients were delivered by Caesarean section. However we achieved a vaginal delivery in 93% of those in whom it was planned. Our computerized system of managing diabetic pregnancies was efficient, safe, and popular with our patients.

Managing diabetic patients with nephropathy and other vascular complications

Since the metabolic changes in normal pregnancy are diabetogenic, pregnancy imposes a severe stress on the metabolic milieu of diabetic patients. Moreover, many patients with long-standing diabetes have vascular complications, including retinopathy, renal insufficiency, nephrotic syndrome and hypertension, that represent separate risk factors for optimal fetal development. Recent experience has suggested that maternal hyperglycaemia, and associated fetal hyperinsulinaemia, may represent an important factor in the development of fetal complications. During the past two to three decades the incidence of perinatal deaths has been reduced in all cases of diabetics to a level that approaches the rate in healthy gravidas when severe congenital anomalies are excluded. Fetal and neonatal morbidity have also been reduced, although rates of congenital anomalies, polyhydramnios and respiratory distress syndrome remain high. In patients with significant vascular complications, especially nephropathy and retinopathy, there is no evidence that pregnancy alters the natural course of these complications. Although the morbidity associated with oedema formation and hypertension is elevated, with meticulous management of patients with diabetic nephropathy, especially in the absence of severe renal insufficiency and/or severe hypertension, pregnancy performance and outcome can be similar to other insulin-dependent diabetics.

Effects of hypoglycaemia on early embryogenesis in rat embryo organ culture

As congenital malformations may be caused by perturbations of glycolytic flux on early embryogenesis [16], effects of hypoglycaemia were investigated by using rat embryo organ culture. Nine and one-half day old rat embryos were grown in vitro for 48 h (day 9 1/2 to 11 1/2) in the presence of hypoglycaemic serum for different hours during the culture period. Hypoglycaemic serum was obtained from rats given insulin intraperitoneally. On exposure to hypoglycaemic serum during the first 24 h of culture (day 9 1/2 to 10 1/2), embryos showed marked growth retardation and had increased frequencies of neural lesions (42.7% versus 0%, p less than 0.01), in contrast to hypoglycaemic exposure during the second 24 h of culture (day 10 1/2 to 11 1/2), where only minor growth retardation and low frequencies of neural lesions (2.4% versus 0%, NS) were seen. Even exposure to hypoglycaemic serum for a relatively short period (8 h) during the first 24 h of culture resulted in neural lesions at the frequency of 9.3-13.3%. The embryos exposed to hypoglycaemia demonstrated decreased glucose uptake and lactic acid formation, indicating decreased energy production via glycolysis that constitutes the principal energy pathway at this stage of embryonic development. These results suggest that hypoglycaemia during critical periods of embryogenesis has adverse effects on the development of the embryo and these effects might be mediated through metabolic interruption of embryogenesis.