CityMatCH / NACCHO Emerging Issues in Maternal and Child Health Conference Call

Impact of Healthy Weight in Mothers on Birth Outcomes

August 19, 2004

Siobhan Dolan, MD, MPH

Assistant Medical DirectorMarch of Dimes Birth Defects Foundation, White Plains, NY

Assistant Professor of Obstetrics & Gynecology and Women’s Health Albert Einstein College of Medicine, Bronx, NY

sdolan@marchofdimes.com 914-997-4788

1991 1995

2002

Obesity Trends Among U.S. AdultsBRFSS, 1991-2002

No Data <10% 10%–14 15%–19% 20%–24% > 25%

%

Ob

ese

*Based on self-reported weight and heightMokdad et al., JAMA 282:1519, 1999; JAMA 289, 76, 2003

Obesity* among US Adults,1991 and 2001

20.9

12

0

5

10

15

20

25

1991 2001

Overweight (BMI 25-

29.9)22%

Under/Average Weight

(BMI < 25)56%

Obese(BMI >= 30)

22%

Prevalence of Obesity and Overweight Among US Women, age 20-39, 1999-2002

Data from the National Health and Nutrition Examination Survey (based on actual

measurement of height and weight)

Hedley et al., JAMA 291: 2847, 2004

Overweight 25.4%

Overweight 25.4%

Obese 29.1%

Under/ Average Weight 45.5%

9.510.7

12.1

10.1

7.6

0

2

4

6

8

10

12

14

1982 1992 2002 2007 2010

Preterm BirthsPreterm BirthsUnited States, 1982-2002United States, 1982-2002

Preterm is less than 37 completed weeks gestation.

Source: National Center for Health Statistics, final natality data

Prepared by March of Dimes Perinatal Data Center, 2004

Percent

Healthy People Objective

March of Dimes Objective

27 Percent Increase

Risk Factors for Preterm Labor/Delivery• The best predictor of having a preterm birth is multifetal

gestation or history of preterm labor/delivery • Other risk factors:

–multifetal pregnancy

–maternal age (<17 and >35 years)

–black race

–low SES

–unmarried

–previous fetal or neonatal death

–3+ spontaneous losses

–uterine abnormalities

–incompetent cervix

–genetic predisposition

–low pre-pregnant weight

–obesity

–infections

–bleeding

–anemia

–major stress

–lack of social supports

–tobacco use

–illicit drug use

–alcohol abuse

–folic acid deficiency

Preterm Births (<37 weeks)by Maternal Race/Ethnicity, US, 2001

11.0

17.5

13.2

10.311.4 11.9

0

6

12

18

White Black NativeAmerican

Asian orPacific

Islander

Hispanic All Races

Percent

Preterm is less than 37 weeks gestation

Hispanics can be of any race

Source: National Center for Health Statistics, 2000 final natality data

Prepared by March of Dimes Perinatal Data Center, 2002

Prevalence of Overweight and Obesity Among US Women Aged 20-39 Years, 1999-2002, By Racial/Ethnic Group

01020304050607080

Overweightand Obese(BMI>=25)

Obese(BMI>=30)

Perc

en

t of

Wom

en

Non-HispanicWhite

Non-HispanicBlack

Mexican-American

Hedley et al., JAMA 291: 2847, 2004

What is the Impact of Healthy Weight in Mothers

on Birth Outcomes?

What is the impact of obesity and overweight on birth outcomes?

What is the impact of underweight on birth outcomes?

Body Mass Index (BMI) is an indicator that measures weight for height.

