Fetal acidosis and hyperlacticaemia diagnosed by cordocentesis in pregnancies complicated by maternal diabetes mellitus

Multidisciplinary Workup for Stillbirth at a Tertiary-Care Hospital in Northeast Mexico: Findings, Challenges and Perspectives

OBJECTIVES

Stillbirth is an important health problem, and in Mexico, only half of the stillbirths have an explainable cause. The aim of this study was to implement a multidisciplinary workup to identify the etiology and potential risk factors for stillbirth at the Hospital Universitario "Dr. José Eleuterio González".

METHODS

This is a prospective, descriptive, observational study that included stillbirths from the Obstetrics Service from October 1st, 2019 to May 25, 2020. Evaluation strategies included a complete maternal medical history, physical examination of the fetus, and a photographic medical record. For every stillbirth either a prenatal ultrasound, a postnatal x-ray, or a fetal autopsy, were needed. Multiplex Ligation Probe Amplification (MLPA) was performed with an umbilical cord sample.

RESULTS

Thirty-three stillbirths were reported; 21 were included in the analysis. Eleven women (52.3%) had known risk factors for stillbirth, mainly elevated body mass index and diabetes. On physical examination, external birth defects were found in 8 fetuses (38%). X-ray was performed in 14 cases (66%), alterations were detected as a probable etiologic cause just in one. All cases underwent MLPA, which were reported negative. Three cases had criteria for autopsy. Findings were inconclusive to determine etiology.

CONCLUSIONS

The best tools for evaluation of stillbirth were the elaboration of clinical history, physical examination, and prenatal ultrasound. Diabetes and obesity were the most frequent risk factors found in our population. These factors are preventable by implementing strategies that lead to better prenatal care.

A proposed fetal risk scoring system for gestational diabetes to assist in optimising timing of delivery

Background. The pathophysiology of gestational diabetes, which is related to abnormal gluocose tolerance and hyperinsulinaemia, renders standard fetal monitoring models ineffective, insufficient and inappropriate, as these models revolve around detecting and prognosticating on placenta-mediated disease rather than increased metabolic rates due to hyperinsulinaemia, functional hypoxia and ischaemic trophoblastic thresholds. To improve perinatal morbidity and mortality in gestational diabetes, there is therefore a need to introduce new prognostic parameters and scoring systems. Objectives. A proposed risk scoring system has been developed, based on our previous studies, to risk-categorise patients with gestational diabetes in terms of fetal outcome in view of the fact that the pathophysiology of gestational diabetes is not recognised by standard monitoring models, which revolve around placental insufficiency rather than metabolic anomalies.Methods. Patients with diabetes from four case-control studies were combined to form a total sample of 159 cases for validation of the risk scoring system. Univariate logistic regression analysis was used to assess the effect of individual risk factors with proposed cut-offs on adverse pregnancy outcome. The diagnostic accuracy of the total summative score was assessed by computing the area under the receiver operating characteristic (ROC) curve. Results. Four potential parameters were identified to risk-categorise fetuses in a pregnancy complicated by gestational diabetes, i.e. the myocardial performance index (MPI), the E/A ratio (early diastolic filling/late diastolic filling, a marker of diastolic dysfunction), increasing fetal weight (macrosomia), and an increased amniotic fluid index. The total score, obtained by summation of the composite scores for these parameters, ranged from 0 to 11. The total score performed as an excellent predictor of adverse outcome, evidenced by an ROC area under the curve of 0.94. A cut-point of 6 on the score confers a sensitivity of 84.2% and specificity of 90.2% for predicting adverse outcome. Conclusion. To our knowledge, this is the first gestational diabetes scoring system proposed to predict an adverse outcome.

Fetoplacental oxygen homeostasis in pregnancies with maternal diabetes mellitus and obesity

Despite improvements in clinical management, pregnancies complicated by pre-existing diabetes mellitus, gestational diabetes mellitus or obesity carry substantial risks for parent and offspring. Some of the endocrine and metabolic changes in parent and fetus in diabetes mellitus and obesity lead to fetal oxygen deficit, mostly due to insulin-induced accelerated fetal metabolism. The human fetus deals with reduced oxygenation through a wide range of adaptive responses that act at various levels in the placenta as well as the fetus. These responses ensure adequate oxygen delivery to the fetus, increase the oxygen transport capacity of fetal blood and redistribute oxygen-rich blood to vital organs such as the brain and heart. The liver has a central role in adapting to reduced oxygenation by increasing its oxygen extraction and stimulating erythropoietin synthesis to increase haematocrit. The type of adaptive response depends on the onset and duration of hypoxia and the severity of the metabolic disturbance. In pregnancies characterized by diabetes mellitus or obesity, these adaptive systems come under additional strain owing to the increased maternal supply of glucose and resultant fetal hyperinsulinaemia, both of which stimulate oxidative metabolism. In the rare situation that the adaptive responses are overwhelmed, stillbirth can ensue.

