1. Obesity and Pregnancy Vanessa H. Gregg, MD Assistant Professor of OB/Gyn University of Virginia

2. Objectives  Review maternal complications of obesity in pregnancy  Review fetal/neonatal complications of obesity in pregnancy  Discuss long-term implications  Review practical issues in the management of obese pregnant women

3. Obesity in America  Greater than 60% of Americans are overweight (BMI 25 to <30)  Of those, half are obese, with a BMI of 30 or greater  In Virginia, 26% of residents are obese

4. Percent of adults who are obese in Virginia, 2008 http://apps.nccd.cdc.gov/DDT_STRS2/CountyPrevalenceData.aspx?mode=OBS

5. Defining Obesity  Overweight = BMI 25-29.9  Obesity:  Class 1 = BMI 30-34.9  Class 2 = BMI 35-39.9  Class 3 = BMI > 40

6. Obesity and Pregnancy  Increasing prevalence of obesity in pregnancy  Between 1993 and 2003 the rate of pre-pregnancy obesity increased 69%  Approximately 1 in 5 pregnant women in America is obese. Kim SYKim SY, Dietz PM, England L, Morrow B, Callaghan WM. Trends in pre-pregnancy obesity in nine states, 1993-2003.Dietz PMEngland LMorrow BCallaghan WM Obesity (Silver Spring).Obesity (Silver Spring). 2007 Apr;15(4):986-93.

7. Maternal Complications  Higher Rates of Cesarean Section  Gestational Hypertension  Pre-eclampsia  Gestational Diabetes  LGA and Shoulder dystocia  Stillbirth  DVT/PE  Anesthetic complications

8. Maternal Complications ComplicationBMI 19.8-26BMI 35-40BMI >40 Pre-eclampsia1.4%3.4% (OR 3.90)3.5% (OR 4.82) Cesarean section 10.9%21.5% (OR 2.32) 24.2% (OR 2.69) Shoulder dystocia 0.1%0.4% (OR 2.82)0.4% (OR 3.14) Large for gestational age OR 3.11OR 3.82 Cedergren, MI. Maternal Morbid Obesity and the Risk of Adverse Pregnancy Outcome. Obstet Gynecol, Vol 103, No 2. Feb 2004.

9. Risk of Cesarean Section  Increased risk due to:  Dysfunctional labor  Monitoring challenges  Increased rates of pre-eclampsia, hypertension and LGA babies all contribute to likelihood of cesarean section

10. Cesarean Section – Clinical Challenges  Access to lower uterine segment can be challenging  Higher rate of wound complications after surgery  Higher risk of anesthetic complications

11. Gestational Hypertension  Pre-existing hypertension is more common among obese women  Among those without hypertension at baseline, increased risk of developing gestational hypertension

12. Gestational Hypertension  Population-based study in the Netherlands  Increased rates of gestational hypertension among obese women (BMI >35), with odds ratio 4.67 Gaillard R et al. Associations of maternal obesity with blood pressure and the risks of gestational hypertensive disorders. Journal of Hypertension 2011, 29:937-944.

13. Gestational Hypertension: A UK population-based study  Among extremely obese women (BMI >50):  1 in 5 develop hypertensive disorder in pregnancy  1 in ten develop pre-eclampsia  Among women with less severe obesity, risk is increased but to a lesser degree Knight, M et al. Extreme Obesity in Pregnancy in the UK. Obstet Gynecol, Vol 115, No 5. May 2010.

14. Pre-eclampsia  Risk of pre-eclampsia is increased in obese pregnant women  Pre-eclampsia can lead to compromised fetal perfusion and to medically-indicated preterm birth.

15. Pre-Eclampsia  In same population-based study in Netherlands, increased risk of pre- eclampsia was observed for obese women (BMI >35), with odds ratio of 2.5. Gaillard R et al. Associations of maternal obesity with blood pressure and the risks of gestational hypertensive disorders. Journal of Hypertension 2011, 29:937-944.

16. Gestational Diabetes  Gestational diabetes is more common in obese pregnant women  In addition, there is a higher rate of pre-existing diabetes in obese pregnant women

17. Gestational Diabetes: A UK population-based study  Among extremely obese women, 11% developed gestational diabetes  Of those, 70% required insulin  Risk of developing diabetes was seven times higher than in non-obese controls  Among women with less severe obesity, risk is increased but to a lesser degree Knight, M et al. Extreme Obesity in Pregnancy in the UK. Obstet Gynecol, Vol 115, No 5. May 2010

18. Large for Gestational Age and Shoulder Dystocia  Maternal obesity predisposes to increased size of babies at birth.  Increased fetal adipose tissue, especially in the fetal abdomen, increases risk of shoulder dystocia  Shoulder dystocia carries additional morbidity to mother and baby.

19. Risk of Stillbirth  There is an increased risk of stillbirth associated with obesity  Risk of stillbirth increases with severity of obesity

20. Cohort Study of Rates of Stillbirth  One study of birth cohort in Missouri 1978-1997 examined >1.5 million births:  Obese mothers were 40% more likely to experience stillbirth Salihu, HM et al. Extreme Obesity and Risk of Stillbirth Among Black and White Gravidas. Obstet Gynecol 2007; 110:552-7.

