Niamh Daly

The relationship between gestational weight gain and fetal growth: time to take stock?

Abstract The aim of this article is to review the current evidence on gestational weight gain (GWG). Maternal obesity has emerged as one of the great challenges in modern obstetrics as it is becoming increasingly common and is associated with increased maternal and fetal complications. There has been an upsurge of interest in GWG with an emphasis on the relationship between excessive GWG and increased fetal growth. Recent recommendations from the Institute of Medicine in the USA have revised downwards the weight gain recommendations in pregnancy for obese mothers. We believe that it is time to take stock again about the advice that pregnant women are given about GWG and their lifestyle before, during, and after pregnancy. The epidemiological links between excessive GWG and aberrant fetal growth are weak, particularly in obese women. There is little evidence that intervention studies decrease excessive GWG or improve intrauterine fetal growth. Indeed, there is a potential risk that inappropriate interventions during the course of pregnancy may lead to fetal malnutrition that may have adverse clinical consequences, both in the short- and long-term. It may be more appropriate to shift the focus of attention from monitoring maternal weight to increasing physical activity levels and improving nutritional intakes.

The interplay between maternal obesity and gestational diabetes mellitus

Abstract There is a strong epidemiological association between maternal obesity and gestational diabetes mellitus (GDM). Since the publication of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study on women with mild hyperglycemia in 2008, new criteria have been introduced in maternity services internationally for the diagnosis of GDM. As a result, the diagnosis of GDM may be made in one-third of obese women (n=68). The aim of this review was to examine the interplay between maternal obesity and GDM in light of the HAPO study and the subsequent revised diagnostic criteria. Obesity and GDM are important obstetric risk factors because they both are potentially modifiable. However, the new international criteria for the diagnosis of GDM have serious resource implications for maternity services provided to the large number of women attending for care in developed countries. Further consideration needs to be given as to whether obese women with mild hyperglycemia need to be referred to a multidisciplinary team antenatally if they do not require insulin treatment.

Maternal folic acid supplementation trends 2009–2013

We analyzed trends in folic acid supplementation among women booking for antenatal care between 2009 and 2013.

Maternal bacteremia and the Irish maternity early warning system

To assess whether introduction of the Irish maternity early warning system (IMEWS) in 2013 has improved the recording of vital signs among women with proven maternal bacteremia.

Trends in maternal obesity in a large university hospital 2009–2013

Maternal obesity has been identified as an important clinical priority in contemporary obstetrics. This study aimed to determine the incidence of maternal obesity in early pregnancy and track recent trends in body mass index (BMI) categories over 5 years 2009–2013.

Comparison of Citrate-Fluoride-EDTA with Fluoride-EDTA Additives to Stabilize Plasma Glucose Measurements in Women Being Screened during Pregnancy with an Oral Glucose Tolerance Test: A Prospective Observational Study

To the Editor: We recently highlighted the importance of implementing recommended preanalytical standards to avoid missing the diagnosis of gestational diabetes mellitus (GDM)1(1). The placement of samples on an ice slurry with separation within 30 min, however, is not always practical. We therefore carried out a prospective observational study to compare the incidence of GDM and mean glucose concentrations after stabilizing maternal glucose samples with a citrate-fluoride-EDTA (CFE) tube with the incidence after stabilization with fluoride-EDTA (FE) tubes. Both index tests were benchmarked against the ideal reference (2). Selectively screened women were recruited with consent when they presented for a routine 24–32 weeks oral glucose tolerance test (OGTT). Exclusion criteria were multiple pregnancy, age <18 years, and inability to understand English. The primary outcome was any increased glucose concentration diagnostic for GDM at the time of a 75-g OGTT using the International Association of Diabetes and Pregnancy Study Groups (IADPG) criteria (3). We included 121 women with tripled samples to determine the effect of sample handling on the incidence of GDM. ANOVA and McNemars test were used to determine statistical significance. We obtained 3 venous samples at …

National variations in operative vaginal deliveries in Ireland.

To compare the percentage of operative vaginal delivery (OVD) among all publicly funded maternity hospitals in Ireland and to develop quality control performance tables to facilitate national benchmarking.

How safe is preterm operative vaginal delivery and which is the instrument of choice

Abstract Objective: The objective of this study was to determine neonatal outcomes in preterm operative vaginal delivery given the current paucity of data available to guide clinicians. Study design: A retrospective review of 64 cases was conducted, and neonatal outcomes were compared to spontaneous vaginal deliveries in similar gestations. The primary outcomes studied were death and occurrence of intraventricular haemorrhage. Secondary outcomes included admission to NICU, Apgar <3 at 5 min, ventilation requirement, jaundice requiring treatment, culture-proven sepsis and necrotising enterocolitis. The study was conducted in a stand-alone maternity unit of approximately 9000 deliveries per year. Results and conclusions: We concluded that although vacuum delivery is avoided in preterm infants, outcomes were similar to forceps deliveries of similar gestations.