Evaluation of Fetal Cardiac Geometry and Contractility in Gestational Diabetes Mellitus by Two-Dimensional Speckle-Tracking Technology

Background: The most commonly known cardiac effect of gestational diabetes mellitus (GD) in the fetus is hypertrophic cardiomyopathy, but recent studies show that it is preceded by subclinical cardiac dysfunction. This study aimed to assess the effect of GD on fetal cardiac geometry and contractility by two-dimensional speckle-tracking technology. Methods: We performed a prospective observational study that included 33 pregnant patients with GD and 30 healthy individuals. For all fetuses, a four-chamber 3 s cine-loop was recorded and analyzed with Fetal Heart Quantification (FetalHQ®), a novel proprietary speckle-tracking software. The following cardiac indices were calculated: global sphericity index (GSI), global longitudinal strain (GLS), fractional area change (FAC), and 24-segment end-diastolic diameter (EDD), fractional shortening (FS), and sphericity index (SI) for both ventricles. Demographic and cardiac differences between the two groups were analyzed, as well as intra-rater and inter-rater reliability. Results: There were significant changes in right ventricular FAC and FS for segments 4−24 in fetuses exposed to GD (−1 SD, p < 0.05). No significant differences were detected for GSI, GLS, EDD, or SI for either ventricle. Conclusions: Fetuses exposed to GD present impaired right ventricular contractility, especially in the mid and apical segments.

Effect of later cord clamping on umbilical cord blood gas in term neonates of diabetic mothers: a randomized clinical trial

Objective

To evaluate the effect of later cord clamping (LCC) on umbilical arterial blood gas in neonates of diabetic mothers.

Methods

This prospective study included a group of 160 diabetic mothers (DM) whose neonates were randomized to immediate cord clamping (ICC) (≤ 15 s after birth) or LCC (≥ 30 s after birth), and a group of 208 non-diabetic mothers (NDM) whose neonates were randomized to ICC or LCC as a reference. Cord arterial pH, base excess (BE), bicarbonate (HCO₃⁻), partial pressure of carbon dioxide (pCO₂), partial pressure of oxygen (pO₂), lactate, hemoglobin, hematocrit and glucose were compared among groups.

Results

In neonates of DM, there was no significant difference in cord arterial pH between the ICC and LCC group. LCC of ≥ 30 s decreased umbilical arterial HCO₃⁻ and BE and increased lactate (ICC versus LCC, HCO₃⁻: 24.3 (22.7, 25.8) versus 23.7 (22.3, 24.7) mmol/L, P = 0.01; BE: -2.70 (-4.80, -1.50) versus − 3.72 (-5.66, -2.36) mmol/L, P = 0.006; lactate: 2.1 (1.6, 3.7) versus 2.7 (2.1, 4.3) mmol/L, P = 0.005), without the alterations of pCO₂, pO₂, hemoglobin, hematocrit and glucose. Similar results were found in neonates of NDM (ICC versus LCC, HCO₃⁻: 24.3 (23.1, 25.7) versus 23.5 (22.3, 24.8) mmol/L, P = 0.01; BE: -2.39 (-3.73, -1.51) versus − 3.40 (-4.73, -1.91) mmol/L, P = 0.001; lactate: 2.2 (1.9, 3.3) versus 2.5 (2.0, 4.3) mmol/L, P = 0.01), except for the higher level of hemoglobin in the LCC group. The majority of diabetic mothers (ICC: 92.0%; LCC: 91.8%) had good blood glucose control. No differences were observed in acid-base status and glucose between neonates of DM and neonates of NDM in both ICC and LCC, but hemoglobin and hematocrit were elevated after ICC in neonates of DM compared to neonates of NDM.

Conclusions

Later cord clamping of ≥ 30 s resulted in a tendency towards metabolic acidosis of umbilical arterial blood in neonates of DM and NDM. Umbilical arterial blood gas parameters at birth were similar in neonates of DM and NDM.

Trial registration

ClinicalTrials.gov: NCT04369313; date of registration: 30/04/2020 (retrospectively registered).

Diabetes during Pregnancy: A Maternal Disease Complicating the Course of Pregnancy with Long-Term Deleterious Effects on the Offspring. A Clinical Review

In spite of the huge progress in the treatment of diabetes mellitus, we are still in the situation that both pregestational (PGDM) and gestational diabetes (GDM) impose an additional risk to the embryo, fetus, and course of pregnancy. PGDM may increase the rate of congenital malformations, especially cardiac, nervous system, musculoskeletal system, and limbs. PGDM may interfere with fetal growth, often causing macrosomia, but in the presence of severe maternal complications, especially nephropathy, it may inhibit fetal growth. PGDM may also induce a variety of perinatal complications such as stillbirth and perinatal death, cardiomyopathy, respiratory morbidity, and perinatal asphyxia. GDM that generally develops in the second half of pregnancy induces similar but generally less severe complications. Their severity is higher with earlier onset of GDM and inversely correlated with the degree of glycemic control. Early initiation of GDM might even cause some increase in the rate of congenital malformations. Both PGDM and GDM may cause various motor and behavioral neurodevelopmental problems, including an increased incidence of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Most complications are reduced in incidence and severity with the improvement in diabetic control. Mechanisms of diabetic-induced damage in pregnancy are related to maternal and fetal hyperglycemia, enhanced oxidative stress, epigenetic changes, and other, less defined, pathogenic mechanisms.

