Weight Until You Read This!

by Michele Brown

pregnant woman on scalesIt's your prenatal check up day and everything is fine until the OBGYN's assistant requests that you "jump" on the scale. You cover your eyes and try not to look at the numbers, but you know the lecture is coming. You know you have gained too much even though you are pregnant and are supposed to gain weight. It's just not fair! Why are they harassing you over a few pounds?

This is why. The obesity epidemic in the United States, affecting males and females, all ages, and all ethnic groups has reached astronomic proportions in the last twenty years. It has been estimated that nearly two-thirds of adults are overweight and at least one-third of those are obese.

In pregnancy, being overweight or obese is especially concerning because of the increased association with pregnancy complications and adverse perinatal outcomes. BMI (body mass index) calculated from a persons weight and height is the value used to describe a person's fat distribution. Increased pregnancy risks are associated both with higher maternal pre-pregnancy BMI and also change in BMI category during the pregnancy. Being overweight or obese during pregnancy can also set the pattern to the development of obesity in midlife with all the added risks.

The guidelines that were established for gestational weight gain by the Institute of Medicine in 1990, specify that normal weight women (19.8–26.0 kg/m2) should gain 25–35 pounds during their pregnancy. Overweight is defined as weight (kg)/height squared (m) or BMI of 25 to 29.9 and obesity is BMI over 30. Studies have shown that more than half of all pregnant women don't fall within the current IOM guidelines and are therefore increasing their risks of complications both during and after their pregnancy.

What are some of the risks to a pregnant obese woman?
[Editor's note: Some question whether obesity itself or typical management protocols used on obese women cause certain complications.]

  • gestational diabetes
  • preterm delivery
  • preeclampsia
  • eclampsia
  • infections -- wound, endometritis, and chorioamnionitis
  • cephalopelvic disproportion or failure to progress in labor
  • lacerations
  • operative vaginal delivery (forceps)
  • cesarean section
  • failed induction
  • 2 to 3 fold increased risk of being overweight in midlife with the numerous chronic health problems (heart disease, hypertension, diabetes, stroke, gallbladder disease, certain cancers, osteoarthritis, dyslipidemia)

What are some of the risks to the baby of a pregnant obese woman?

  • birth defects
  • low 5 minute apgar scores
  • need for resuscitation at birth
  • stillbirth
  • macrosomia (greater than 4000 grams)
  • hypoglycemia
  • childhood obesity
  • longer nursery stays
  • risk of late fetal death
  • 2 fold increased risk of death within the first year of life


Interventions to prevent excessive weight gain in pregnancy may have to begin prior to a woman conceiving. The importance of educating a woman during her pregnancy about appropriate weight gain and the clinical implications of changing BMI status during pregnancy is paramount because of the association with poor gestational outcomes. Close monitoring of BMI with charting during pregnancy and added dietary counseling from health care providers for women exceeding the guidelines could help reduce perinatal mortality. Adhering to the Institute of Medicine guidelines results in lower perinatal risks.

Women who fail to lose weight after their pregnancy are more prone to weight issues and higher BMIʼs in midlife.




<19.8 (low) 28–40
19.8–26.0 (normal) 25–35
26.1–29.0 (high) 15–25
29.0 (obese) At least 15 pounds

So, now you know why weight gain must be controlled during pregnancy and why you should reach for apples instead of the cookies.

Dr. Brown, founder of Beauté de Maman, is a board-certified member of the American College of Obstetrics and Gynecology, a member of the American Medical Association, the Fairfield County Medical Association, Yale Obstetrical and Gynecological Society and the Women's Medical Association of Fairfield County. She is a magna cum laude graduate of Tufts University, completed her medical training at George Washington University Medical Center and completed her internship and residency in obstetrics and gynecology at Yale-New Haven Hospital. Dr. Brown has a busy obstetrical practice in Stamford, Connecticut and, as a clinical attending, actively teaches residents from Stamford Hospital and medical students from Columbia Presbyterian Hospital in New York.

Copyright © Michele Brown. Permission to republish granted to Pregnancy.org, LLC.