JENNIFER L W. FINK, RN, BSN

DIABETESIN PREGNANO

In addition to causingcomplications during pregnancy

and delivery, gestationaldiabetes can carry lasting

health risks for bothmother and child. Here's

how to keepshort- and long-term

problems at bay.

JENNIFER FINK, a former med/surgnurse, is a freelance writer and anindependent nursing consultant in

women's health in Mayville, WI. Theauthor has no financial relationships

to disclose.STAFF EDITOR: Jeff Bauer

Vol.69, No.^'-' www.rnweb.com

and beyondOnce viewed strictly as a complication of pregnancy, gestational diabetesmellitus (GDM) is now recognized as a complex metabolic condition thatcan present problems for mother and child later in life. Up to 9% of pregnantwomen develop GDM, and women who develop the condition during onepregnancy have a 50% - 70% chanceof being affected by the disease insubsequent pregnancies. '̂̂

These women also have a 30% - 50% chance ofdeveloping Type 2 diabetes later in life and face anincreased risk of suffering from cardiovascular dis-ease, hypertension, or stroke prematurely.^ Likewise,there are long-term implicahons for their children,who face an increased risk of diabetes and obesity inadolescence and adulthood.^

The good news, though, is that with early interven-tion, diligent monitoring, and disease management,GDM can usually be controlled and most, if not all, ofits adverse effects avoided. Your role in patient care,therefore, will be key.

Pregnancy and diabetes:Understanding the linkA complex interplay of hormones makes pregnantwomen particularly prone to hyperglycemia. Placen-tal lactogen, estrogen, and progesterone create insulinresistance, where the effectiveness of insulin in lower-ing the levels of blood sugar is diminished. Peripheralinsulin sensitivity—how well the body responds toinsulin—decreases and by the third trimester, it's onlyhalf of what it was in the first trimester.' At the sametime, basal hepatic glucose production increases,which increases blood glucose.^

Maternal insulin production typically increases tocompensate for these changes. But not all women pro-

duce enough insulin to meet the rising demand.Those who don't, develop GDM, defined as glucoseintolerance that begins or is first detected duringpregnancy.

Left untreated, gestational diabetes increases the riskof preeclampsia and preterm labor.' What's more, ex-cess glucose crosses the placental barrier and causesmacrosomia—excessive fetal growth. Women withGDM have an increased risk of a difficult, instrument-assisted delivery or a delivery by Cesarean section,usually because of the infant's size.

A vaginal delivery puts an infant with macrosomiaat risk for shoulder dystocia—a complication in whichthe baby's shoulder becomes stuck on the mother'spelvic bone. Shoulder dystocia can cause Erb's palsy,paralysis of the arm that usually resolves within a fewdays or weeks but in some cases may have lastingeffects.' More importantly, if the baby remains stuck,shoulder dystocia can lead to fetal hypoxia, and pos-sibly even death.'

Poor maternal glycemic control endangers the fetusin other ways, as well. GDM can cause intrauterinehypoxemia and placental insufficiency, resulting infetal polycythemia, an excess of red blood cells thatincreases blood viscosity and can lead to problemsboth before and after birth because the blood becomestoo thick. Newborns may also develop hypoglycemiaas a result of the excess insulin they produce duringgestation.'

Right after delivery, respiratory distress is a rarebut potentially serious complication.' An infant whosecretes excess insulin to deal with increased maternal

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glucose might experience delayedlung maturity, which increases hisrisk for respiratory distress.

Critical interventions hingeon knowing who's at risk

Successful treatment of GDM de-pends upon early detection andintervention. The earlier you inter-vene, the more time you'll have tohelp the mother maintain normalblood glucose levels and create ahealthier intrauterine environment.

Whenever you see a pregnantwoman, whether for a prenatalcheckup or any other reason,assess her risk factors for GDM.These include obesity, family his-tory of diabetes or GDM, previousdelivery of a baby who was largefor his gestational age, and poly-cystic ovarian syndrome.'

Ethnic background plays a role,too: GDM is up to 10 times moreprevalent among Native Americansthan it is among the general popu-lation."̂ African-Americans are one-and-a-half times more likely todevelop gestational diabetes thantheir Gaucasian counterparts. His-panics and Pacific Islanders alsohave an increased risk.'