Cardiac Doppler in poorly controlled gestational diabetics and its link to markers of intra-uterine hypoxia and adverse outcome

The aim of the study was to investigate foetal cardiac function using the modified myocardial performance index (Mod-MPI) in poorly controlled gestational diabetics and its link with intrauterine markers for hypoxia and to an adverse outcome. In a prospective, cross sectional study, 44 consecutive women with severe or poorly controlled gestational diabetic pregnancies in their third trimester on insulin therapy were recruited and matched with 44 women with normal pregnancies which served as the control group. Using Doppler echocardiography the foetal Mod-MPI was calculated. The foetal Mod-MPI was significantly higher in the diabetic group compared to the controls indicating significant myocardial dysfunction. The Mod-MPI served as an excellent marker of adverse outcomes. Foetal myocardial function was significantly impaired in poorly controlled gestational diabetics and there was a significant link of Mod-MPI to intrauterine markers of hypoxia, as well as to an adverse outcome. Mod-MPI has the potential to improve foetal surveillance in gestational diabetes.IMPACT STATEMENTWhat is already known on this subject? Abnormal foetal cardiac function, as reflected in the modified myocardial performance index, has been reported to be significantly increased in foetuses of poorly controlled diabetics managed on insulin.What do the results of this study add? There is a significant link between abnormal foetal cardiac function to intrauterine markers of hypoxia, as well as to an adverse outcome; and that development of myocardial dysfunction could be one of the main mechanisms, inducing foetal compromise in poorly controlled gestational diabetes.What are the implications of these findings for clinical practice and/or further research? This study explores an interesting concept of foetal pathophysiology in gestational diabetes, namely the concept of "pseudo-hypoxia" in a foetus of a gestational diabetic mother, and this intrauterine "hypoxic stress" in turn leading to myocardial dysfunction. The Mod-MPI, a clinical marker for cardiac dysfunction, can therefore be used in the clinical setting to track a deteriorating metabolic state.

Assessment of the Fetal Myocardial Performance Index in Well-Controlled Gestational Diabetics and to Determine Whether It Is Predictive of Adverse Perinatal Outcome

This study was aimed at determining if the myocardial performance index (MPI) is altered in well-controlled gestational diabetics and if so whether it is predictive of adverse perinatal outcome. In a prospective cross-sectional study, 54 consecutive women with well-controlled gestational diabetes controlled on insulin or metformin in the third trimester were recruited and matched with 54 women with normal pregnancies (control group). Using Doppler echocardiography, the MPI was calculated. Sonographic biophysical and placental resistance Doppler markers in both groups were also determined. An abnormal outcome was defined as any of the following: stillbirth; neonatal death; neonatal intensive care admissions; tachypnea with pulmonary edema; neonatal cord pH < 7.15; 5-min Apgar score < 7, polycythemia; and nucleated red blood cells > 10/100 white blood cell counts, hypoglycemia. The MPI was significantly higher in the diabetic group compared to controls (p < 0.0001). Rate of adverse outcome was 22% in the diabetic group. The diabetic group with adverse outcomes had significantly elevated MPI values compared to the diabetic group with normal outcomes. There were 26 diabetics controlled on metformin and 28 controlled on insulin. The adverse outcome rate was slightly higher in the IDDM group compared to the non-insulin-dependent group but was not statistically significant. The main adverse outcomes were low Apgars (18%), hypoglycemia (22%), polycythemia (13%) and low pH in 7%. All control births had normal outcomes. MPI served as an independent predictor of adverse outcome. The MPI z-score had a good diagnostic accuracy as evidenced by the area under the ROC curve of 0.83. An MPI z-score exceeding 4.55 conferred a 90% sensitivity and 74% specificity, with 77% of outcomes correctly classified with a likelihood ratio of 3.5. The MPI is impaired in fetuses in well-controlled gestational diabetes, with fetuses with an adverse outcome having significantly higher MPI values compared to the fetuses with normal outcome in the diabetic group. MPI has the potential to improve fetal surveillance in gestational diabetes.

Doppler ultrasonographic assessment of fetal middle cerebral artery peak systolic velocity in gestational diabetes mellitus

OBJECTIVE

To compare Doppler ultrasonographic measurements of the fetal middle cerebral artery peak systolic velocity (MCA PSV) among women with or without gestational diabetes mellitus (GDM).

METHODS

A cross-sectional study was conducted among pregnant women who presented for prenatal care at a single hospital in Brazil between September 11, 2015, and January 6, 2017. Patients were stratified into a group with GDM and a control group without GDM. One Doppler ultrasonographic assessment was performed per participant. This measurement was made after diagnosis but before the start of treatment among women in the GDM group. Fetal ultrasonographic and biometric variables assessed included MCA PSV, MCA pulsatility index, umbilical artery pulsatility index, the MCA-to-umbilical artery ratio, abdominal circumference, and weight.

RESULTS

The study included 238 women: 115 in the GDM group and 123 in the control group. The median MCA PSV was 1.02 in the GDM group and 1.08 in the control group (P=0.036). No statistically significant between-group differences were found for the other fetal ultrasonographic variables or for the fetal biometric variables assessed. None of the maternal or fetal parameters assessed displayed a linear correlation with MCA PSV.

CONCLUSION

Doppler ultrasonographic measurements of MCA PSV were lowered among the fetuses of women diagnosed with GDM.

Fetal thymus size in pregnant women with diabetic diseases

AIM

The aim of our study was to assess fetal thymus size in diabetic pregnancies compared with normal pregnancies.