Body Mass Index (BMI)

The American Formula for Calculating BMI

BMI = ( ) X 703Weight in Pounds

(Height in inches) x (Height in inches)

Source: National Center for Chronic Disease Prevention and Health Promotion, CDC

Body Mass Index (BMI)

The BMI calculator is available online at: www.cdc.gov/nccdphp/dnpa/bmi/calc-bmi.htm

Example:

A woman who weighs 140 lbs and is 5 ft 6 in tall has a BMI of 22.6 - Normal

A women who weighs 140 lbs and is 5 ft 2 in tall has a BMI of 25.6 - Overweight

For adults over 20 years old

BMI Weight Status

Below 18.5 Underweight

18.5 – 24.9 Normal

25.0 – 29.9 Overweight

30.0 and Above Obese

Body Mass Index (BMI)

Height inches

20 25 30 35

60 102 128 153 179

64 116 145 174 204

68 131 164 197 230

72 147 184 221 258

weight in pounds

BMI

Adverse Outcomes Associated with Maternal Obesity

• Infertility• Maternal complications• Fetal, neonatal death• Labor and delivery complications• Birth weight/prematurity• Psychomotor development• Congenital malformations

0

1

2

3

4

5

Gestationaldiabetes

Preeclampsia Eclampsia

Ad

juste

d O

dd

s R

ati

o

Normal (BMI 20.0-24.9)

Overweight (BMI 25.0-29.9)

Obese (BMI >= 30.0)

Adjusted* Odds Ratios for Pregnancy Complications by Maternal BMI

Baeten et al., Am J Public Health 91;436, 2001

*Adjusted for maternal age, smoking, education, marital status, trimester prenatal care began, payer, and weight gain during pregnancy; BMI<20.0 (lean) reference group

Maternal Morbid Obesity and Risk of Adverse Pregnancy Outcome

• Prospective population-based cohort study in Sweden 1992-2001

• Maternal height and weight recorded in early pregnancy on 805,275 women

• Perinatal outcome of singletons born to women without insulin-dependent diabetes mellitus evaluated

Cedergren, Obstet Gyn 103:219, 2004

• Large numbers of obese women

– 69,143 with mild obesity (BMI 29.1-35)

– 12,698 with moderate obesity (BMI 35.1-40)

– 3,480 with morbid obesity (BMI> 40)

• Normal weight category (BMI 19.8-26) used as referent

• Maternal age, parity, smoking, year of birth, and maternal education included as covariates

Cedergren, Obstet Gyn 103:219, 2004

Maternal Morbid Obesity and Risk of Adverse Pregnancy Outcome

0.0

1.0

2.0

3.0

4.0

Preeclampsia Abruptioplacenta

Placentaprevia

Stillbirth > 28weeks

Ad

juste

d O

dd

s R

ati

o

MildModerateMorbid

Antenatal Complications by Degree of Maternal Obesity

Cedergren, Obstet Gyn 103:219, 2004

0.0

1.0

2.0

3.0

4.0

CesareanDelivery

Shoulderdystocia

Postpartumhemorrhage

LaborInduction

Ad

justed

Od

ds R

atio

MildModerateMorbid

Labor and Delivery Complications by Degree of Maternal Obesity

Cedergren, Obstet Gyn 103:219, 2004

0.0

1.0

2.0

3.0

4.0

Meconiumaspiration

Fetal distress Low Apgarscore

Earlyneonatal

death

Ad

justed

Od

ds R

atio

MildModerateMorbid

Neonatal Outcomes by Degree of Maternal Obesity

Cedergren, Obstet Gyn 103:219, 2004

0.0

1.0

2.0

3.0

4.0

SGA LGA

Ad

justed

Od

ds R

atio

MildModerateMorbid

Odds for SGA or LGA Infant by Degree of Maternal Obesity

Cedergren, Obstet Gyn 103:219, 2004

0.0

1.0

2.0

3.0

4.0

< 37 weeks at 42 weeks

Ad

justed

Od

ds R

atio

MildModerateMorbid

Odds for Pre-/Post-term Infant by Degree of Maternal Obesity

Cedergren, Obstet Gyn 103:219, 2004

Fetal and Neonatal Death by Maternal BMI

0

1

2

3

Normal Overweight Obese

Pre-pregnancy BMI

Od

ds R

ati

o

Late Fetal Death

Early Neonatal Death

Cnattingius et al., N Engl J Med 338:147, 1998

Reference group – Lean (BMI < 20)

