Gestational Diabetes Mellitus (GDM)

Introduction

This reflective account assesses gestational diabetes mellitus (GDM). This reflection is written in accordance with Driscoll’s (2000) reflective cycle. For the purpose of this reflection pseudonyms have been used in accordance with The Code, written by Nursing and Midwifery Council (NMC, 2015), respecting individuals rights to privacy and confidentiality.

My current placement is on the antenatal day unit (ANDU), where pregnant women attend appointments for various reasons such as cardiotocography trace (CTG) for reduced fetal movements (RFM), 28 week bloods or any routine bloods required, booking appointments, full antenatal check, abdomen pain, suspected spontaneous rupture of membranes (SROM), vaginal bleeding, raised blood pressure (BP) and we conduct daily appointments for oral glucose tolerance testing (OGTT). On Tuesday mornings the day unit runs a GDM clinic, where women have an antenatal check (urinalysis and BP) and report their blood glucose results to the specialist diabetes midwife. Following this, women attend a routine growth scan to check the rate in which the fetus is growing and amniotic fluid volume check, followed by an appointment with a Consultant Obstetrician. After the Consultant appointment there is a dietitian available to discuss diet controlled GDM. This reflection assesses GDM and therefore follows this path of appointments for one woman named Isabel, who was diagnosed with GDM four weeks previous.

Isabel

Isabel is a gravida one, parity zero, gestation 32 weeks, who attended the ANDU four weeks ago for an OGTT due to her raised body mass index (BMI) of 31 kg/m2 (NICE, 2015). Before Isabel attended her appointment she was advised to not eat after 10pm the night before and to only drink water, this is to obtain an accurate fasting plasma glucose level (NICE, 2015). When Isabel arrived onto the ANDU we then asked ‘have you eaten or drunk anything other than water since 10pm last night?’, Isabel stated she had only drank water. If Isabel had eaten or drunk anything other than water the test could not be conducted, due to not being able to obtain an accurate fasting plasma glucose reading (Local trust guidelines, 2016). OGTT consists of a fasting blood test (basal), followed by drinking a 75g glucose drink (Marshall and Raynor, 2014, p. 257). In line with Trust Guidelines (2016) the woman must remain seated in the waiting area and not drink anything other than water. Two hours after drinking the 75g glucose drink, a second blood test is taken with consent to determine the two hour plasma glucose level (NICE, 2015). Both blood tests are then sent off for analysis and 48 hours later ANDU are sent the blood results. Diagnosis for GDM occurs if the woman has either:

• A fasting plasma glucose level of 5.6 mmol/litre or above or

• A two hour plasma glucose level of 7.8 mmol/litre or above (NICE 2015).

Isabel had a fasting plasma glucose level of 5.4 mmol/litre and a two hour plasma glucose level of 7.9 mmol/litre, which confirmed she had GDM. GDM is a form of diabetes that can emerge in the second or third trimester of pregnancy. After 20 weeks gestation the body has an increasing maternal insulin resistance (Marshall and Raynor, 2014, p. 259). GDM is formally non-insulin dependant, therefore initial treatment is diet controlled to regulate glucose levels and reduce weight. Increased physical activity can improve glucose tolerance and control GDM (Marshall and Raynor, 2014, p. 259). GDM is an intolerance to glucose which is accredited to increasing levels of placental hormones, specifically human placental lactogen (hPL). It is not possible in pregnancy to differentiate between Type 1, Type 2 diabetes (which do not resolve following birth of the fetus) and GDM, which is why women are made aware of a follow up appointment postnatally to check diabetes is not still present (Marshall and Raynor, 2014, p. 261).