METHODS

Sonographic fetal thymus size was retrospectively assessed in 161 pregnancies with maternal diabetes and in 161 uncomplicated pregnancies matched by gestational age. The anteroposterior thymic and the intrathoracic mediastinal diameter were measured and the quotient was calculated [thymic-thoracic ratio (TT-ratio)]. In addition, we defined the quotient of the anteroposterior thymic diameter and the head circumference as thymus-head ratio (TH-ratio). The maternal diabetes cases were subdivided into three groups: (1) diet-controlled gestational diabetes, (2) insulin-dependent gestational diabetes and (3) preexisting maternal diabetes.

RESULTS

TT-ratio and TH-ratio were smaller in pregnancies with maternal diabetes (P<0.001 and P<0.001, respectively). In all three maternal diabetes subgroups, the TT-ratio and the TH-ratio were lower compared with the control group (P<0.001 for each group).

CONCLUSIONS

Reduced fetal thymus size seems to be associated with diabetic pregnancy. We introduce fetal thymus size as a new potential prognostic parameter for maternal diabetes.

Determination of the fetal myocardial performance index in women with gestational impaired glucose tolerance and to assess whether this parameter is a possible prognostic indicator of adverse fetal outcome

AIM

The aim of this study was to investigate if the myocardial performance index (MPI) is altered in fetuses in women with gestational impaired glucose tolerance (GIGT), controlled on diet and whether this parameter is also predictive of adverse outcome in this group, as in poorly controlled gestational diabetes.

METHODS

In a prospective cross-sectional study, 32 women with GIGT on diet in the 3rd trimester were recruited and matched with 32 women with normal pregnancies (control group). Using Doppler echocardiography, the MPI was calculated. Placental resistance Doppler markers in both groups were also determined. An abnormal outcome was defined as any of the following: stillbirth, neonatal death, neonatal intensive care unit (NICU) admissions, tachypnea with pulmonary oedema, neonatal cord pH <7.15, five minute Apgar score <7, and cardiomyopathy.

RESULTS

The cases had a significantly higher median MPI compared to controls, p value <.0001. There were eight abnormal outcomes recorded in the 32 fetuses in the study group, corresponding to an adverse outcome rate of 25%. Fetuses with an adverse outcome had significantly higher MPI measurements compared to the GIGT fetuses with normal outcome. The MPI served as an excellent predictor of adverse outcome in the GIGT fetuses, with a total area under the ROC curve of 0.96. An MPI z-score greater than 4.0 conferred a sensitivity of 100% and specificity of 80%. No abnormal outcomes were noted in the control group.

CONCLUSIONS

The MPI is impaired in fetuses in GIGT women, with fetuses with an adverse outcome having significantly higher MPI measurements compared to the fetuses with normal outcome in the GIGT group. MPI has the potential to improve fetal surveillance in gestational diabetes.

Stillbirth in the pregnancy complicated by diabetes

Pregestational diabetes currently complicates 4% of pregnancies, while gestational diabetes complicates approximately 8% of pregnancies. Increased risk of stillbirth in diabetic pregnancies has been a well-known and recognized complication for decades. While stillbirth rates for diabetic pregnancies have decreased due to screening, treatment, and antenatal surveillance of these patients, about 4% of all stillbirths remain attributable to diabetes, and diabetic pregnancies continue to be at increased risk for perinatal mortality. The purpose of this article is to review the literature on the epidemiology, pathophysiology, and prevention, as well as future research, of diabetes-associated perinatal mortality.

Differences in post-mortem findings after stillbirth in women with and without diabetes

AIMS

The reason for the fivefold increased risk of stillbirth in women with diabetes is not known. Further understanding of the underlying mechanisms may facilitate identification of pregnancies at increased risk. We have compared post-mortem reports in matched pairs of stillbirths in women with and without diabetes.

METHODS

Post-mortem reports were provided by the Centre for Maternal and Child Enquiries. Stillbirths as a result of lethal congenital and genetic abnormalities were excluded. Whole body, placenta and organ weights and histo-pathological findings in cases and controls were compared and also related to published reference values.

RESULTS

We analysed post-mortem reports on 23 matched pairs of stillbirths from 2009 to 2010. Mean placental weight in women with diabetes was 75 g less than in control subjects (95% CI -143 to -7 g; P = 0.032). In maternal diabetes, the thymus was often small and showed a 'starry sky' pattern on histology in 11 of 20 cases compared with four of 22 controls (P = 0.03). This histological finding was associated with a particularly low mean placental weight z-score -2.1 (1.1) standard deviations below a reference population corrected for gestational age.

CONCLUSIONS

In over half of the stillbirths occurring in women with diabetes, there was a 'starry sky' appearance in the fetal thymus on histology, this being associated with a small placenta. These findings are consistent with a critical subacute metabolic disturbance being a prominent cause of the increased risk of stillbirth in pregnancies complicated by maternal diabetes.