50

75

100

Generalintellectual

ability

Differentialability non-

verbal

Differentialability verbal

Me

an

ps

yc

ho

mo

tor

sc

ore Underweight

(BMI<19.8)

Normal (BMI19.8-26.0)

Overweight(BMI 26.1-29.0)

Obese(BMI>29.0)

Mean Psychomotor Scores by BMI

Neggers et al., Acta Obstet Gynecol Scand 82:235, 2003

**

**

**

*p=0.006, **p=0.004Adjusted for birth weight, gestational age, age, home environment, preschool status, mother’s receptive

language ability, age, smoking and alcohol intake, and zinc supplementation

Risk for Birth Defects

1.8 1.9 1.9 2.0

1.4

1.9 1.8 1.7

0.0

1.0

2.0

3.0

4.0

Waller etal., '94

Shaw etal., '96

Watkinset al.,

'96

Werler etal., '96

Kallen, '98

Shaw etal., '00

Shaw etal., '00

Hendrickset al.,

'01

Od

ds

Ra

tio

Studies of Maternal Obesity and NTDs

Birth Defects Associated with Maternal Obesity

• Neural tube defects• Heart defects• Ventral wall defects• Multiple congenital anomalies• Cleft lip +/- palate?

Possible Dose-Response Relationship between Maternal BMI and Risk for Birth Defects

Watkins et al., Pediatrics 111:1152, 2003Watkins et al., Pediatrics 111:1152, 2003

Odds Ratio per Incremental Unit Increase in BMI for Women

of Average Weight or Heavier was1.08 (95% CI: 1.03-1.10, p=0.0001)

Possible Mechanisms

• Increased nutrient requirement (e.g., folate) among obese women

• Metabolic abnormalities associated with obesity• Hyperglycemia

• Elevated insulin levels

• Elevated estrogen levels

• Elevated lipid levels

• Undiagnosed diabetes

• Nutritional deficits in obese women (e.g., related to dieting behaviors)

Recommendations

WEIGHT MATTERS !!!

For your health and the health of your children

Weight Matters During Preconception Care

• Counsel women about increased risks

• Encourage assessment of BMI (CDC website) and weight loss when needed:– Balanced diet, Folic acid– Exercise

• Screening for hypertension and diabetes mellitus recommended

Weight Matters During Prenatal Care

• Counsel women about increased risks

• Discuss recommended weight gain during pregnancy

• Discuss healthy exercise and nutrition options during pregnancy

• Discourage dieting during pregnancy

• Screen for hypertension and diabetes as recommended

Institute of Medicine 1990Recommendations for Weight Gain

in Pregnancy

BMI Description Weight Gain

<19.8 Underweight 28-40 lb

(12.7-18.2 kg)

19.8-26.0 Normal 25-35 lb (11.4-15.9 kg)

26.1-29.0 Overweight 15-25 lb (6.8 lb 11.4 kg)

>29.0 Obese >15 lb (>6.8 kg)

This is not recommended!

Exercise During Pregnancy: ACOG Guidelines

• In the absence of either medical or obstetric complications, >= 30 minutes of moderate exercise on most, if not all, days of the week is recommended

• Exercise may be beneficial in primary prevention of gestational diabetes

• Exercise may be “a helpful adjunctive therapy” for gestational diabetes mellitus when euglycemia is not achieved by diet alone

ACOG Committee Opinion No. 267, Obstet Gynecol 99:171, 2002

Other Recommendations

• Ensure adequate intake of micronutrients (particularly iron and folic acid) – unknown if higher dose of folic acid helpful

• Abstain from smoking and alcohol use• Get adequate exercise• Encourage breastfeeding

Special Thanks

Sonja A Rasmussen, MD, MSSonja A Rasmussen, MD, MSNational Center on Birth Defects and National Center on Birth Defects and

Developmental Disabilities, CDC, AtlantaDevelopmental Disabilities, CDC, Atlanta