Observational Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. May 15, 2019; 10(5): 304-310
Published online May 15, 2019. doi: 10.4239/wjd.v10.i5.304
Association of hypoglycaemia in screening oral glucose tolerance test in pregnancy with low birth weight fetus
Ananth U Nayak, Arun M A Vijay, Radha Indusekhar, Sushuma Kalidindi, Venkata M Katreddy, Lakshminarayanan Varadhan
Ananth U Nayak, Arun M A Vijay, Radha Indusekhar, Sushuma Kalidindi, Venkata M Katreddy, Lakshminarayanan Varadhan, Combined Antenatal Diabetes Clinic, University Hospital of North Midlands NHS Trust, Stoke on Trent ST4 6QG, Staffordshire, United Kingdom
Author contributions: Nayak AU and Katreddy VM contributed to study conception and design and writing of article; Nayak AU contributed to data acquisition, data analysis and interpretation, and writing of article; all authors contributed to editing, reviewing and final approval of article.
Institutional review board statement: This study was an audit undertaken in the Joint Antenatal Diabetes clinic at University hospital of North Midlands NHS Trust (UHNM Trust) and was approved and presented at the departmental audit meeting in the UHNM Trust.
Informed consent statement: The use of relevant patient database was approved for undertaking this audit locally. There was no active patient intervention in this study and written patient consent was not needed as per the audit requirements.
Conflict-of-interest statement: There are no conflicts of interest to declare.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Ananth U Nayak, FRCP, MBBS, MRCP, Consultant Physician and RCP Tutor, Combined Antenatal Diabetes Clinic, University Hospital of North Midlands NHS Trust, Newcastle Road, Stoke on Trent ST4 6QG, Staffordshire, United Kingdom. ananth.nayak@nhs.net
Telephone: +44–1782–679997 Fax: +44–8436–365428
Received: March 18, 2019
Peer-review started: March 20, 2019
First decision: April 13, 2019
Revised: April 18, 2019
Accepted: May 1, 2019
Article in press: May 1, 2019
Published online: May 15, 2019
Processing time: 58 Days and 19.5 Hours
ARTICLE HIGHLIGHTS
Research background

Screening for gestational diabetes in high risk women during pregnancy is undertaken with oral glucose tolerance test (OGTT). This paper is an observational study auditing the prevalence of significant hypoglycaemia on the screening OGTT during pregnancy and exploring its impact on the birth weight, if any association with low birth weight (LBW). Currently those women identified as with hypoglycaemia on OGTT do not have any additional antenatal monitoring. Any association of such hypoglycaemia noted on the screening OGTT with LBW might help in targeting antenatal care in such women towards improving pregnancy outcomes.

Research motivation

The results of our study support allocation of resources for antenatal monitoring of women noted to have hypoglycaemia, especially the Asian ethnic cohort who appeared to be at higher risk of having babies with low birth-weight.

Research objectives

This study was undertaken to determine the prevalence of hypoglycaemia on the OGTT during screening for gestation diabetes in high risk women and explore any association with fetal birth weight.

Research methods

We audited data on all woman deemed high risk and had the screening OGTT during pregnancy identifying 3537 women who met the criteria and had the required complete data for analysis. Having defined hypoglycaemia (blood glucose ≤ 3.5 mmol/L) and categorizing birth weight as low (≤ 2500 g), normal (2500 to 4499 g) or Macrosomia (≥ 4500 g) we analysed the prevalence of hypoglycaemia on the OGTT screening and its association with birth weight using ANOVA to compare group means and logistic regression analysis to assess the factors independently predicting the low birth-weight.

Research results

In this audit on 3537 women deemed high risk as per NICE criteria and who had the OGTT screening, the proportion who has hypoglycaemia was 3.7%, majority of the hypoglycaemia being on the 2-h plasma glucose (2-h PG) value. 2.7% women had babies with LBW and this cohort had significantly lower fasting glucose (4.3 ± 0.6 mmol/L, P = 0.001) and a higher proportion of this cohort had 2-h PG ≤ 3.5 mmol/L compared to the cohorts with normal and macrosomic babies (8.3% vs 2.8% vs 4.2%; P = 0.007). The factors which predicted LBW were fasting plasma glucose, Asian ethnicity and 2-h PG ≤ 3.5 mmol/L. Maternal age, 2-h PG ≥ 7.8 mmol/L and HbA1c were not significant predictors of LBW.

Research conclusions

We observed the prevalence of hypoglycaemia in the screening OGTT during pregnancy to be about 3.7%. Such hypoglycaemia appears to be independently associated with risk of fetal LBW, and Asian ethnic origin being another risk factor for fetal low birth.

Research perspectives

This study on a large cohort of high risk women may improve awareness amongst clinicians about the potential impact of hypoglycaemia on birth weight and potentially help in considering assessment of fetal weight with serial growth scans as a part of antenatal care towards improving pregnancy outcomes. Future studies incorporating other risk factors associated with the fetal birth weight and studies looking at resource implications to implement the required fetal growth monitoring for such at-risk women with hypoglycaemia would be recommended.