Oxidant balance markers at birth in relation to glycemic and acid-base parameters

In diabetic pregnancies, suboptimal glycemic control is a risk factor for fetal acidemia and stillbirth. We hypothesized that the diabetic intrauterine milieu (hyperglycemia, hyperinsulinemia, changes in acid-base status) might predispose to oxidative stress. We studied 70 newborns whose mothers had pregestational diabetes (58 with type 1 diabetes mellitus) and 71 control newborns from nondiabetic mothers. Protein carbonyls (PCs), malondialdehyde, and 8-hydroxy-2'deoxyguanosine were measured in umbilical vein plasma as a reflection of protein, lipid, and DNA oxidative damage, respectively; glutathione peroxidase-3 (GPx3), an important circulating antioxidant enzyme, was also assayed. Despite satisfactory glycemic control in the majority of diabetic mothers, their newborns showed higher birth weight and relative hyperglycemia, hyperinsulinemia, and respiratory acidemia. The oxidant balance marker concentrations were not different at the P < .05 level between the 2 groups, and there was no relationship to maternal hemoglobin A(₁C) levels in the diabetic group. However, in the entire sample, increasing glucose levels at birth were related to lower GPx3 and higher PC concentrations; and GPx3 and PC concentrations were inversely correlated. In addition, a depressed pH or larger base-deficit at birth was related to higher PC and 8-hydroxy-2'deoxyguanosine concentrations. In conclusion, oxidant balance markers at birth are not affected by maternal diabetes per se and its long-term glycemic control, yet some markers are acutely tuned to metabolic cues including glucose and the acid-base environment.

Pregestational diabetes

The prevalence of preexisting diabetes in pregnancy is increasing largely because of an increase in type 2 diabetes. Outcomes of diabetic pregnancies for mother and newborn have improved greatly in recent decades from advances in understanding the disease process, improved education, and new treatment modalities delivered in a team approach. Nausea and vomiting from pregnancy and pregnancy-associated insulin resistance can make glycemic control a challenge. Care of women with preexisting diabetes demands careful monitoring in the preconception, prenatal, and peripartum periods.

Ductus venosus velocimetry in monitoring pregnancy in women with pregestational diabetes mellitus

OBJECTIVE

The purpose of this research was to assess the ability of ductus venosus (DV) Doppler velocimetry to predict adverse perinatal outcome in pregnancies complicated by pre-existing diabetes mellitus.

METHODS

This was a prospective study conducted at a tertiary referral obstetric facility in Brisbane, Australia. The study group included women with pregestational diabetes mellitus who delivered in the hospital between 1 January 1995 and 31 December 2006. The DV Doppler index was defined as abnormal if the DV peak velocity index for veins (PVIV) was equal to or greater than the 95(th) percentile for gestation. Adverse perinatal outcome included one or more of the following criteria: small-for-gestational-age infant; Cesarean section for non-reassuring fetal status; fetal acidemia at delivery; a 1-min Apgar score of <or= 3; a 5-min Apgar score of < 7; hypoxic ischemic encephalopathy; and stillbirth or neonatal death. The maternal characteristics and perinatal outcomes of pregnancies with normal or abnormal DV Doppler indices were compared.

RESULTS

Eighty-two pregestational diabetic pregnancies were studied and an abnormal DV-PVIV was identified in 25 (30.5%). Adverse perinatal outcome was identified in eight of 25 (32.0%) pregnancies with an abnormal DV-PVIV compared to seven of 57 (12.3%) pregnancies with a normal DV-PVIV (P < 0.05). The sensitivity of the DV-PVIV in predicting adverse perinatal outcomes in pregestational diabetic pregnancies was 53.3%, the specificity was 74.6%, the positive predictive value was 32.0% and the negative predictive value was 87.7%.

CONCLUSION

It may be useful to include DV-PVIV in the antenatal screening of pregnancies complicated by pregestational diabetes.

Erythrocytosis in offspring of mothers with Type 1 diabetes--are factors other than insulin critical determinants?

AIM

Maternal diabetes is associated with polycythaemia and thrombocytopaenia in the offspring; however, the relationship with fetal hormones is unknown. We assessed the association of maternal glycaemic control, birthweight and fetal hormones with haematological indices in pregnancies complicated by maternal diabetes.

METHODS

Prospective study using cord blood samples from 89 offspring of mothers with Type 1 diabetes (OT1DM) and 34 control offspring. Full blood count, insulin, leptin, adiponectin, cortisol, insulin-like growth factor 1 (IGF-1), insulin-like growth factor binding protein 3, intercellular adhesion molecule 1 and C-reactive protein were measured in the umbilical vein at birth.

RESULTS

Haematocrit was higher in OT1DM (OT1DM 0.55 +/- 0.17%, control offspring 0.51 +/- 0.06%; P = 0.02). The difference in platelets count was not statistically significant [OT1DM 214 x 10(9)/l (173-259); control offspring 253 x 10(9)/l (180-310), P = 0.06]. Maternal glycated haemoglobin (HbA(1c)) showed a moderate positive correlation with fetal haematocrit (r = 0.30, P = 0.02). Cord platelet counts were negatively associated with birthweight in OT1DM (r = -0.27, P = 0.01). In multivariate models, cord insulin was not associated with haematocrit, but cord leptin was negatively associated with platelets in control offspring (P < 0.001) and OT1DM (P = 0.046), with additional contributions from male sex (P = 0.08) in OT1DM, and IGF-1 (P = 0.04) and insulin (P = 0.04) in control offspring.

CONCLUSIONS

Fetal haematocrit is increased in response to diabetes in pregnancy and is related to maternal glycaemic control. Fetal hyperinsulinism, hyperleptinaemia or macrosomia, although readily demonstrable in this cohort, do not emerge as determinants of raised fetal haematocrit in OT1DM. Both increased birthweight and fetal leptin are negatively associated with platelet count.