Approximately 700,000 women give birth each year, out of this figure up to 5% of women have pre-existing diabetes or GDM (NICE, 2015). Locally this year to date there have been over 350 cases of women testing positive for GDM in pregnancy (Local trust guidelines, 2018). GDM usually resolves itself after the birth of the baby (Marshall and Raynor, 2014, p. 259). Women with a previous history of GDM in pregnancy are routinely tested after the booking appointment (NICE, 2015). GDM is usually asymptomatic but is associated with the following:

• Family history of type 2 diabetes or GDM

• Increasing maternal age

• Certain ethnic groups (Asian, African-Caribbean, Latin American, Middle Eastern)

• Previous unexplained stillbirth

• BMI at booking greater than 30 kg/m2

• Previous fetal macrosomia

• Smoking

• An inter pregnancy weight gain of more than three BMI points doubles the risk of GDM (Marshall and Raynor, 2014, p. 259).

• Polycystic ovarian syndrome (PCOS)

However, Local trust guidelines (2016) state some symptoms of GDM may include going to the toilet more often, feeling really tired and excessive thirst. These are symptoms which can be present in normal pregnancy but the midwife can test for GDM if a woman has any of these symptoms (Local trust guidelines, 2016). The midwife would also recommend OGTT if glycosuria of 2+ or above is detected on one occasion or if 1+ or above is detected on two or more occasions by urine reagent strip testing, during routine antenatal appointment as this may indicate undiagnosed GDM (NICE, 2015).

When Isabel was diagnosed with GDM she was invited to attend an appointment at the antenatal clinic (ANC) with the diabetes specialist midwife to discuss the diagnosis. It was explained to Isabel that changing her diet and doing light exercise (30 minutes each day), meant she would hopefully manage to diet control her GDM diagnosis (Marshall and Raynor, 2014, p. 261). Isabel understood this meant self monitoring her blood glucose levels at home (her best friend had previously had GDM in her last pregnancy, which meant Isabel had an awareness of the process) and once a week emailing all the results to the diabetes specialist midwife. Isabel self monitored her blood glucose levels daily by testing her fasting and one hour post meal blood glucose level in line with NICE (2015). With diet controlled GDM the aim is to maintain the blood glucose levels below the following figures:

• Fasting: 5.3 mmol/litre

• One hour after meals: 7.8 mmol/litre

• If testing two hours after meals: 6.4 mmol/litre (NICE, 2015).

As I first met Isabel at 32 weeks gestation she already had a good understanding of her GDM diagnosis and was attending the ANC for a routine follow up appointment to discuss her readings for the previous week, followed by a fetal growth scan, amniotic fluid volume check, Consultant appointment and a meeting with the dietitian if required. I introduced myself to Isabel and gained consent to be present during her various appointments (NMC, 2015). Isabel had a routine antenatal check first (BP and urinalysis, both within normal parameters). Isabel went through her blood glucose levels from the previous week which were as follows:

My mentor discussed these results with Isabel and reassured her that mostly she was managing to diet control her GDM. However, the readings in red suggested that on these days something she was eating was presenting high glucose readings. Isabel disclosed that on Thursday and Saturday she had brown bread toast with butter for breakfast, two slices and did not have this on the other days, opting for porridge instead. We advised Isabel that perhaps two slices of brown bread toast and butter was presenting a higher reading and perhaps try having one slice or just have porridge as that seemed to keep the readings within normal parameters. Isabel agreed with my mentors advice and decided to try this over the next week to see if the readings remained under 7.8 mmol/litre. Isabel disclosed she was having an egg salad for lunch most days and this was working well for her, as her readings always remained under 7.8 mmol/litre one hour after lunch. The post one hour dinner readings proved to be high on three occasions over the last week, Isabel stated on Monday night she had pasta, Friday night a jacket potato with salad and Sunday a roast dinner including roast potatoes. My mentor discussed portion sizes with Isabel as two of the meals contained potato and the other pasta, which are carbohydrates. A small amount of carbohydrates are ok as they provide energy but if portion sizes are excessive this can give a high blood glucose reading, this is because carbohydrates turn into sugar (Gestational Diabetes UK, 2018). We then provided Isabel with a diabetes UK magazine, which contained further information on GDM and had an extensive range of meal ideas. We also advised Isabel to have a chat with the dietitian after her consultant appointment. My mentor also advised Isabel that the Consultant may suggest taking metformin as blood glucose targets had not fully been met. NICE (2015) guideline state, if targets are not met within one-two weeks after diagnosis then commencement of metformin is recommended. Metformin is effective for GDM when diet can not control the blood glucose levels, as it decreases the amount of glucose produced by the liver, and assists in making your body’s own natural insulin work properly (NICE, 2018).

