Changes in red blood cell oxygen transport in diabetic pregnancy

Association between neonatal hyperbilirubinemia and hypoglycemia in Chinese women with diabetes in pregnancy and influence factors

This retrospective study aimed to investigate the correlation between neonatal hyperbilirubinemia (NHB) and hypoglycemia (NH) in Chinese women with diabetes in pregnancy (DIP), and the influencing factors. All the data were collected July 1, 2017 and June 30, 2020, and 10,558 Chinese women with DIP and live births were included. Two separate multivariate binary stepwise forward logistic regression analysis calculated OR with 95% CI. The prevalence rates of NHB and NH was respectively 3.65% and 5.82% among women with DIP. The comorbidity of both diseases was 0.59%. NH were 1.81 times (OR 1.81, 1.19-2.76) more likely to have hyperbilirubinemia. NHB is positively correlated with NH (OR 1.93, 1.27-2.92). Increased gestational age has a protective effect on both NH (OR 0.76, 0.68-0.85) and NHB (OR 0.80, 0.69-0.92). Abnormal placental morphology is related to NH (OR 1.55, 1.16-2.08) and NHB (OR 1.64, 1.10-2.45). Regarding neonatal outcomes, congenital heart disease (CHD) (OR 2.16, 1.25-3.73; and OR 10.14, 6.47-15.90) was a risk factor for NH and NHB. NHB and NH were significantly correlated in women with DIP. The offspring of DIP with multiple risk factors have a significantly increased risk of neonatal hyperbilirubinemia.

Risk factors and outcomes for neonatal hypoglycaemia and neonatal hyperbilirubinaemia in pregnancies complicated by gestational diabetes mellitus: a single centre retrospective 3-year review

AIM

To determine risk factors associated with neonatal hypoglycaemia and hyperbilirubinaemia, and assess their impact on neonatal outcomes in pregnancies complicated by gestational diabetes mellitus (GDM).

METHODS

Retrospective review investigating all pregnancies complicated by GDM at Campbelltown Hospital (Sydney, Australia) between 1 January 2013 and 31 December 2015. Main outcomes measured were neonatal hypoglycaemia (capillary glucose levels < 1.8 mmol/l) and hyperbilirubinaemia (total serum bilirubin levels greater than age-appropriate thresholds for phototherapy). Adjusted odds ratios [95% confidence interval (CI)] are shown, calculated by multivariable logistic regression.

RESULTS

Some 60 (7.8%) infants developed hypoglycaemia, 58 (7.5%) developed hyperbilirubinaemia and 13 (1.7%) developed both. Risk of developing hypoglycaemia increased 1.8-fold (95% CI 1.3-2.6, P < 0.001) per gestational week at GDM diagnosis, 1.1-fold (95% CI 1.0-1.3, P = 0.04) per mmol/l maternal fasting glucose, 6.2-fold (95% CI 2.6-16.2, P < 0.001) with maternal history of macrosomia, 10.8-fold (95% CI 4.1-27.6, P < 0.001) with multiple pregnancy and 1.1-fold (95% CI 1.0-1.3, P = 0.04) per gestational week at birth. Risk of hyperbilirubinaemia increased with multiple pregnancy (26.4; 95% CI 11.7-59.7, P < 0.001), and 1.5-fold (95% CI 1.1-2.1, P = 0.01) per gestational week at GDM diagnosis. Hypoglycaemia was associated with a 2.8-fold (95% CI 1.1-7.1, P = 0.03) increased risk of macrosomia, a 5.4-fold (95% CI 1.1-27.3, P = 0.04) excess risk of shoulder dystocia and a 6.4-fold increased risk of 5-min APGAR ≤ 7 (95% CI 1.2-1.7, P < 0.001). Hyperbilirubinaemia was associated with an excess risk of polycythaemia (packed cell volume > 0.6; 97.1, 95% CI 38.9-241.5, P < 0.001).

CONCLUSIONS

Neonatal hypoglycaemia and hyperbilirubinaemia largely occur in different pregnancies. Both are associated with earlier GDM diagnosis; however, hypoglycaemia is more associated with maternal glycaemia and its sequelae, and hyperbilirubinaemia is associated with polycythaemia.