TYPE 1 DIABETES IN PREGNANCY; INFLUENCES ON MOTHER AND FETUS

Type 1 diabetes complicates around 1 in 200 to 300 pregnancies in the United Kingdom. Historically maternal type 1 diabetes carried very high risks for mother and child. Introduction of insulin led to an immediate, marked decline in the previously very high rates of maternal mortality; in contrast an improvement in perinatal outcomes occurred more slowly but was nevertheless dramatic. This is strikingly demonstrated by the temporal decline in perinatal mortality in offspring of mothers with type 1 diabetes which was virtually universal before use of insulin in the 1920's, likely remained in excess of 20% even in the 1960's and fell to under 4% by the 1990's. The reasons for this more gradual improvement in perinatal outcomes cannot be defined with precision but will have been influenced by improved glycaemic management with use of intensive, multiple dose insulin treatment and home glucose monitoring; improvements in obstetric and neonatal management, and better management of complications of diabetes before and during pregnancy. In 1989 the St Vincent declaration proposed that pregnancy outcomes in women with type 1 diabetes should approximate those of the non-diabetic population. While the long term improvements in fetal outcomes have been dramatic, contemporary surveys confirm a persistent doubling or more of rates of congenital anomaly and a three to four fold increase in perinatal mortality in the UK and other European countries which will require further clinical innovation to overcome.

Diabetic-associated stillbirth: incidence, pathophysiology, and prevention

All forms of diabetes during pregnancy are associated with an increased risk for stillbirth, defined as fetal death at greater than 20 weeks. The incidence of stillbirth in women who have diabetes has decreased dramatically with improved diabetes care. Diabetic-associated stillbirth is associated with hyperglycemia, resulting in fetal anaerobic metabolism with hypoxia and acidosis. Prevention of stillbirth in women who have diabetes hinges on intensive multidisciplinary prenatal care with control of blood sugars and appropriate fetal surveillance.

Diabetic-associated stillbirth: incidence, pathophysiology, and prevention

All forms of diabetes during pregnancy are associated with an increased risk for stillbirth, defined as fetal death at greater than 20 weeks. The incidence of stillbirth in women who have diabetes has decreased dramatically with improved diabetes care. Diabetic-associated stillbirth is associated with hyperglycemia, resulting in fetal anaerobic metabolism with hypoxia and acidosis. Prevention of stillbirth in women who have diabetes hinges on intensive multidisciplinary prenatal care with control of blood sugars and appropriate fetal surveillance.

Abnormal Uterine Doppler Is Related to Vasculopathy in Pregestational Diabetes Mellitus

Background— The aim of the study was to evaluate the relation between maternal placental Doppler velocimetry, levels of the maternal glucose, and clinical signs of vasculopathy in pregnancy complicated by pregestational diabetes mellitus.

Methods and Results— A retrospective study of 155 pregestational diabetic women between the 22nd and 40th weeks of pregnancy, categorized in White classification as B, 49; C, 40; D, 22; R, 20; F, 5; and RIF, 19. Cases in classes R, F, and R/F were defined as having vasculopathy. Doppler velocimetry of umbilical and uterine arteries was evaluated for vascular impedance, both in terms of pulsatility index (PI) for both arteries and a notch in early diastole in the uterine arteries. The last examination before delivery was used for analysis. Increased umbilical artery PI was seen in 19 and a uterine artery abnormality in 45 cases. There was a correlation between levels of HbA lc and increased vascular impedance in the uterine and umbilical arteries. Signs of increased uterine artery vascular impedances were significantly related to pregestational vasculopathy. In cases of small-for-gestational-age newborn infants, PI was significantly increased in uterine and umbilical arteries. Furthermore, PI in macrosomic fetuses was significantly lower than in normal infants. Abnormal uterine artery Doppler was also strongly related to adverse outcome.

Conclusions— Abnormal uterine artery Doppler is related to pregestational vasculopathy and adverse outcome of pregnancy. The results suggest that the uterine arteries are affected in women with clinical signs of pregestational vasculopathy. This may influence placental perfusion and fetal well-being.

Computerized cardiotocography parameters in pregnant women affected by pregestational diabetes mellitus

AIM

To evaluate whether computerized CTG (cCTG) is a reliable method of predicting neonatal outcome in pregnancies complicated by pregestational diabetes at term.

PATIENTS AND METHODS

We considered 27 pregnant women affected by pregestational diabetes and 46 normal pregnancies as controls that fulfilled the following criteria: singleton, Caucasian, euglycemic pregnancies at term (>37 weeks gestational age). All women delivered by cesarean section (CS), with an antepartum cCTG performed within one hour before the CS and an UBGA available at birth. No patient was in labor during FHR monitoring.

RESULTS

Among cCTG parameters, accelerations 15 bpm, HV min, HV ms and STV were significantly lower in comparison to controls. We observed that in the diabetic pregnant women the parameter STV was not able to predict or to linearly regress with the most important UBGA parameters: pH and pCO2. Contrarily, in normal pregnancies, the STV linearly regressed with both the pH (p < 0.03) and pCO2 (p<0.04).

CONCLUSIONS

Computerized FHR criteria may not be applicable to fetuses in pregestational diabetic pregnancies at term. Therefore some criteria should perhaps be modified for a correct interpretation of cCTG in these pregnancies.