Isabel was now due to have an ultrasound scan (USS) to check fetal growth and amniotic fluid volume. NICE (2015) guideline recommends women with GDM to have four weekly growth scans and amniotic fluid volume check from 28 weeks to 36 weeks gestation. Fetal growth is routinely checked with women with GDM as they are at increased risk of fetal macrosomia (weighing more than 4.5 kg) and intrauterine growth restriction (IUGR) and small for gestational age (SGA). Isabell’s USS’s to date had all been normal, with growth following the 50th centile. Amniotic fluid volume had also been normal, this was the same at today’s 32 week scan. Amniotic fluid volume is checked due to increased risk of polyhydramnios (Gestational Diabetes UK, 2018). Other complications that can arise in pregnancy due to GDM are:

• Premature birth < 37 weeks

• Stillbirth

• Miscarriage

• Placenta insufficiency

• Pre-eclampsia

• Neonatal problems such as: Hypoglycemia and jaundice (Gestational Diabetes UK, 2018).

After Isabell’s USS she attended a meeting with her Consultant Obstetrician who checked over the details from the USS and was happy with the growth of the fetus and amniotic fluid volume. The Consultant asked Isabel how she was coping with controlling the GDM diagnosis with diet and exercise alone? Isabel presented the Consultant with her recent blood glucose readings (see above). The Consultant agreed that mostly Isabel was recognising what foods kept her blood glucose levels within normal parameters, but some days the levels are still in line with/above the recommendation of 7.8 mmol/litre. The specialist midwives suggestion of commencing metformin was an accurate statement, as inline with NICE (2015) metformin is to be offered if blood glucose levels are still high for one-two consecutive weeks, as this means targets are not being met with exercise and diet alone. The side effects were explained to Isabel, which commonly are abdominal pain, diarrhoea, nausea, taste disturbances and vomiting and in rare cases decreased B-12 absorption (NICE, 2018). Isabel consented to being prescribed metformin, she was to start initially on 500mg once daily with breakfast (NICE, 2018). Isabel was invited back in one weeks time for review, to see if the dose was high enough to reduce blood glucose levels. At this point Isabel did not want to wait to see the dietician as the current waiting time to see her was one hour, instead stating she would try some of the meal plans provided in the magazine the specialist diabetes midwife gave her. With this Isabel went to pick up her prescription and I thanked her for letting me observe the care she received throughout the morning, and we said our goodbyes.

I initially felt quite shocked at the amount of women who are diagnosed with GDM each year, especially locally with a total of 350+ women diagnosed so far to date. This made me think; Are we talking enough about diet and exercise at the booking appointment? Personally I think from what I have observed so far in my training I would say diet is not discussed enough. I think the rates of GDM could be decreased if women had a better understanding of the implications of poor diet. I think this is part of a bigger conversation though, mainly focusing on pre-conceptual care. If women and their partners who are trying for a baby, had an appointment to discuss their health before becoming pregnant, then perhaps GDM could be avoided for some women. However, this mostly focuses on women diagnosed with GDM due to raised raised BMI or poor diet, and does not take into account women with GDM due to family history, PCOS and does not focus on certain ethnic groups (Asian, African-Caribbean, Latin American, Middle Eastern).

