Southend University Hospital NHS Foundation Trust Patient Information Service Women and children s business unit Gestational diabetes
What is gestational diabetes? Gestational diabetes mellitus (GDM) is a type of diabetes that occurs during pregnancy. It usually occurs during the second or third trimester of pregnancy, affecting between five to ten per cent of pregnant women. Blood sugars may rise during pregnancy because of hormonal changes which affect the action of insulin. Insulin is a hormone which helps to remove sugar from the blood and use it for energy in other parts of the body. The change in hormone levels causes insulin resistance, so during pregnancy, women increase the amount of insulin they produce by two to three times in order to keep blood sugar levels normal. Some women struggle to produce the amount of insulin required for pregnancy and so blood sugar levels rise, causing gestational diabetes. Diagnosis is usually confirmed by a glucose tolerance test (GTT). If your consultant, GP or midwife considers you are at risk of developing gestational diabetes they will refer you for the test between 26 and 28 weeks gestation. If you have had GDM in a previous pregnancy you will be offered a GTT or self monitoring of blood glucose as soon as possible after booking. If your body mass index (BMI) at the start of pregnancy is over 40 you will be referred for a GTT test between 16 to 18 weeks. A diagnosis of GDM will lead to increased monitoring, and may lead to more interventions, during both pregnancy and labour. However these interventions should improve the outcome of pregnancy for you and your baby. 1
How can gestational diabetes affect my pregnancy? The majority of women are unaware they have the condition until they have the blood test. However, it may cause you to feel tired, thirsty and pass larger than normal volumes of urine, but once blood sugars are at a normal level most of these symptoms disappear. You may be at risk of: Having a large baby Increased fluid around baby Induction of labour, instrumental delivery or caesarean section Birth complications such as shoulder dystocia (baby s shoulders getting stuck after delivery of the head). Your baby may be at risk of: Admission to neonatal unit Having low blood sugars following birth Breathing difficulties Obesity and/or diabetes developing later in the child s life A small risk of stillbirth. Managing your gestational diabetes with the support of your diabetes and pregnancy team will help to reduce these risks. 2
How is gestational diabetes monitored? Close monitoring and treatment reduces the risks for the babies and improves women s long term health. Following diagnosis of gestational diabetes you will be invited to attend the women s clinic for an appointment with a consultant obstetrician, diabetes specialist midwife, diabetes specialist nurse and dietician. You will be advised to test your own blood sugar levels every day for the remainder of your pregnancy. When you attend clinic the diabetes specialist midwife will give you instruction on how and when to test. Ideally blood sugar levels should be below 5.3mmols/L before meals and below 7.8mmols/L one hour after meals. If you have any concerns about your blood sugars then you should contact the diabetes specialist nurse/midwife for advice. A dietician will also see you to discuss your diet. Healthy eating is an important part of your treatment and will aid your ability to maintain normal blood sugar levels. Blood sugar control is improved by taking regular exercise such as walking or swimming. The baby s growth and fluid volume will be monitored regularly during your pregnancy by ultrasound scan. 3
What if my blood sugars remain high? Between ten per cent and twenty per cent of women with GDM require medication to control their blood sugars in pregnancy. If your blood sugars remain above 5.3mmols/L before meals and/ or above 7.8mmols/L after meals despite following advice about healthy eating and exercise, you may require Metformin tablets or insulin injections for the remainder of your pregnancy. You will be given full instruction on when to take the tablets or how to inject insulin using a pen device. In most cases of gestational diabetes the tablets or insulin will be stopped immediately following delivery of your baby. What happens after I have had my baby? Gestational diabetes usually disappears once the baby is born and you will be advised when you can stop monitoring your blood sugars. Breast feeding is recommended to assist baby s blood sugar control and you should aim to feed your baby as soon as possible after birth. Your baby will have his/her blood sugar levels monitored following delivery. You will be advised to stay in hospital for 24 hours and usually go home once baby s blood sugars are stable. It is recommended you have a blood test 6 to 12 weeks after the baby has been born to make sure the diabetes has gone. 4
Ideally you should have a blood test every year to exclude diabetes as there is a 50 per cent risk of developing Type 2 diabetes in later life. Approximately five to ten per cent of women will go on to develop Type 1 diabetes at some time during their life. Maintaining physical activity and avoiding obesity can help to prevent the development of diabetes. Will I get gestational diabetes in future pregnancies? You are more likely to develop gestational diabetes again if you have had it in previous pregnancies. However, if you are overweight and lose weight between pregnancies you may reduce your risk. It is advisable to continue the lifestyle advice about weight control, diet and exercise after the baby has been born. When planning for future pregnancies you should have a blood test to make sure you have not developed diabetes. Contact the DSM as soon as you have booked for your next pregnancy for support and advice. 5
Contact numbers Diabetes specialist midwife: Telephone 01702 385512 or 01702 435555 ext 8337 or email: diabetesmidwives@southend.nhs.uk Diabetes specialist nurses: Telephone 01702 385072 Diabetes specialist dietitian: Telephone 01702 385331 Antenatal triage unit 7.15am to 8.30pm: Telephone 01702 385301 Diabetes UK careline: Telephone 0345 123 2399 Or go on line Diabetes UK: www.diabetes.org.uk 6
Southend University Hospital NHS Foundation Trust Patient Information Service If this leaflet does not answer all of your questions, or if you have any other concerns please contact the diabetes specialist midwife on: 01702 385512. www.southend.nhs.uk For a translated, large print or audio tape version of this document please contact: Patient Advice & Liaison Service (PALS) Southend University Hospital NHS Foundation Trust Prittlewell Chase Westcliff-on-Sea Essex, SS0 0RY Telephone: 01702 385333 Fax: 01702 508530 Email: pals@southend.nhs.uk Written by S. Miall and PIPMS Reviewed and revised by Sara Miall Reviewed and revised June 2017 Leaflet due for revision June 2019 Form No. SOU1463 Version 7