Exposure to maternal diabetes is associated with altered fetal growth patterns: A hypothesis regarding metabolic allocation to growth under hyperglycemic-hypoxemic conditions

The prevalence of diabetes is rising worldwide, including women who grew poorly in early life, presenting intergenerational health problems for their offspring. It is well documented that fetuses exposed to maternal diabetes during pregnancy experience both macrosomia and poor growth outcomes in birth size. Less is known about the in utero growth patterns that precede these risk factor expressions. Fetal growth patterns and the effects of clinical class and glycemic control were investigated in 37 diabetic pregnant women and their fetuses and compared to 29 nondiabetic, nonsmoking maternal/fetal pairs who were participants in a biweekly longitudinal ultrasound study with measurements of the head, limb, and trunk dimensions. White clinical class of the diabetic women was recorded (A2-FR) and glycosylated hemoglobin levels taken at the time of measurement assessed glycemic control (median 6.9%, interquartile range 5.6-9.2%). No significant difference in fetal weight was found by exposure. The exposed sample had greater abdominal circumferences from 21 weeks (P < or = 0.05) and shorter legs, but greater upper arm and thigh circumferences accompanied increasing glycemia in the second trimester. In the third trimester, exposed fetuses had a smaller slope for the occipital frontal diameter (P = 0.00) and were brachycephalic. They experienced a proximal/distal growth gradient in limb proportionality with higher humerus / femur ratios (P = 0.04) and arms relatively long by comparison with legs (P = 0.02). HbA1c levels above 7.5% accompanied shorter femur length for thigh circumference after 30 gestational weeks of age. Significant effects of diabetic clinical class and glycemic control were identified in growth rate timing. These growth patterns suggest that hypoxemic and hyperglycemic signals cross-talk with their target receptors in a developmentally regulated, hierarchical sequence. The increase in fetal fat often documented with diabetic pregnancy may reflect altered growth at the level of cell differentiation and proximate mechanisms controlling body composition. These data suggest that the maternal-fetal interchange circuit, designed to share and capture resources on the fetal side, may not have had a long evolutionary history of overabundance as a selective force, and modern health problems drive postnatal sequelae that become exacerbated by increasing longevity.

Neonatal hyperthyrotropinemia in gestational diabetes mellitus and perinatal complications

The aim of this study is to explore the relationship between high cord blood thyroid-stimulating hormone (TSH) level and in-utero stress to the fetus in gestational diabetes mellitus (GDM). Cord blood TSH results were analyzed in 1,578 euthyroid infants from singleton pregnancies with GDM: 103 with elevated TSH (>16 mIU/l) and 1,475 with normal TSH. Maternal characteristics, pregnancy outcome and perinatal complications were compared between the two groups. Multiple logistic regression was used to study the association between high cord blood TSH level and various perinatal complications which reflect in-utero stress in GDM after adjusting for the confounding effects of parity, instrumental delivery, cesarean section and baby gender. High cord blood TSH level was found to be associated with the 1-min Apgar score <7 (OR 3.31, 95% CI 1.78-6.16), birth trauma (OR 3.44, 95% CI 1.11-10.69), neonatal jaundice requiring treatment (OR 2.08, 95% CI 1.30-3.32), neonatal sepsis (OR 2.34, 95% CI 1.24-4.42), respiratory complications (OR 3.45, 95% CI 1.37-8.70), neurological complications (OR 8.01, 95% CI 1.91-33.60) and overall perinatal morbidity (OR 2.41, 95% CI 1.58-3.67). Cord blood TSH level seems to be a better and independent indicator of the in-utero stress to the fetus in GDM when compared to the commonly used sugar profile result and HbA1c level.

Fetal monitoring in type 1 diabetic pregnancies

Stillbirth and perinatal mortality rates are 5 times greater for an insulin-dependant diabetic mother than in the general population. Neonatal and infant mortality rates are 15 and 3 times greater, respectively. In addition, macrosomia is a major problem resulting in both fetal and maternal injury. Fetal monitoring is considered mandatory in such pregnancies. The rational approach would be to use surveillance strategies based on the underlying pathophysiology. However, in the diabetic pregnancy, the underlying pathophysiology is poorly understood and is likely to be multifactorial. Thus, in practice, a pragmatic approach is followed using methods that are applied in other high-risk pregnancies although the pathophysiology is different. Given the limitations in the predictive power of many fetal monitoring methods and the lack of randomised controlled trials, it is not surprising that there is no agreement over the best way to monitor fetal health in diabetic pregnancies. This article analyses the evidence regarding the value of these tests and proposed protocols for their use in the context of the diabetic pregnancy.

Audit on stillbirths in women with pregestational type 1 diabetes

OBJECTIVE

To audit stillbirth cases in women with type 1 diabetes to search for specific characteristics in order to improve antenatal care and treatment.

RESEARCH DESIGN AND METHODS

Retrospectively identified cases of stillbirths in women with type 1 diabetes during 1990-2000 were analyzed regarding characteristics of the mother, the pregnancy, glycemic control, and the stillborn. The cause of stillbirth was categorized as explainable, likely, or without obvious cause.

RESULTS

We found 22 women with 25 stillbirths among 1,361 singleton births by women with type 1 diabetes. In seven stillbirths the cause was categorized as explainable and in six as likely. In 12 cases no obvious cause was found; however, glycemic control was suboptimal in 9 of these cases. A total of 14 women reported daily smoking, and 10 of 19 with low education were unemployed.

CONCLUSIONS

Women experiencing stillbirth were characterized by a high incidence of suboptimal glycemic control, diabetic nephropathy, smoking, and low social status.

