Preconception Counseling and Management of Diabetic Patients During Pregnancy

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Preconception Counseling and Management of
Diabetic Patients During Pregnancy

• Ghorbani H.MD

Fellow of Endocrinology Research Institute for
Endocrine Sciences 2007 Oct-18
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Preconception Counseling

• Prepregnancy evaluation and counseling of women
  DM ? minimize the risk to the FM
• Poor glycemic control during organogenesis?
  spontaneous abortion congenital anomalies
• Thus, the importance of evaluating glycemic
  control before conception cannot be overstated.

Uptodate 2007
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Preconception Care of Women With Diabetes

• Congenital malformations 6-9 vs. general
  population risk of 2- 3.
• Congenital defects account for 50 of perinatal
  mortality
• Diabetes associated malformations are more often
  lethal or significantly disabling and generally
  involve 1 or more organ systems.
• Spontaneous abortion in poorly controoled
  diabetes twice the rate in women without
  diabetes.

J Perinat Neonat Nurs Vol. 18, No. 1, pp. 1425 c
2004
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CONGENITAL MALFORMATIONS AND SPONTANEOUS
ABORTIONS

• The malformations most commonly associated with
  diabetes occur before the 7th week after
  conception
• The finding of multiple associated anomalies
  suggests a"hit"during blastogenesis that occurs
  during the first 4 weeks of fetal
  development
• Anomalies during blastogenesis tend to be more
  severe than those that occur during
  organogenesis (weeks 4 to 5 after conception)
• And may increase the risk of spontaneous abortions

joslins textbook 2005
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• Thus, interventions to control glycemia and
  reduce the risk of malformations must begin
  before conception and continue through
  the first 7 weeks after conception.

joslins textbook 2005
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Preconception Care of Women With Diabetes

• The institution of strict glycemic control, as
• soon as the woman with diabetes determines
• that she is pregnant, very often is too late
• to prevent structural damage to fetal organs
• which have already formed.

J Perinat Neonat Nurs Vol. 18, No. 1, pp. 1425 c
2004
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Management of women with diabetes before
conception

• Information and counselling should be provided to
  all women of reproductive age with diabetes
• A meta-analysis has demonstrated a significantly
  lower prevalence of major congenital anomalies in
  offspring of women who attended for prepregnancy
  counselling (relative risk, 0.36 95 CI,
  0.220.59 absolute risk, 2.1 v 6.5).

MJA Volume 183 Number 7 3 October 2005
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PERICONCEPTIONAL CARE OF WOMEN WITH DIABETES

• Because most pregnancies of diabetic women are
  either unplanned
• or
• without prenatal care until organogenesis has
  occurred, the efficacy of the intervention has
  been limited.
• Education combined with accessibility to
  preconception care is the cornerstone of care

Obstet Gynecol Clin N Am 34 (2007) 225239
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A complete history and physical examination
should be performed at the preconception visit.
This evaluation should include
Information on the duration and type of diabetes
History of acute and
chronic complications
Current and past glucose management
Physical activity, comorbid medical
conditions Gynecologic and
obstetric history Family
issues.
Uptodate 2007
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Diabetes complications review

• Retinopathy
• The eye examination should be conducted
  through dilated pupils by a person
  experienced in retinal examination.
• Preexisting retinopathy may progress more
  rapidly in pregnancy.
• Retinopathy that requires laser therapy
  should be treated before pregnancy.

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Nephropathy

• Overnight or 24 hour urine sample to quantify the
  albumin excretion rate.
• Patients with pre-existing microalbuminuria are
  more likely to develop preeclampsia
• If renal function is significantly impaired
  (crgt 0.2mmol/L), there is an increased risk of
  progression to dialysis during pregnancy

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Nephropathy

• In patients with diabetic nephropathy and mild
  to moderate renal dysfunction ( cr 1.4 mg/dL
  and GFR over 90 mL/min), pregnancy per se
  does not worsen long-term outcom
• Pregnancy seems to accelerate renal function
  
• deterioration in women with moderate to severe
  renal dysfunction at the beginning of
  pregnancy.

Obstet Gynecol Clin N Am 34 (2007) 225239
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Macrovascular disease

• Pre-existing heart disease, requires
  cardiological review before conception
• Significant CHD should be treated before
  pregnancy.