Laboratory diagnosis of gestational diabetes mellitus

Worldwide, gestational diabetes mellitus (GDM) is a common and serious pregnancy complication with potentially lifelong consequences for the woman and her offspring. There is remarkably little consensus, however, about the diagnosis of GDM despite the publication of the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study. The HAPO study aimed to clarify the risk of adverse outcomes associated with maternal glucose intolerance less severe than thresholds for GDM, in the absence of treatment. After excluding 1.8% with overt DM at the time of a 75-g oral glucose tolerance test (OGTT) in 15 centres, the odds ratios were calculated for adverse pregnancy outcomes. There was a continuous association between maternal glucose levels and increased birthweight and cord blood serum C-peptide levels. Maternal glycaemia was more weakly associated with primary caesarean section and clinical neonatal hypoglycaemia. One feature of the HAPO study was the rigorous standardisation of glucose measurements and the integration of local and central laboratory functions. This was a challenge for such a large study because of the wide geographical dispersion of the centres. After publication, the International Association of Diabetes and Pregnancy Study Groups (IADPSG) convened a meeting of over 220 delegates, including authors of the HAPO study. Based on thresholds from the HAPO study that identified pregnancies in which the risks of various adverse outcomes were increased with an odds ratio of 1.75 compared with mean glucose concentrations, a sub-group recommended new criteria for the diagnosis of GDM. They recommended a one-step 2-hour 75-g OGTT, which is accepted for screening outside pregnancy, lower thresholds for abnormal plasma glucose measurements and that the diagnosis could be made on the basis of one abnormal result, and not two as previously. Applying the new criteria post hoc to the women who participated in the HAPO study meant that 17.1% would have been diagnosed with GDM, in addition to the 1.8% excluded. These criteria were adopted subsequently by the World Health Organization. However, agreement among international healthcare organisations has not been universal. The American Congress of Obstetricians and Gynecologists recommends the two-step approach and the 100-g OGTT with higher thresholds for abnormality. In 2015, the National Institute for Health and Care Excellence (NICE) published guidelines for the diagnosis of GDM based on the 2-hour 75-g OGTT. After reviewing data from the four UK HAPO centres and data from a Norwich study, however, NICE recommended a higher fasting threshold for abnormality based on cost-effectiveness. Despite reviewing the same scientific evidence, consensus among experts about the diagnosis of GDM remains elusive. However, the debate has focused on the clinical diagnosis and effective management of GDM, and the associated economic costs. To date, scant attention has been given to the important laboratory components of the diagnosis of GDM. Laboratory glucose measurements are well-established and are based on enzymatic reactions involving one of four enzymes: glucose 1-dehydrogenase, glucose oxidase, glucokinase, or hexokinase. The most common methods of glucose analysis use one of the latter three enzymes. Glucose oxidase is the most specific enzyme and reacts only with D-glucose. The glucokinase or hexokinase methods are considered more accurate than the glucose oxidase method. Glucose oxidase or glucose 1-dehydrogenase are usually used for point-of-care tests. In recent years, however, the influences of preanalytical effects on laboratory results have received considerable attention. The effects can be categorised broadly into physiological, sample collection and other influences. These effects are particularly important in the measurement of

Time And temperature affect glycolysis in blood samples regardless of fluoride-based preservatives: a potential underestimation of diabetes

Background The inhibition of glycolysis prior to glucose measurement is an important consideration when interpreting glucose tolerance tests. This is particularly important in gestational diabetes mellitus where prompt diagnosis and treatment is essential. A study was planned to investigate the effect of preservatives and temperature on glycolysis. Methods Blood samples for glucose were obtained from consented females. Lithium heparin and fluoride-EDTA samples transported rapidly in ice slurry to the laboratory were analysed for glucose concentration and then held either in ice slurry or at room temperature for varying time intervals. Paired fluoride-citrate samples were received at room temperature and held at room temperature, with analysis at similar time intervals. Results No significant difference was noted between mean glucose concentrations when comparing different sample types received in ice slurry. The mean glucose concentrations decreased significantly for both sets of samples when held at room temperature (0.4 mmol/L) and in ice slurry (0.2 mmol/L). A review of patient glucose tolerance tests reported in our hospital indicated that 17.8% exceeded the recommended diagnostic criteria for gestational diabetes mellitus. It was predicted that if the results of fasting samples were revised to reflect the effect of glycolysis at room temperature, the adjusted diagnostic rate could increase to 35.3%. Conclusion Preanalytical handling of blood samples for glucose analysis is vital. Fluoride-EDTA is an imperfect antiglycolytic, even when the samples are transported and analysed rapidly provides such optimal conditions. The use of fluoride-citrate tubes may offer a viable alternative in the diagnosis of diabetes mellitus.