Reversal of foetal hydrops and foetal tachyarrhythmia associated with maternal diabetic coma

Foetal hydrops is always a challenge for the clinician. We report a case of tachycardia associated with hydrops and hydramnios in a pregnancy complicated with diabetic coma at 28 weeks gestation. Normal foetal heart rate was recorded immediately after correction of maternal acidotic status and hydrops eventually disappeared. The woman was delivered at 32 weeks and the baby had an uncomplicated postnatal course. We hypothesise that maternal ketoacidosis has been the precipitating factor of tachycardia and congestive heart failure and that this case is conceptually similar to the "late death" phenomenon, reported in cases of poorly controlled maternal diabetes.

Prediction of fetal acidaemia in pregnancies complicated by maternal diabetes mellitus by biophysical profile scoring and fetal heart rate monitoring

OBJECTIVE

To determine whether computer assisted fetal heart rate analysis or the biophysical profile score can provide noninvasive prediction of fetal acidaemia.

DESIGN

Cross sectional study.

SETTING

Harris Birthright Research Centre for Fetal Medicine, King's College Hospital School of Medicine, London.

SUBJECTS

Forty-one women with pregnancies complicated by diabetes mellitus.

INTERVENTIONS

Fetal heart rate (FHR) monitoring with computer assisted analysis, biophysical profile score (BPS) and cordocentesis for measurement of umbilical venous blood glucose concentration and blood gases, up to 24 h before delivery at 27 to 39 weeks gestation.

RESULTS

The mean umbilical venous blood pH was significantly lower than the normal mean for gestation, and was below the 5th centile in 18 pregnancies, including all six cases where the mother had nephropathy and hypertension. The mean pO2 was not significantly different from the normal mean for gestation. There were significant associations between fetal acidaemia and both the BPS (r = 0.46, P < 0.01) and FHR variation (r = 0.42, P < 0.01). However, of the 12 acidaemic fetuses of non-nephropathic mothers, nine had normal BPS and six had normal FHR variation.

CONCLUSIONS

In pregnancies complicated by maternal diabetes mellitus, BPS and FHR variation are of limited value in the prediction of fetal blood pH.

Placental and fetal Doppler velocimetry in pregnancies complicated by maternal diabetes mellitus

OBJECTIVE

Our purpose was to investigate placental and fetal circulation in pregnancies complicated by maternal diabetes mellitus and to relate any changes to fetal blood pH, Po2, and hematocrit.

STUDY DESIGN

Doppler measurements of both uterine arteries, one umbilical artery, the fetal descending thoracic aorta, and one fetal middle cerebral artery were performed in 65 well-controlled diabetic pregnancies in a cross-sectional study at the Harris Birthright Research Centre for Fetal Medicine, London. In 41 cases cordocentesis was also performed for the measurement of umbilical venous blood pH, Po2, and hematocrit.

RESULTS

The mean umbilical venous blood pH was significantly lower and the hematocrit significantly higher than the appropriate normal mean for gestation. However, the Doppler indices of the placental and fetal circulations were essentially normal, except in some of the cases complicated by preeclampsia or intrauterine growth retardation.

CONCLUSIONS

Maternal diabetes mellitus is not associated with abnormalities in Doppler indexes of the placental or fetal circulations.

Doppler velocimetry and fetal heart rate studies in nephropathic diabetics

OBJECTIVES

Our objectives were to determine in pregnancies complicated by diabetic nephropathy (1) if impedance to flow in the uterine and umbilical arteries is normal and (2) if these fetuses are hypoxemic and acidemic and if they have decreased fetal heart rate variation and Doppler blood flow redistribution.

STUDY DESIGN

In a cross-sectional study at the Harris Birthright Research Centre for Fetal Medicine, London, serial assessment of fetal heart rate variation and Doppler velocimetry of the placental and fetal circulations was undertaken in six pregnancies complicated by diabetic nephropathy. In all cases cordocentesis was performed within 24 hours before delivery for the measurement of umbilical venous blood gases.

RESULTS

Cordocentesis demonstrated these fetuses to be hypoxemic and acidemic. The fetal heart rate variation was decreased; however, impedance to flow in the uterine artery was normal, and increased impedance to flow in the umbilical artery with evidence of blood flow redistribution was observed in only one case.

CONCLUSIONS

Fetal hypoxemia and acidemia in pregnancies complicated by diabetic nephropathy is not a consequence of impaired placental perfusion, and the degree of metabolic derangement may be obscured by the apparent normal growth and failure of these fetuses to demonstrate blood flow redistribution.

Fetal polycythemia and thrombocytopenia in pregnancies complicated by maternal diabetes mellitus

In 40 pregnancies complicated by maternal diabetes mellitus umbilical venous blood was obtained by cordocentesis within 24 hours of elective delivery at 36 to 40 weeks' gestation. The mean fetal hematocrit was significantly higher and the mean platelet count significantly lower than the corresponding values of our reference ranges. Furthermore, blood gas analysis demonstrated these fetuses to be normoxemic but acidemic. The degree of fetal acidemia was significantly associated with both maternal and fetal blood glucose concentrations. The fetal hematologic indices were significantly related to the maternal glycosylated hemoglobin percentage but not to the degree of fetal acidemia or to the maternal or fetal blood glucose concentration at the time of cordocentesis. Fetal acidemia, polycythemia, and thrombocytopenia may contribute to the increased incidence of late unexplained intrauterine deaths in pregnancies complicated by maternal diabetes mellitus.