What does Gestational Diabetes mean?

According to the World Health Organization (WHO), gestational diabetes is a pregnancy medical complication, defined as a glucose tolerance disorder causing a hyperglycemia of variable severity, starting or first diagnosed during pregnancy, regardless of the necessary treatment and its postpartum evolution.

The GD related risks are linked to the severity of the hyperglycemia and an appropriate management helps reduce maternal-fetal complications.

Frequency of Gestational Diabetes/ How common is GD?

  • GD is the most common complication in pregnancy,
  • with a variable global prevalence of 06 % to 17%,
  • and 19% in case of multiparity.

In Algeria, 02 epidemiologic surveys have been conducted as per WHO methodology and criteria (see table).

When using the new IADPSG criteria, the frequency of DG changes from single (simple) to double. Considering that GD is a risk factor for type 2 diabetes, we value the importance of its screening, management and post follow-up in the immediate and future postpartum..

What are GD risk factors?[1]

  • Family history
  • 1st degree relatives of type 2 diabetes
  • Macrosomic siblings
  • Family obesity
  • Early vascular (hypertension, coronary artery disease, stroke),
  • Non-obstetrical personal history
  • Macrosomia history (birth weight≥ 4000 g),
  • Obésité constitutionnelle de la patiente [L’obésité ou la surcharge pondérale avant la grossesse sont identifiés comme facteurs de risque de diabète gestationnel, la valeur seuil d’indice de masse corporelle (IMC) est ≥ 25 kg/m²]
  • Age ≥ 35 years old,
  • HTA
  • Gestational Diabetes
  • Obstetric history
  • Spontaneous abortion
  • Unexplained in utero death
  • Macrosomia or intrauterine growth delay
  • Congenital malformations
  • Previous gestational obesity (> 15Kg)
  • Hydramnios -HTA
  • Pregnancy Polycystic ovarian syndrome
  • On the current pregnancy
  • Macrosomia
  • Repeated urinary infections
  • Hydramnios
  • Excessive weight gain
  • Glycosuria
  • High blood pressure or toxemia of pregnancy

What are the short term maternal consequences of GD?

  • Urinary infections (12.4%)
  • Hypertension artérielle gravidique (21,2 % vs 7,1 %) p<0,002)[2]
  • Increase in cesarean section rate (30.3% vs 10.3% p < 0.003)

What are the short termfœtal and neonatal consequences of GD?

  • Perinatal mortality: No significant difference, in case of good glycemic control.
  • Fetal macrosomia: can be defined by a greater weight than a threshold value of 4000 g
  • Metabolic complications [3]
    • Hypoglycémie : glycémie < 0,30 g/l à terme et < 0,20 g/l chez le prématuré ((66,7 % vs 1 ; 6 %) p<0.001)
    • Hypocalcémie : calcémie < à 80 mg/l à terme
  • Other complications
    • Shoulder dystocia
    • Respiratory and cardiac complications
  • Transfer to intensive care unit

Screening for Gestational Diabetes

  • An international consensus has been poposed in 2010 by the IADPSG [1](International Association of diabetes and Pregnancy Study Group) screening and diagnosis methods of GD
  • In the first trimester: Experts recommend performing a fasting blood sugar(on empty stomach) or glycated hemoglobin (HbA1c at 6.5% threshold) in early pregnancy in order to screen patients with previous type 2 diabetes or unknown.
  • In the 24th and 28th week of amenorrhea: For all pregnant women whose GAJ was < 0.92 g / l, or not screened in the 1st trimester, it is recommended to perform a glucose OGTT of 75 g (Test of WHO).

What are the diagnostic criteria for GD?

One pathological value allows the diagnosis of gestational diabetes to be measured. (See table)

Which pregnant women should be screened?

The CNGOF and the SFD (2010) [1] provide targeted screening: In the presence of one or more of the following risk factors (see table)

What are the glycemic objectives?