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 Ideally, all antihypertensive drugs should be
stopped before conception if the BP remains below
130/80 mmHg with dietary salt restriction.
Management of hypertension

• Methyl dopa
• Hydralazine
• B-blocker
• Ca canal blocker
• ACEI and ARBs are contraindicated
• Thiazid is relatively contraindicated
• BP should be managed aggressively

Uptodate 2007
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Autonomic neuropathy

• The presence of autonomic neuropathy resulting in
  gastroparesis, orthostatic hypotension or
  hypoglycaemic
• unawareness may severely complicate the
  management of
• diabetes in pregnancy.
• Other related issues
• Thyroid function should be measured for women
  with T1D

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Management of hyperlipidemia

• Statins are contraindicated should be
  discontinued before conception
• Hypertriglyceridemia treat with diet ,
  supplementation with medium chain TG and
• use of intravenous heparin

Joslin text book 2005
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Bacteriuria

•  Women should be screened for asymptomatic
  bacteriuria and those with positive test results
  should be treated to prevent development of
  pyelonephritis

Uptodate 2007
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Preconception Counseling

• Clinically proven ischemic CAD ?pregnancy is
  contraindicated.
• women with diabetic Autonomic neuropathy
  involving the
• CV system ? fixed heart rate ? pregnancy should
  be avoided.
• Gastroenteropathy is a relative contraindication
  to pregnancy.
• Women with active untreated PR should be
  counseled to delay pregnancy until after laser
  photocoagulation

J Perinat Neonat Nurs Vol. 18, No. 1, pp. 1425 c
2004
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Preconception Treatment Goals

• Goal Plasma(mg/dl)
  Wholeblood(mg/dl)
• Fasting and Premeal 80-110
  70-100
• glucose
• 2-hpp 100-155
  90-140
• HbA1c lt7normal if
  possible
• Avoid hypoglycemia

Joslin text book 2005
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WHITE CLASSIFICATION OF DM DURING PREGNANCY

• Gestational DM
• Class A diet alone ,any duration or age
• Class B age at onset gt 20 y duration lt 10y
• Class C age at onset 10- 19 or duration 10
  19 y
• Class D age lt 10 y or duration gt 20 y or
  background retinopathy or HTN ( not preeclampsia)
• Class R proliferative retinopathy or vitreous
  HE
• Class F nephropathy with p. uria gt 500 mg
• Class RF R F
• Class H heart dx
• Class T prior renal transplantation

Joslin textbook 2005
joslins textbook 2005
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Postconception Ttreatment Goals

• Goal
  Plasma whole blood
• Fasting and premeal glocose 70 -106 60
  -95
• BS -1hpp 100
  -155 90 -140
• BS -2hpp 90
  -130 80 -120
• Urinary ketones
  Negative
• Normalization of HbA1c
• Avoidance of severe hypoglycemia

Joslin textbook 2005
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Management during pregnancy

• Routinely review women every 14 weeks during the
  first 30 weeks and then every 12 weeks until
  delivery, depending on diabetes control and the
  presence of diabetic and obstetric complications.
• It is recommended that tests be performed fasting
  and 12 hours after meals.
• The HbAlc level should be monitored every 48
• weeks and kept within the normal range.

MJA Volume 183 Number 7 3 October 2005
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Management during pregnancy

• Women should be monitored for signs or
  progression of diabetic complications,
  particularly
• 
  Retinopathy
• 
  Proteinuria
• Proteinuria should be assessed by dipstick at
  regular intervals, and quantitated where
  appropriate.

MJA Volume 183 Number 7 3 October 2005
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• Complications of Diabetes during Pregnancy

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NEPHROPATHY

• pregnancy per se does not appear to hasten the
  natural progression to ESRD for most women
• This depends upon the initial degree of renal
  impairment.
• The risk is substantially increased in women with
  a cr above 2.0 mg/dL , many of whom have more
  than 2 g of proteinuria per day.