Whether screening for the condi-tion should be selective or univer-

sal is subject to ongoing debate.The American Diabetes Associa-tion recommends selective screen-ing, excluding low-risk women—those with a normal pre-pregnancyweight, no ethnic risk factors, andno family history of diabetes orpersonal history of difficult preg-nancy.'•''

The American College of Obste-tricians and Gynecologists (ACOG)takes a different approach. Sincemost cases of GDM develop in thefifth or sixth month of pregnancy,ACOG recommends universalscreening at 24 - 28 weeks' gesta-tion.^ As a practical matter, an esti-mated 90% of obstetricians screenall their pregnant patients.*"

The 50 gm, one-hour glucosescreening test (GST), which mea-sures a patient's blood glucose lev-els an hour after she drinks a glu-cose solution, is the most widelyused method.'•'' Fasting isn't re-quired, and the test can be given atany time of day. Traditionally, ablood glucose level >140 mg/dLhas been the threshold for furtherinvestigation, but there's evidencethat using >130 mg/dL as the cutoffidentifies 10% more cases of GDM.''

If a patient exceeds the thresh-old being used, she will typicallyundergo a 100 gm, three-hour glu-

• Gestational diabetes mellitus increases a mother'sand child's risk of developing diabetes later in life.

• While about 85% of women with gestationatdiabetes can control it with diet and exercise,the remaining 15% need drug therapy.

• Regular blood glucose tests are recommendedfor anyone who has had gestational diabetes.

cose tolerance test (GTT). Here,blood glucose is measured afterthe patient fasts for eight to 14hours and again at one, two, andthree hours after she consumes100 gm of glucose.

A diagnosis of GDM requirestwo or more glucose values toexceed the criteria. Some cliniciansuse a fasting level >95 mg/dL, aone-hour level >180 mg/dL, a two-hour level >155 mg/dL, and athree-hour level >140 mg/dL as thethreshold.^ Others set the thresholdat 105, 190, 165, and 145 mg/dL,respectively.'

A diagnosis of GDM leadsto a focus on diet, exercise

To maintain tight control, awoman with GDM needs to eat abalanced diet, increase her physi-cal activity, and closely monitorher glucose levels, typically test-ing her blood by fingerstick imme-diately after waking in the mom-ing and after each meal. About85% of patients can achieve thetargets—before-meal levels of 80 -95 mg/dL and two-hour post-prandial levels of <120 mg/dL—with lifestyle changes alone.''^

To help make lifestyle changes areality, your GDM patient willneed to receive nutritional coun-seling from a registered dietitian.**While the optimal diet hasn't beendetermined, patients are generallyadvised to limit their carbohy-drate intake to 35% - 40% of theirtotal daily calories.**

Recommendations for total ca-loric intake are based on bodymass index. A pregnant woman ofnormal weight (BMI of 20 - 25)should consume 30 kcal/kg/day,underweight patients (BMI <20)should take in 35 - 38 kcal/kg/day, and overweight or obesepatients should restrict their in-

28 RN MAY 2006 Vol. 69, No. 5 www.rnweb.com

take to 20 - 25 kcal/kg/day>^Teach your patient that to sus-

tain steady blood glucose levels,she should divide her daily intakeinto three main meals supple-mented by three or four snacks.^Her dietitian can help her create arealistic, culturally appropriateeating plan.

Encourage your patient to exer-cise regularly, too, and point outthat even moderate exercise willlower her blood glucose levels."Tell her to consult her physician,who will determine how muchand how intensely she can exer-cise without increasing her risk ofpreterm contractions."

Walking for 20 - 30 minutesthree or four times a week may bethe easiest, and most widely rec-ommended, exercise for pregnantwomen.^ But no matter what activ-ity your patient engages in, stressthe need to stop immediately andcall the doctor if she experiencesdizziness, pain, or contractionswhile exercising.^

Make sure your patient can rec-ognize the signs and symptoms oflow blood sugar—sweating, ner-vousness, shakiness, weakness,extreme hunger, slight nausea,dizziness, headache, and blurredvision—and tell her to keep low-fat milk, fruit juice, candy, or otherquick-sugar foods readily avail-able. Tell her that if she developsthese symptoms, she should eatone of these foods first and thencall her healthcare provider.