Women with pre-gestational diabetes have a higher risk of stillbirth at all gestations after 32 weeks

AIM

To explore the additional risk of stillbirths and to quantify that risk according to gestational age among women with diabetes.

METHODS

Data on pregnancies ending in 2007 and 2008 in women with pre-gestational diabetes in three English regional audits were identified. A prospective audit collected data on all pregnancies delivering between June 2010 and May 2011 in one region and in 13 other units across England. The data on all singleton pregnancies from these two cohorts were combined. Comparisons were made to all births in England and Wales for the same time period using data from the Office for National Statistics.

RESULTS

In the cohort of women with pre-gestational diabetes there were a total of 2085 singleton pregnancies, of which 29 resulted in a stillbirth (overall stillbirth rate 13.9 per 1000, 95% CI 9.7-19.9, relative risk compared with all pregnancies in England and Wales 2.73, 95% CI 2.61-2.84). The relative risk of stillbirth between 32 and 34 weeks' gestation was 4.95 (95% CI 4.24-5.78), 3.77 (95% CI 3.42-4.16) at 35 to 36 weeks, 5.75 (95% CI 5.43-6.09) for deliveries at 37 or 38 weeks and 7.34 (95% CI 6.52-8.25) for those born at 39 weeks or more.

CONCLUSION

Women with diabetes have a significantly higher risk of stillbirth at all gestations after 32 weeks and this additional risk is not just confined to pregnancies at 37 weeks or more.

Clinical and ultrasound features of placental maturation in pre-gestational diabetic pregnancy

BACKGROUND

Pre-gestational diabetes (PGDM) is a significant cause of neonatal morbidity and mortality. Delayed villous maturation (DVM) is a placental diagnosis with increased risk of perinatal mortality.

AIMS

This study aimed to prospectively look at the incidence of DVM in a PGDM population compared to non-diabetic controls. Additionally, we analysed antenatal ultrasound and clinical markers for DVM in the diabetic population.

STUDY DESIGN

This is a prospective study.

SUBJECTS

Placentae of women with non-diabetic and PGDM pregnancies underwent detailed blinded histo-pathological examination.

OUTCOME MEASURES

Clinical data, including birth weight, peri-natal outcome, and, in PGDM group, glycaemic control and ultrasound findings, were obtained.

RESULTS

77 non-diabetic women and 74 PGDM women consented to the study. The incidence of DVM in the PGDM group was higher than in the non-diabetic group (21/74 (28.4%) vs. 11/77 (14.3%) p=0.02; RR 1.98). In the PGDM group clinical and ultrasound markers were compared between the DVM group (n=21) and the non-DVM group (n=53). There was no difference in perinatal outcome nor glycaemic control between these two groups.

CONCLUSION

DVM, a placental finding with an increased risk of perinatal mortality, is increased in PGDM population compared to non-diabetic controls. No association was found with maternal glycaemic control. The presence of placental DVM was not associated with antenatal ultrasound parameters nor clinical perinatal outcome.

Diabetic parturient - Anaesthetic implications

Pregnancy induces progressive changes in maternal carbohydrate metabolism. As pregnancy advances insulin resistance and diabetogenic stress due to placental hormones necessitate compensatory increase in insulin secretion. When this compensation is inadequate gestational diabetes develops. 'Gestational diabetes mellitus' (GDM) is defined as carbohydrate intolerance with onset or recognition during pregnancy. Women diagnosed to have GDM are at increased risk of future diabetes predominantly type 2 DM as are their children. Thus GDM offers an important opportunity for the development, testing and implementation of clinical strategies for diabetes prevention. Timely action taken now in screening all pregnant women for glucose intolerance, achieving euglycaemia in them and ensuring adequate nutrition may prevent in all probability, the vicious cycle of transmitting glucose intolerance from one generation to another. Given that diabetic mothers have proportionately larger babies it is likely that vaginal delivery will be more difficult than in the normal population, with a higher rate of instrumentally assisted delivery, episiotomy and conversion to urgent caesarean section. So an indwelling epidural catheter is a better choice for labour analgesia as well to use, should a caesarean delivery become necessary. Diabetes in pregnancy has potential serious adverse effects for both the mother and the neonate. Standardized multidisciplinary care including anaesthetists should be carried out obsessively throughout pregnancy. Diabetes is the most common endocrine disorder of pregnancy. In pregnancy, it has considerable cost and care demands and is associated with increased risks to the health of the mother and the outcome of the pregnancy. However, with careful and appropriate screening, multidisciplinary management and a motivated patient these risks can be minimized.