Uptodate 2007
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NEPHROPATHY

• These findings can be considered relative
  contraindications to pregnancy.
• A GFR below 50 mL/min before pregnancy is
  associated with a high prevalence of HTN and
  fetal wastage

Uptodate 2007
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The four major factors that have been associated
with the development and progression of DN

• Microalbuminuria
• Degree of glycemic control
• Blood pressure
• Pregnancy

Uptodate 2007
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Lowering BP, reducing microalbuminuria, and
improving glycemic control have a protective
effect on the glomeruli and decrease the GFR
CCBs may have similar renal protective effects as
ACEI

• These agents are a reasonable option for the
  treatment
• of HTN in pregnant women with DN,microalbuminuria,
  
• or microvascular disease.

Uptodate 2007
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EFFECT OF NEPHROPATHY ON PREGNANCY

• Overt nephropathy is associated with a variety of
  pregnancy
• complications
• Fetal growth restriction
• Nonreassuring fetal status
• Preeclampsia
• As a consequence, preterm delivery and cesarean
  birth are often required for maternal
  or fetal indications.

Uptodate 2007
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Hypertensive disorder

• Patients with preexisting diabetes are at
  increased risk of hypertensive complications
  during pregnancy
• Chronic HTN
• Preeclampsiaeclampsia
• Preeclampsia--eclampsia superimposed
  on chronic HTN
• Gestational HTN

joslins textbook 2005
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Hypertensive disorder

• Chronic HTN before or up to 20th weeks of
  gestation if HTN continue after 12 week after
  pregnancy
• Preeclampsia-eclampsia 140/90 mmhg ,usually
  after 20th weeks of gestation with proteinuria
  more than 300mg/24 hrs
• Preeclampsia-eclampsia superimposed on chronic
  HTN
• Gestational HTN

joslins textbook 2005
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Hypertensive disorder

• Start treatment from BP 130/ 80 mmHg
  especially if microalbuminuria or proteinuria is
  present

joslins textbook 2005
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Ophthalmic assessmen

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• Comprehensive eye examinatin in pt with
  planing for pregnancy
• who become pregnant should have a
  comprehensive eye examination in the first
  trimester and close f/u throughout pregnancy and
  for one year postpartum.
• Frequent monitoring is helpful to look for
  early worsening of retinopathy as
  glycemic control improves
• Laser photocoagulation should be considered
  for women with severe preproliferative
  diabetic retinopathy.

Uptodate 2007
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Retinopathy

• Risk of progression of retinopathy increase in
  pregnancy
• Risk is influenced with
• severity of baseline retinopathy
• HbAlc more than 6 SD above normal
• intensively treated pt has 1.6 fold increase
  risk of retinopathy
• Conventionally treated pt has 2.4 fold increase
  in retinopathy
• In DCCT study ,no difference in level of
  retinopathy in pt who became pregnant as
  compared with pt who never p.

joslins textbook 2005
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Management during pregnancy

• Formal eye review should be at least 3-monthly
  if
• baseline retinopathy is present
• If there is a rapid improvement in glycaemic
  control
• There has been a long duration of pre-existing
  diabetes.

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Frequency of testing during pregnancy in women
with pregestatonal diabetes

• Test
  Frequency
• Hemoglobin A1c Every 4-6
  weeks
• Blood glucose Home
  measurements 4-8 times daily
• Urine ketones During
  period of illness when any blood
  
  glucose value is gt 200 mg/dl
• Urine protein
  Diptstick , quantitate 24 hour
  
  excretion each trimester in women
  with
  nephropathy
• Serum creatinine Each
  trimester in women with nephropathy
• Thyroid function tests Baseline
  measurements of serum free T4 and TSH
• Eye examination Baseline and then
  as necessary per retinal specialist

Uptodate 2007
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Fetal Surveillance

• The priciple is to verify fetal viability in the
  first trimester
• Validate fetal structural integrity in the second
  trimester
• Monitor fetal growth during most of the third
  trimester
• And ensure fetal well-being in late third
  trimester

Maternal- Fetal Medicine Textbook 2004
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Fetal surveillance

• In the past, unexplained fetal death occurred in
  10-30 of type 1 diabetic pregnancies associated
  with macrosomia, hydramnios, preeclampsia,and
  vascular disease.
• Fetal surveillance is of utmost importance in
  optimizing a good outcome for both mother and
  fetus

Endocrinol Metab Clin N Am 35 (2006) 7997
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US is the most useful tool for the assessment of
the fetus.
Fetal surveillance

• It can be used to
• Estimate gestational age
• Screen for structural anomalies
• Evaluate growth
• Assess amniotic fluid volume
• Determine fetal status dynamically
  through Doppler
• and biophysical studies