Support is also a crucial compo-nent of your nursing care. Listeningto your patient's concerns andemphasizing your desire to help cango a long way toward alleviatingthe anxiety that typically accompa-nies a diagnosis of gestational dia-betes. Assess her stress level andcoping techruques. Determine whatsupport systems are available for

A collaborative diabetes programspells ''Sweet SuccessBecause gestational diabetes mellitus affects many aspects of a woman'slife, the most effective programs are interdisciplinary. Ideally, they shouldinclude nurses, physicians, dietitians, and social workers, collaborating toprovide individualized support and education.

One program that takes such collaboration to heart is Sweet Success,which operates within the framework of a larger government-fundedinitiative called the California Diabetes and Pregnancy Program. CDAPPis primarily a nurse-ied interdisciplinary initiative that divides the state

into regions. Each region has acoordinator, nurse educator, dietitian, andbehavior medicine specialist who providestraining and resources to clinical sitesaffiliated with the Sweet Success program.

Women are referred to a Sweet Successaffiliate by their primary care provider.Because the program uses consistentguidelines for screening and treatment,the women get top-notch care early inpregnancy. Nurse educators, registereddietitians, and behavior medicinespecialists provide individual counseling.And each patient has frequent contact witha nurse who monitors blood glucose levelsvia fax and phone at least every two weeks

and as often as every day, if needed. The cost for this care is covered bythe woman's insurance.

As the name suggests. Sweet Success has been extremely effective sinceits inception more than 20 years ago. An analysis by CDAPP found thatthe program has decreased both maternal and neonatal morbidity,including preterm deliveries, macrosomia, birth defects, NICUadmissions, and maternal admissions for diabetes control.

Sweet Success affiliates report that they cared for more than 17,000women in 2004. The Sweet Success model has spread beyond California,with similar programs in at least 38 states. To find out if there's a programnear you, call the Sweet Success resource center at (858) 536-5090 or visitwww.llu.edu/llumc/sweetsuccess.

Sources: 1. California Diabetes and Pregnancy Program. "Sweet Success."www.liu.edu/llumc/sweetsuccess/ (21 Feb. 2006). 2. Sweet Success ExtensionProgram. "SSEP: A nonprofit corporation tact sheet." www.sweetsuccessexpress.com/factsheet.htmi (21 Feb. 2006).

your patient, and make appropriatereferrals, if necessary.

Is your patient a candidatefor drug therapy? ^

Because GDM typically isn't diag-nosed until the fifth or six month ofpregnancy, there's a small windowof opportunity for intervention. Asa result, many clinicians prescribe

drug therapy if a two-week dietand exercise regimen fails toachieve target glucose levels.

Insulin is the only FDA-approved treatment for GDM, butsome patients have had goodresults with oral hypoglycemics,particularly glyburide {Diabeta,Glynase, others) and metformin(Glucophage, Glumetza).''''" Theyare much easier to store and ad-

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minister than SQ insulin, andmany women prefer them.''

In clinical trials, women takingglyburide have had pregnancyoutcomes comparable to those oninsulin—with fewer hypoglycemicepisodes.^'" And glyburide costsconsiderably less/ Metformin hasnot been studied as extensively.Initial results of a large, multina-tional trial are promising, but fur-ther research is needed to assessthe long-term risks of fetal expo-sure to this drug.

It's important to remember thata woman's insulin requirementschange throughout pregnancy.Patients with GDM generally re-quire higher doses of insulin thanpatients with Type 1 diabetes whoaren't pregnant.^ Frequent bloodglucose monitoring is necessary todetermine the dosages and timingof the insulin regimen.^

Keeping a close eyeon fetal growthFor women who manage to controlGDM with diet and exercise, rou-tine prenatal care—along with reg-ular blood glucose testing—is suf-ficient.' For those who requiredrug therapy, however, more in-tensive fetal monitoring is recom-mended.' The purpose, of course,is to prevent fetal compromise andstillbirth by detecting any abnor-mahties and intervening as needed.

Many clinicians perform weeklyor biweekly non-stress tests start-ing at 32 weeks' gestation.''' Somealso recommend lung maturitytesting as well as ultrasound to de-tect macrosomia, but ultrasound re-sults for fetal weight aren't alwaysaccurate.''^ If the physician ordersany of these prenatal tests, carefullyexplain what's being done andwhat each test may reveal.