21. Cohort Study of Rates of Stillbirth  There was significant racial disparity, with higher rates of stillbirth among black women than white women  Disparity widened with increasing BMI, with disproportionately highest stillbirth among extremely obese black women (BMI > 40). Salihu, HM et al. Extreme Obesity and Risk of Stillbirth Among Black and White Gravidas. Obstet Gynecol 2007; 110:552-7.

22. DVT/PE  Immobilization and pregnancy are both risk factors for DVT/PE  Obese pregnant women often have decreased mobility, particularly with extreme obesity  Cesarean delivery further increases the risk

23. Anesthetic Complications  Inability to establish regional block  Insufficient duration of regional block  Longer time to establish anesthesia  Refractory hypotension from anesthetic agents  Increased postdural puncture headache Vricella LK et al. Anesthesia Complications During Scheduled Cesarean Delivery for Morbidly Obese Women. Am J Obstet Gynecol 2010;203:276.e1-e5.

24. Fetal and Neonatal Complications  Stillbirth  Fetal Distress in Labor  Meconium Aspiration  Neonatal Death

25. Fetal and Neonatal Complications ComplicationBMI 19.8-26BMI 35.1-40BMI > 40 Stillbirth0.3%0.6% (OR 1.99)0.8% (OR 2.79) Fetal distress2.0%3.5% (OR 2.13)3.9% (OR 2.52) Meconium aspiration 0.1%0.3% (OR 2.87)0.3% (OR 2.85) Neonatal death0.1%0.3% (OR 2.09)0.4% (OR 3.41) Cedergren, MI. Maternal Morbid Obesity and the Risk of Adverse Pregnancy Outcome. Obstet Gynecol, Vol 103, No 2. Feb 2004.

26. Fetal and Neonatal Complications  As maternal BMI has risen, there has been a significant increase in the number of babies born with high birth weight.  Larger babies have more adipose tissue. Surkan PJ, Hsieh CC, Johansson AL, Dickman PW, Cnattingius S. Reasons for increasing trends in large for gestational age births. Obstet Gynecol 2004; 104: 720-6.

27. What happens later in life for children born to obese mothers?  Children born to obese mothers are twice as likely to be obese and develop type 2 diabetes in adult life.  Higher maternal gestational weight gain has been associated with high blood pressure in offspring. http://www.cdc.gov/reproductivehealth/MaternalInfantHealth/PregComplications.html

28. Contemplating the mechanism  One study showed an association between maternal BMI and the hepatic lipid content in the infants.  The increased lipid content in the liver may initiate programming of the metabolic syndrome in utero. Modi, N et al. The Influence of Maternal Body Mass Index on Infant Adiposity and Hepatic Lipid Content. Pediatric Research; Vol. 70, No. 3, 2011.

29. More Evidence: Early Menarche in Female Offspring  An NICHD study looked at age of menarche and found an association between maternal obesity and earlier menarche in female offspring.  There was also a correlation between maternal BMI and daughters’ BMI at age seven. Kleim SA, Branum, AM, Klebanoff MA, Zemel BS. Maternal Body Mass Index and Daughters’ Age at Menarche. Epidemiology. Vol 20, Number 5, Sept 2009.

30. Effects of Early Menarche  Early puberty is associated with  Glucose intolerance  Hypertension  Depression  Breast Cancer Kleim SA, Branum, AM, Klebanoff MA, Zemel BS. Maternal Body Mass Index and Daughters’ Age at Menarche. Epidemiology. Vol 20, Number 5, Sept 2009.

31. Optimal intrauterine growth affects long-term health  Inadequate and excessive fetal growth in utero both have the potential to predispose to the metabolic syndrome in adulthood.  Goal is “optimal” fetal growth, though this can be hard to define and achieve.

32. Optimal intrauterine growth affects long-term health Maternal Obesity Fetal Programming Offspring Obesity and Metabolic Syndrome

33. Practical Considerations  Increased utilization of healthcare resources  Difficult to use some of our routine prenatal surveillance tools  Increased hospital challenges

34. Utilization of Resources  Obesity in pregnancy is associated with:  Longer hospital stays  Greater use of health care services  More obstetric ultrasounds  More prescribed medications in pregnancy http://www.cdc.gov/media/pressrel/2008/r080402.htm

35. Clinic Challenges  Identifying fetal heart tones  Assessing fetal growth  Fundal height difficult to obtain  Assessing for hypertension  Blood pressure cuffs may be of inadequate size

36. Hospital Challenges  Monitoring  Anesthesia  Identifying epidural space  Airway protection  OR table limitations, surgeries technically more challenging  Increased risk of DVT due to immobilization

37. Strategies for Improvement  Will be discussed further in next talk  Institute of Medicine (IOM) provides weight gain guidelines by age.  Guidelines are not stratified by obesity classes.  May be that less weight gain is better, particularly for women with BMI above 40.

38. Summary  Increased rates of obesity in pregnancy have led to increasing complications for mother and baby  There are long-term consequences of obesity on future health outcomes  Obesity in pregnancy contributes to increased health care costs

39. Optimizing maternal pre- pregnancy weight and controlling gestational weight gain can have far-reaching consequences on future health of the population and on health care costs.