This is a guide about diabetes mellitus during pregnancy, signs and symptoms, risk factors, effects, both to the pregnancy and child and nursing management
2. INTRODUCTION
• Diabetes mellitus is a chronic metabolic disorder due to either insulin
deficiency or due to peripheral tissue resistance (decreased sensitivity
to the action of insulin)
• The pathophysiology involved are:
Decreased sensitivity of skeletal muscles and liver to insulin (insulin
resistance) and
Inadequate secretion of insulin
3. Definitions
• Insulinopenia- resulting to a form of diabetes mellitus that results
from an inadequate secretion of insulin
• Hyperinsulinemia- the amount of insulin in your body is higher than
what is considered normal
• MODY- maturity onset diabetes of the young- a rare form of diabetes
which is caused by mutation
• Renal threshold- the lowest blood glucose level that correlated with
the first detectable appearance of urine glucose which is 180 mg/dl
(10.0 mmol/L)
4. TYPES OF DM
• Type–1 (IDDM) is characterized by young age onset (Juvenile) and
absolute insulinopenia. They have genetic predisposition with
presence of autoantibodies.
• Type–2 (NIDDM) is characterized by late age onset, overweight
woman and peripheral tissue (skeletal muscle, liver)insulin resistance
(hyperinsulinemia). Genetic predisposition is also observed.
• Gestational Diabetes Mellitus (GDM)
• Others: Genetic, Drugs, MODY
5. INCIDENCE OF DIABETES MELLITUS DURING
PREGNANCY
• About 1–14% of all pregnancies are complicated by diabetes mellitus
and 90% of them are gestational diabetes mellitus (GDM).
• Nearly 50% of women with GDM will become overt diabetes (type-2)
over a period of 5 to 20 years.
6. GESTATIONAL DIABETES MELLITUS (GDM)
NOMENCLATURE
• GDM is defined as carbohydrate intolerance of variable severity with onset
or first recognition during the present pregnancy.
• The entity usually presents late in the second or during the third trimester.
• The definition is used irrespective of the fact that the condition persists
after pregnancy or not.
• Majority of these women (>50%) with GDM ultimately develop overt
diabetes by next 15 to 20 years.
• It appears that many of these women diagnosed as GDM, are already
suffering from impaired b-cell function but remained undetected. These
cases are basically pre-existing type 2 diabetes.
8. RISK FACTORS
• The potential candidates for GDM are:
• (a) Positive family history of diabetes (parents or sibling). Family history should
include uncles, aunts and grandparents.
• (b) Having a previous birth of an overweight baby of 4 kg or more
• (c) Previous stillbirth with pancreatic islet hyperplasia revealed on autopsy
• (d) Unexplained perinatal loss
• (e) Presence of polyhydramnios or recurrent vaginal candidiasis in present
pregnancy
• (f) Persistent glycosuria
• (g) Age over 30 years
• (h) Obesity
• (i) Ethnic group (East Asian, Pacific island ancestry).
10. SCREENING:
• While some advocate screening routinely to all pregnant mothers, others reserve
it only for the potential candidates.
• Screening strategy for detection of GDM are:
• (a) Low risk—Absence of any risk factors as mentioned above → blood glucose
testing is not routinely required
• (b) Average risk—Some risk factors → perform screening test
• (c) High risk—Blood glucose test as soon as feasible.
• The method employed is by using 50 gm oral glucose challenge test without
regard to time of day or last meal, between 24 weeks and 28 weeks of pregnancy.
• A plasma glucose value of 327 mg% or that of whole blood of 130 mg% at 1 hour
is considered as cut off point for consideration of a 100 gm (WHO– 75 gm)
glucose tolerance test
11. HAZARDS
• (1) Increased perinatal loss is associated with fasting hyperglycemia.
Fetal anomalies are however not increased. This is due to the absence
of metabolic disturbance during organogenesis
• (2) Increased incidence of macrosomia
• (3) Polyhydramnios
• (4) Birth trauma
• (5) Recurrence of GDM in subsequent pregnancies is about 50%.
12. MANAGEMENT
• Diet with 2,000–2,500 Kcal/day for normal weight woman and restriction
to 1,200–1,800 Kcal/day for over weight woman is recommended.
Carbohydrate should be 40–50% of total calories.
• The patient needs more frequent antenatal supervision with periodic
checkup of fasting plasma glucose level which should be less than 90 mg%.
• The control of high blood glucose is done by restriction of diet, exercise
with or without insulin.
• Human insulin (NovoRapid®) should be started if fasting plasma glucose
level exceeds 5.0mmol/L and 2 hours postprandial value is greater than
6.7mmol/L(repetitive) even on diet control.
• Nearly 25% women with GDM need insulin therapy.
• Exercise (aerobic, brisk walking) programs are safe in pregnancy and may
obviate the need of insulin therapy.
13. Obstetric management:
• Women with good glycemic control and who do not require insulin
may wait for spontaneous onset of labor. However, elective delivery
(induction or cesarean section) is considered in patients requiring
insulin or with complications (macrosomia) at around 38 weeks.
14. • Follow-up: Nearly 50% of women with GDM would develop overt
diabetes over a follow-up period of 5–20 years. Women with fasting
hyperglycemia have got worse prognosis to develop type-2 diabetes
and cardiovascular complications.
• Recurrence risk in subsequent pregnancy is more than 50%.
15. EFFECTS OF DIABETES ON PREGNANCY
• Abortion: Recurrent spontaneous abortion may be associated with
uncontrolled diabetes.
• Preterm labor (26%) may be due to infection or polyhydramnios.
• Infection: Urinary tract infection.
• Increased incidence of preeclampsia (25%).
• Polyhydramnios (25–50%) is a common association.
16. References
• Hiralal konar, DC Dutta’s textbook of obstetrics, 8th edition pg 325-334
• Marshal J, Raynor M, Myles textbook for midwives, 16th edition, pg
257-262