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.

Quantitative studies on the villi, trophoblast and intervillous pores of placentae from women with well-controlled diabetes mellitus

Human placentae from well-controlled diabetic women were collected after 37 weeks of gestation and divided into three groups according to the duration and severity of diabetes mellitus established by White classification criteria. A fourth group of subjects served as matched controls. Various morphometric variables not estimated hitherto (including the star volumes of villous 'domains' and intervillous 'pores' and trophoblast surface denudation) were assessed stereologically. The aims were to test whether or not (1) control values of these structural quantities are preserved in well-controlled diabetes mellitus, and (2) differences occurred between alternative diabetic groups. Placental specimens were obtained by systematic random sampling procedures and paraffin sections were cut at random positions and orientations. Volume densities of peripheral (terminal+intermediate) villi and intervillous spaces were estimated by test point counting and multiplied by placental volumes in order to convert them into absolute volumes. Volume estimates were also obtained for trophoblast, syncytiotrophoblast nuclei and intervillous fibrin-type fibrinoid. Villous surface areas were estimated by intersection counting and the star volumes of villi and intervillous pores were obtained by measuring the lengths of point-sampled intercepts. Calculations were also made of the theoretical numbers of villous domains and intervillous pores and of the numbers of syncytiotrophoblast nuclei. No significant differences were detected between control and diabetic placentae, or between White classes, for any of the estimated quantities. It is concluded that normal values are preserved by good glycaemic control regardless of diabetic grouping.

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

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

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.

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.

Fetal distress during labour in diabetic pregnancy

The frequency of fetal distress in labour was studied in 46 diabetic women and in 46 non-diabetic matched controls. Fetal distress was assessed by electronic fetal heart rate (FHR) monitoring and fetal scalp blood pH determinations in late first stage of labour. Ominous FHR and/or low pH (less than 7.26) was more common in the diabetic group than in the control group (17.4% and 10.9%, respectively) but the difference was not statistically significant. The frequency of caesarean section and low Apgar score at 1 min was significantly higher in the diabetic group (P less than 0.05). There was no correlation between maternal blood glucose regulation and the occurrence of fetal distress in the diabetic group. The results suggest that fetal distress may be slightly more common in labour in diabetic women compared with controls managed in a similar way. Careful FHR monitoring and liberal use of fetal scalp blood pH determinations is recommended.

Delay in the fetal globin switch in infants of diabetic mothers

In the normal fetus, a switch from production of hemoglobin F (alpha 2 gamma 2) to hemoglobin A (alpha 2 beta 2) occurs at 28 to 34 weeks of gestation. In the fetus with beta-hemoglobinopathy or beta-thalassemia, this switch proceeds despite the morbidity that results when production of beta-globin is abnormal or reduced. Since insulin has recently been shown to induce renewed expression of some inactive genes, we studied globin biosynthesis during the natural evolution of the fetal globin switch under conditions of hyperinsulinemia, which occurs in infants of diabetic mothers. Such infants develop in a hyperglycemic environment, which produces reactive hyperinsulinemia. The normal increase in beta-globin production from pre-switch levels did not occur in 9 of 10 such infants at term, as compared with 11 normal infants, in whom the switch occurred by 36 to 39 weeks of gestation (P less than 0.0001). The delay in the switch from gamma-globin to beta-globin in this unique clinical setting may allow identification of physiologic factors that can modulate developmental gene suppression.