In the current state of knowledge, the currently validated objective is to obtain a blood sugar level on empty stomach below 0.95 g / L (grade A). To date, there is no intervention study validating the threshold of 0.92 g / L as a therapeutic objective. There are no data suggesting to favoring the postprandial measurement at one hour or two hours, nor the thresholds to be retained: 1.30 g / L or 1.40 g / L at one hour or 1.20 g / L at 2 hours. The latter is currently advisable (grade A).

What are the therapeutic measures?

  • Dietary measures [1]:
  • 1st treatment of the GD
  • Alowing to achieve blood sugar targets in 20 to 70% of cases.
  • Must be individualized: 1800 to 2000 kcal / d (50% carbohydrate)
  • Physical activity[2]:
  • Walking, swimming

What are the requirements for an optimal diabetes self-monitoring?

  • It will be based according to the same therapeutic principles, from the pregnancy planning to delivery. An optimized insulin therapy and intensified blood sugar self-monitoring, combined with an appropriate diet.
  • Blood glucose Self-monitoring allows to monitor patients and indicate insulin therapy (grade C). . When women are being treated with insulin, ASG is needed to adjust insulin dosage.ASG is recommended between 4 and 6 times a day [3] (at least once on an empty stomach and two hours after meals depending on the treatment – diet or insulin – and the obtained balance (professional agreement). ASG must be followed until the immediate postpartum period. The devices must be calibrated according to the procedures in place.
  • Insulin therapy is indicated when diet is insufficient to achieve (or maintain) blood sugar goals.
  • Immediate postpartum
  • Blood glucose monitoring for a few days to ensure return to normal.
  • Adjusted contraception.
  • Reclassification of diabetes 6 to 12 weeks after childbirth
  • Long-term monitoring: OGTT every 12 to 24 months.

What will happen in the medium term for mothers who have experienced a GD?

  • Recurrence of diabetes in subsequent pregnancies : 25 to 36% / OMS criteria (29.7% series of the thesis of Pr M. BACHAOUI EHU Oran)
  • 15 to 60% become diabetic within 20 years (26.8% within 12 years series of the thesis of Pr M. BACHAOUI EHU Oran)

What is the long-term future of children?

  • Obesity (after the first years of life)

Diabetes (earlier and more common)

[2] Tobias & al, Physical activity before and during pregnancy and risk of gestational diabetes mellitus a meta-analysis. Diabetes care 2011; 34:223-9.

[3] Guidelines developed by the French National College of Gynecologists and Obstetricians (CNGOF) and by the French Speaking Society of Diabetes (SFD), Extract from Métabolic Diseases Medicine – December 2010 – Vol. 4 – N ° 6

[1] Mimouni-Zerguini S. Gestational Diabetes: risk factors, evolution and perinatal consequences. Medicine of Metabolic Diseases – December 2009 – Vol. 3

[2] P48 – S. Bensalem & al Fetal-maternal morbidity in women with gestational diabetes in the Wilaya of Constantine

[3] P48 – S. Bensalem & al Fetal-maternal morbidity in women with gestational diabetes in the Wilaya of Constantine

[4] International Association of Diabetes and Pregnancy Study Groups Consensus Panel, International Association of Diabetes and Pregnancy Study Groups Recommendations on the Diagnosis and Classification of Hyperglycemia in Pregnancy , Diabetes Care 33, no. 3 (mars 1, 2010) : 676 -682.

[5] Guidelines developed by the French National College of Gynecologists and Obstetricians (CNGOF) and by the French Speaking Society of Diabetes (SFD), Extract from Métabolic Diseases Medicine – December 2010 – Vol. 4 – N ° 6

[6] Zhang & al, Dietary fiber in intake, Dietary glycemic load and risk for gestational diabetes mellitus. Diabetes care; 29:2223-30.

[7] Tobias & al, Physical activity before and during pregnancy and risk of gestational diabetes mellitus a meta-analysis. Diabetes care 2011; 34:223-9.

[8] Guidelines developed by the French National College of Gynecologists and Obstetricians (CNGOF) and by the French Speaking Society of Diabetes (SFD), Extract from Métabolic Diseases Medicine – December 2010 – Vol. 4 – N ° 6