Endocrinol Metab Clin N Am 35 (2006) 7997
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Fetal surveillance

• Macrosomia is usually defined as fetal weight
  greater than 4.0 kg to 4.5 kg or birth weight
  above the 90th percentile for gestational age
• Macrosomia occurs in approximately 88 of
  fetuses in whom the abdominal circumference and
  estimated fetal weight both exceed the 90th
  percentile

Endocrinol Metab Clin N Am 35 (2006) 7997
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Fetal surveillance

• US is essential for the evaluation of congenital
  anomalies.
• A structural ultrasonogram can detect both neural
  tube defects and major cardiac defects
• US is performed in the third trimester for the
  assessment of
• growth and development and the presence of
  macrosomia.

Endocrinol Metab Clin N Am 35 (2006) 7997
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Antepartum surveillance

• In women who have diet-controlled gestational
  diabetes, fetal surveillance is not initiated
  usually until 40 weeks
• Most centers defer testing until the 35th week
  if there is excellent glycemic control, but
  testing is started much earlier in women who have
  poor control, nephropathy,or hypertension

Endocrinol Metab Clin N Am 35 (2006) 7997
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Fetal surveillance in type I and type II
diabetic pregnancies

• Time
  Test
• Preconception Maternal glycemic control
• 8-10 w sonographic crown rump
  measurement
• 16 w Maternal serum alpha-
  fetoprotein level
• 20-22 w highresolution
  sonography, fetal cardiac
  
  
  
  echography in
  women in suboptimal diabetic control
  at first
  prenatal visit
• 24w Baseline sonographic
  growth assessment of the fetus
• 28 w Daily fetal movement
  counting by the mother
• 32 w Repeat sonography for
  fetal growth
• 34 w Biophysical testing
  
• 2X weekly NST or
  
• weekly CST
  or
• weekly
  biophysical profile
• 36w Estimation of fetal
  weight by sonography
• 37-38.5 w Amniocentesis and delivery
  for patients in poor control
• 38.5 40 w Delivery without
  amniocentesis for patients in good control who
  have
  excellent dating criteria
  
  

Maternal- Fetal Medicine Textbook 2004
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TESTS OF FETAL WELL - BEING
comment Reassuring result frequency test
Performed in all patients Ten movement in lt60 min Every night from 28 w Fetal movement counting
Being at 28-34 w with insulin dependent diabetes Two heart rate acceleration in 20 minutes Twice weekly Non- stress test
Same as for non stress test No heart rate decelerations in response to 3 contrations in 10 minutes weekly Contraction stress test
3 movement 2 1 flexion 2 30 sec breathing 2 2 cm amniotic fluid 2 Score of 8 in 30 minutes weekly Ultrasound biophysical profile
Maternal- Fetal Medicine Textbook 2004
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CONFIRMATION OF FETAL MATURITY BEFORE
INDUCTION OR PLANNING CESAREAN

• Phosphatidyl glycerol gt 3 in amniotic fluid
  collected from vaginal pool or by amniocentesis
• Completion of 38.5 weeks gestation
• Normal LMP
• First pelvic examination before 12 weeks confirm
  dates.
• Sonogram before 24 weeks confirm dates
• Documentation of more than 18 weeks by fetoscope
  of FHT

Maternal- Fetal Medicine Textbook 2004
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Medications used in management of premature labour

• ß-sympathomimetic agents given to suppress
  uterine contractions and corticosteroids given to
  enhance fetal lung maturity.
• Following administration of salbutamol, there may
  be a rapid rise in blood glucose level
• Alternative tocolytic agents such as nifedipine
  are recommended.
• Following administration of corticosteroid, the
  rise in blood glucose level usually starts about
  612 hours later, and may persist for up to 5
  days
• BS level monitored every 12 hours until
  glycaemic control has stabilised

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Delivery

• Delivery should be at term unless obstetric or
  medical factors dictate otherwise (eg, fetal
  macrosomia, polyhydramnios, poor metabolic
  control, preeclampsia,IUGR).
• Vaginal delivery is preferable unless there is an
  obstetric or medical contraindication.
• Birthweight exceeds 42504500g warrants
  consideration of elective caesarean section.