The vast majority of women

with GDM have an uncomplicatedvaginal delivery at between 37 and42 weeks' gestation. There's no evi-dence that intervention is neces-sary before 41 or 42 weeks if thefetus is of normal weight and thepregnancy is progressing withoutdifficulty.''' Elective delivery mightbe considered, though, if the fetalweight exceeds 4,000 gm or themother has poor glycemic control,vasculopathy-related hypertension,or a history of stillbirth.^

Immediately postpartum, infantsof women with GDM face the riskof hypoglycemia and respiratorydistress. Hypoglycemia usually re-solves when the baby is fed, but aninfant who's symptomatic mayneed 10% dextrose administeredrV.' Monitor the baby's blood glu-cose every hour until it stabilizes.

Respiratory distress is the mostserious complication. An infantwhose respiration is compromisedmay need supplemental oxygen,ventilatory support, and surfac-tant replacement until he canbreathe on his ^

Postpartum follow-upis especially importantBecause GDM is a risk factor fordiabetes for both mother andchild, follow-up testing is essen-tial. The ADA recommends thatwomen undergo a two-hour, 75 gmGTT at their six-week postpartumcheckup.^ A patient whose resultsshow impaired glucose toleranceneeds to be reminded of the im-portance of continuing the life-style changes she made whilepregnant and undergoing annualtesting. If her levels at six weeksare normal, she should be testedonce every three years.

There are no standards for fol-low-up of a child born to a womanwith GDM.' However, given the

child's heightened risk of diabetesand obesity in adolescence andadulthood, you'll need to makesure his pediatrician knows themother had GDM and encouragethe mother to share this informa-tion with all future healthcareproviders.

Today it's clear that GDM isanything but a simple complica-tion of pregnancy. In years tocome, we may learn even moreabout the role of GDM in thedevelopment of adult-onset dis-eases, including diabetes, obesity,and cardiovascular disease. Fornow, we can continue to interveneand improve outcomes, one fam-ily at a time. RN

h REFERENCES H

1. Hicks, P. "Gestational diabetes in pri-mary care." 2000. www.medscape.com/viewarticle/408910 (24 Feb. 2006).2. Crowther, C. A., Hiller, J. E.. et al.(2005). Effect of treatment of gestationaldiabetes mellitus on pregnancy out-comes. N EngI J Med. 352(24), 2477.3. Centers for Disease Control and Pre-vention. "Diabetes & women's healthacross the life stages." 2001. www.cdc.gov/diabetes/pubs/pdf/women.pdf (24Feb. 2006).4. American Diabetes Association. (2006).Standards of medical care in diabetes—2006. Diabetes Care. 29(S1), S7.5. American College of Obstetricians andGynecologists. "Gestational diabetes."2001. www.guideline.gov/summary/summary.aspx?ss-15&doc_id-3979&nbr-3118 (27 Feb. 2006).6. Waiiing, A. D. "ACOG update on gesta-tional diabetes mellitus." 2002. www.aafp.org/afp/20020301/tips/20.html (27 Feb.2006).7. Langer, C. (2005). Current manage-ment of diabetic pregnancy. OBG Man-agement. 77(10), 16.8. American Diabetes Association. (2004).Gestational diabetes mellitus. DiabetesCare. 24{S^). S88.9. American Academy of Family Physicians."Gestational diabetes: What it means forme and my baby." 2005. http://familydoctor.org/075.xml (27 Feb. 2006).10. Slocum, J. M., & Burke Sosa, M. E.(2002). Use of antidiabetes agents inpregnancy: Current practice and contro-versy. J Perinat Neoriatal Nurs, J6(2), 40.

30 RN MAY 2006 Vol. 69, No. 5 www.rnweb.com

Circle theSave this

RN/Thomson AHC Home Study Program

Continuing Education Test #1067"Diabetes in pregnancy and beyond"

ijjjuj OBJECTIVES After reading the articie you should be able to:

^ 1. Describe the physiological changes that result in gestational diabetes mellitus (GDM}.2. Describe how GDM affects the mother and fetus.3. Develop a teaching plan for the woman with GDM.

one best answer for each question below. Transfer your answers to the card that follows page 40.sheet to compare your answers with the explanations you'll receive. Or, take the test online at www.rnweb.com.