Women with PCOS are at increased chance of developing GDM due to being insulin resistant and being pregnant increases glucose intolerance in the body. A common symptom of PCOS is obesity which is also a risk factor for GDM. Women who have PCOS are recommended metformin for treatment as it reduces insulin resistance and insulin secretion, which also helps with treatment for GDM (PCOS, 2018). Women with PCOS are recommended to have an OGTT by 28 weeks gestation (Local trust guidelines, 2016)

Research suggests that women from certain ethnic groups (Asian, African-Caribbean, Latin American, Middle Eastern) are two-four times more likely to develop GDM than those from Caucasian backgrounds (Diabetes UK, 2018). Hedderson, Darbinian and Ferrara (2014) conducted a multi ethnic cohort study examining the prevalence of GDM and found a significant variation in the risk of GDM occurring in different ethnic groups. Asian Indian women had the highest prevalence of GDM, Asian sub-groups such as; Chinese, Southeast Asian and Filipina also had a high prevalence of GDM. In contrast non-Hispanic white and black women had the lowest prevalence. The study linked individuals with GDM to known risk factors such as raised BMI, age, parity and lack of education on diet and exercise (Hedderson, Darbinian and Ferrara, 2014). When investigating ethnic groups and why they seem to have a higher prevalence of developing GDM, I noticed a real lack of information explaining why. As a student midwife I feel it is important to know why GDM occurs more frequently in certain ethnic groups and would like to feel confident in explaining this to women in the future, I have not seen this being explained in placement so far.

I found observing the care Isabel received really interesting as I had so far in my training not had much exposure to GDM. I felt she was really well supported by the specialist diabetes midwife, by her consultant and due to her diagnosis had received excellent continuity of carer. Everything was explained fully, including the risks and benefits of being prescribed metformin due to raised blood glucose levels. I did wonder at the time when the Consultant would be discussing a care plan for labour with Isabel. Once Isabel had left, I spoke to the Consultant who stated that this was discussed with Isabel at her first initial appointment, when she received her GDM diagnosis. The Consultant stated; Induction of labour is recommended from 37 weeks gestation with Isabel’s consent, otherwise CTG monitoring is advised from 38 weeks and await spontaneous birth. However, it is advised for Isabel as her GDM has been uncomplicated to date, to not give birth any later than 40+6 weeks gestation. This advice is in accordance with NICE (2015) diabetes in pregnancy guideline. At any point if Isabel’s GDM worsened or if any complications arose with the fetus regarding grow or amniotic fluid volume then the care plan may change.

Reference list

Diabetes UK (2018) Facts And Stats. Available at: https://diabetes-resources-production.s3-eu-west-1.amazonaws.com/diabetes-storage/migration/pdf/DiabetesUK_Facts_Stats_Oct16.pdf (Accessed: 13 May 2018).

Driscoll, J. (2000) Practising clinical supervision: A reflective approach for healthcare professionals. Kent: Bailliere Tindall

Gestational Diabetes UK (2018) Complications of gestational diabetes. Available at: https://www.gestationaldiabetes.co.uk/complications/ (Accessed: 11 May 2018).

Hedderson, M., Darbinian, J. and Ferrara, A. (2014) Disparities in the risk of gestational diabetes by race-ethnicity and country of birth. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4180530/ (Accessed: 13 May 2018).

Marshall, J. and Raynor, M. (2014) Myles textbook for Midwives. 6th edn. London: Elsevier.

NICE (2015) Diabetes in pregnancy: management from preconception to the postnatal period. Available at: https://www.nice.org.uk/guidance/ng3 (Accessed: 11 May 2018).

NICE (2018) Metformin Hydrochloride. Available at: https://bnf.nice.org.uk/drug/metformin-hydrochloride.html#interactions (Accessed: 11 May 2018).

NMC (2015) The Code: Professional standards of practice and behaviour for nurses and midwives. Available at: https://www.nmc.org.uk/globalassets/sitedocuments/nmc-publications/nmc-code.pdf (Accessed: 1 March 2018).

PCOS (2018) Gestational Diabetes and PCOS. Available at: https://pcos.com/gestational-diabetes-and-pcos/ (Accessed: 13 May 2018).