MJA Volume 183 Number 7 3 October 2005
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Indication for delivery diabetic pregnancy

• Fetal Non reactive, Positive CST
  
• mature fetus
• Sonographic
  evidence of fetal growth arrest
• Decline in
  fetal growth rate with decreased amnionic
  
  fluid
• 40 41 w
  gestation
• Maternal Severe preeclampsia
• Mild
  preeclampsia, mature fetus
• Markedly
  falling renal function
• Obstetric preterm labor with failure of
  tocolysis
• Mature fetus ,
  inducible cervix

Maternal- Fetal Medicine Textbook 2004
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Thank you
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Fetal Monitoring

• Evaluations for neural tube defects and other
  congenital malformations begin with triple-screen
  testing at approximately 15 to 21 weeks of
  gestation.
• A fetal anatomic survey is performed at 18 weeks
  of gestation.
• Fetal echocardiography may be performed at 20 to
  22 weeks of gestation

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Cardiac evaluation

•   Indications for screening for CAD

women 35 years or older withe one or
more Hypertension (blood pressuregt
130/80mm Hg) , Smoking
Positive family history
Hypercholesterolemia (LDL gt100 mg/dL,HDL lt40
mg/dL) Renal disease
(microalbuminuria or nephropathy)
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Fetal Monitoring

• Ultrasound is used at 28 weeks of gestation to
  evaluate
• fetal growth and the quantity of amniotic fluid.
• Fetal surveillance,including nonstress test and
  biophysical profile as well as maternal
  monitoring of fetal activity is initiated in the
  third trimester to reduce the risk of
  stillbirth.

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labor and Delivery

• The method of delivery is based on the usual
  obstetric indications,as well as on fetal weight
  and the presence or absence of active retinal
  changes. Infants of diabetic mothers are more
  likely to be macrosomic.
• Cesarean sections are recommended for fetuses of
  an estimated weight greater than 4,500 g.
• It is important to maintain euglycemia during
  labor or prior
• to a scheduled cesarean section.

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Postpartum Management

• Insulin dosing should be titrated daily toward
  the preconception dose as necessary.
• Urine microalbumin, thyroid function, and HbAlc
• should be reevaluated.
• The American Academy of Pediatrics considers the
  ACEIs captopril and enalapril safe for use by
  the breastfeeding mother and are resumed in
  patients with nephropathy, microalbuminuria and
  hypertension .

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First trimester

• Same as preconception counseling care
• Evaluate risk factors

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Second trimester

• Visit the pt every 2 to 4 weeks or more if pt has
  complications or glycemic control is suboptimal .
• Maternal analyte screening screening for
  aneuploidy or neural tube defects ( a fetoprotein
  ,unconjucated estriol ,HCG,inhibin A )
• Diabetes does not increase the risk of fetal
  aneuploidy.
• Sonography at 18 weeks of gestation

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Third trimester

• Visit for every 1 to 2 weeks untile 32 wks of
  gestation then weekly
• Glycemic control
• Sonography
• Estimation of fetal size
• Surveillance for pregnancy complication
• Fetal surveillance weekly NST at 32 weeks with
  suboptimal HbA1C from 34 - 35 weeks with nl
  HbA1C two times per week from 36 weeks until
  delivery
• Assess for macrosomia ,premature labor ,
  hydramnious

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Fetal Surveillance

• The goals of management of diabetic pregnancy are
  to prevent stillbirth and asphyxia while
  minimizing maternal morbidity associated with
  delivery. This involves monitoring fetal growth
  in order to select the proper timing and route of
  delivery. The first is testing fetal well- being
  at frequent intervals and fetal size.

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Fetal Surveillance

• The priciple is to verify fetal viability in the
  first trimester
• Validate fetal structural integrity in the second
  trimester
• Monitor fetal growth during most of the third
  timester
• Ensure fetal well-bing in the late third
  trimester

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glycemic control plays an important role in
reducing the frequency of fetal and neonatal
complications.
(HbA1C values are useful in evaluating a woman's
glycemic control early in pregnancy.
One goal of preconception care of women with
diabetes is to evaluate glycemic control and
recommend adjustments in diet, medications, and
lifestyle, as needed, to achieve euglycemia.
Type 2 diabetics on oral anti-hyperglycemic
agents should be switched to insulin therapy
preconceptionally
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• Prepregnancy evaluation and counseling of women
  DM ? minimize the risk to the FM
• Women who are in poor glycemic control during the
  period of fetal organogenesis, which is nearly
  complete by seven weeks postconception, have a
  high incidence of spontaneous abortion and
  fetuses with congenital anomalies
• Thus, the importance of evaluating glycemic
  control in women with DM and achieving good
  glycemic control before conception cannot be
  overstated.