1. All of the following hormonal changesthat occur during pregnancy canmake women prone to hyperglycemiaEXCEPT:a. Peripheral insulin sensitivity decreases.b. Basal hepatic glucose production

increases.c. Ptacental lactogen decreases insulin

resistance.d. Placental estrogen and progesterone

create insulin resistance.

Gestational diabetes mellitus (GDM)is defined as glucose intolerance that:a. Begins or is first detected during

pregnancy.b. Begins during the first trimester and

continues throughout the pregnancy.c. Begins during the second trimester and

continues throughout the pregnancy.d. Is present and well-controlled prior to

pregnancy but becomes difficult tocontrol duting pregnancy.

3. Untreated GDM can result in all of thefollowing EXCEPT an increase in therisk of:a. Preeciampsia.b. Preterm iabor.c. A breech delivefy.d. A Cesarean delivery.

Patients wrth GDM are generallyadvised to limit carbohydrate intaketo what percentage of their totaldaily calories?a. 15%-20%.b.22%-26%.c. 28% - 33%.d. 35% - 40%.

Poor maternal glycemic control canresult in intrauterine hypoxemia andplacental insufficiency, endangeringthe fetus by causing:a. Poiycythemia.b. Pancytopenia.c. Hyperglycemia.d. Hypothyroidism.

6. Right after delivery, the most seriousrisk to the newborn is:a. Bleeding.b. Polycythemia.c. Hyperglycemia.d. Respiratory distress.

7. Women who develop GDM duringone pregnancy have what chanceof developing it in subsequentpregnancies?a. 10%-20%.b.20%-40%.c. 30%-50%.d. 50% - 70%.

8. Women who develop GDM duringone pregnancy have what chanceof developing Type 2 diabetes laterin life?a. 10%-20%.b. 20% - 30%.c. 30% - 50%.d. 50% - 70%.

9. Women who develop GDM are atincreased risk for alt of the followingEXCEPT:a. Stroke.b. Glaucoma.c. Hypertension.d. Cardiovascular disease.

10. Risk factors for GDM include allof the following EXCEPT:a. Obesity.b. Under 20 years of age.c. Famiiy history of diabetes.d. Polycystic ovarian syndrome.

11. GDM rs 10 times more prevalent in:a. Asians.b. Hispanics.c. Native Americans.d. African-Americans.

12. Up to what percentage of pregnantwomen develop GDM?a. 9%.b.11%.c. 13%.d. 15%.

13. The American College of Obstetriciansand Gynecologists recommendsuniversal screening for GDM at:a. 12 - 16 weeks' gestation.b. 18 - 22 weeks' gestation.c. 24 - 28 weeks' gestation.d. 30 - 34 weeks' gestation.

14. During a vaginal delivery, infants withmacrosomia are at high risk for:a. Hemangiomas.b. Meccnium stool.c. Shoulder dystocia.d. Cord stranguiation.

15. Which threshold level of blood glucosehas been shown to identify the mostcases of GDM?a. 125 mg/dLb. 130 mg/dLc. 135 mg/dL.d. 140 mg/dL

16. To maintain tight control of GDM,before-meal target levels of bloodglucose should be:a. 60 - 75 mg/dL.b. 80 - 95 mg/dL.c. 100-115 mg/dLd. 120-130 mg/dL

17. To sustain steady blood glucoselevels, a woman with GDM shoulddivide her daily food intake into:a. Two main meals supplemented by three

or tour snacks.b. Two main meals supplemented by five

to seven snacks.c. Three main meals supplemented by one

or two snacks.d. Three main meals supplemented by

three or four snacks.

18. The American Diabetes Associationrecommends women with GDM havewhich study done at the six-weekpostpartum checkup?a. Hemoglobin A1C.b. Fasting blood sugar level.c. 50 gm one hour glucose screening test.d. 75 gm two-hour glucose toierance test.

Thomson American Heafth Consultants is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's Commissich onAccreditation. AHC is approved as a provider by the Caiifcmia Board of Registered Nursing (provider number CEP 10864). This activity is approved for 1 nursingcontact hour. This activity has been approved by the American Association of Critical-Care Nurses tcr 1 nursing ccntact hour (Category A credit). Credit will begranted for this unit through May 2008. It was prepared by Anne Robin-Waldman, RN, BC, MSN, AOCN.

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