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The three major potential fetal/pregnancy
complications among women with pregestational
diabetes are congenital malformations,
spontaneous abortion, and macrosomia.

• Hyperglycemia is probably the most important
  determinant
• of these risks.
• This conclusion is supported by repeated
  observations that normalizing blood glucose
  concentrations before and early in pregnancy can
  reduce the risk of spontaneous abortion and
  congenital malformations to nearly that of normal
  women

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Management of women with diabetes before
conception

• Information and counselling should be provided to
  all women of reproductive age with diabetes
• A meta-analysis has demonstrated a significantly
  lower prevalence of major congenital anomalies in
  offspring of women who attended for prepregnancy
  counselling (relative risk, 0.36 95 CI,
  0.220.59 absolute risk, 2.1 v 6.5).

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Assessment of renal function

• Spot urine for microalbumin /cr or time
  collection for 24 hrs
• Serum cr
• Crgt 2mg/dl GFR lt 50 ml/min. proteinuria more
  than 2 gr /day can be considered relative
  contraindications to pregnancy

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Initial prepregnancy assessment should document
baseline renal function, include protein
excretion, serum creatinine, and creatinine
clearance

• The risk of permanent decline in renal function
  is substantially increased in women with a urine
  creatinine concentration above 2.0 mg/dL many of
  whom have more than 2 g of proteinuria per day.
• These findings can be considered relative
  contraindications to pregnancy.
• A creatinine clearance below 50 mL/min before
  pregnancy is associated with a high prevalence of
  hypertension and fetal wastage

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Preconception treatment goal

• Plasma
• FBS 80-110
• 2hpp 100-155
• HbA1C lt 7 normal if possible
• Avoid hypoglycemia

Joslin text book 2005
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Cardiac evaluation

• Testing may include one or more of the following
  
• electrocardiogram, echocardiogram, and exercise
• tolerance testing with the recognition that the
  resting
• electrocardiogram is the least sensitive of these
  tests.

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Thyroid disorders

•  Prepregnancy evaluation should include
  measurement of serum TSH

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Preconception counseling

• Education
• Maternal risk assessment

Fetal risk assessment
Metabolic goals should be established prior to
conception
Self-management skills should be reviewed.
Nutrition counseling to establish an
individualized meal plan should be provided.
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• Daily folic acid 1 mg prior conception
  continue after conception
• Mental health professional should be available
• A formal dilated funduscopic examination and
  clearance for pregnancy by an ophthalmologist

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Treatment of Diabetes during Pregnancy

• Home blood glucose monitoring is performed a
  minimum of four times daily,including before
  breakfast, 2 hours after meals, before
  driving,and with signs or symptoms of
  hypoglycemia.
• Premeal and middle-of-the-night testing may be
  necessary in some patients.
• First-void urine samples are tested for ketones.

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Insulin requirements what to expect

• Hypoglycaemia, especially overnight, is more
  frequent from the 6th to 18th weeks of gestation
• Insulin requirements can fall after 32 weeks
• Any fall greater than 510 should lead to an
  assessment of fetal wellbeing

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First trimester ultrasound examination

• First trimester US examination is often obtained
  to document viability
• As the rate of spontaneous abortion is higher in
  diabetic women
• and
• To assist in estimation of gestational age

Uptodate 2007
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Fetal assessment

• Screening for fetal anomalies should be done with
  first and second trimester
• ultrasound and a fetal echocardiogram between 20
  and 22 weeks gestation. As

Obstet Gynecol Clin N Am 31 (2004) 907 933
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• Fetal Risk

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Obstetric management

• US examination for fetal morphology should be
  offered at 1820 weeks.
• Further examinations to assess fetal growth
  should be performed at 2830 weeks and repeated
  at 3436 weeks.
• The latter will help to determine the timing and
  route of delivery.

MJA Volume 183 Number 7 3 October 2005