Nutricion en el embarazo de las clinicas de norteamerica

Obstet Gynecol Clin N Am 35 (2008) 369–383

Nutrition During Pregnancy
Jean T. Cox, MS, RD, LN*, Sharon T. Phelan, MD, FACOG
Department of Obstetrics & Gynecology, University of New Mexico, MSC 10 5510, 1 University of New Mexico, Albuquerque, NM 87131, USA

Nutritional issues in pregnancy have gained greater importance in routine prenatal care as obesity issues, low birth weight (LBW)concerns, and neural tube defect (NTD) prevention strategies have moved into the forefront of prevention measures. A discussion of nutritional considerations in pregnancy can be organized as weight gain, specific nutrients, and special patient groups relative to dietary concerns.

Prenatal weight gain issues Pregnancy weight gain goals were set by the Institute of Medicine (IOM) in 1990 [1]. The goalat the time was to optimize pregnancy outcome (ie, fullterm delivery of a healthy baby weighing 3 to 4 kg). An attempt was made to balance the needs of mother and baby, but ‘‘at that time, there was insufficient data available to conclude whether the higher gestational weight gains would result in increased maternal body weight or influence the risk of becoming overweight’’ [2]. Weight gain goalsare based on the mother’s prepregnant body mass index (BMI) and are summarized in Table 1. Prepregnant weight is her actual weight just before this pregnancy or at the first prenatal visit, if it is early. If care is late and no reliable estimate of prior weight exists, one should assume she has gained appropriately and go from there. Underweight women overestimate their prepregnant weight, butoverweight women underreport their weight, especially if they have less than a high school education [1,3]. The discrepancy is worse as the degree of overweight increases [3]. Height also needs to be measured, not asked. People tend to

* Corresponding author. E-mail address: jcox@salud.unm.edu (J.T. Cox). 0889-8545/08/$ - see front matter Ó 2008 Elsevier Inc. All rights reserved.doi:10.1016/j.ogc.2008.04.001 obgyn.theclinics.com

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Table 1 Institute of Medicine prenatal weight gain goals Body mass index Normal Underweight Overweight Obese Twins 19.8–26.0 !19.8 O26.0–29.0 O29.0 Ignore Total weight gain (lb) 25.0–35.0 28.0–40.0 15.0–25.0 R15.0 35.0–45.0 Total weight gain (kg) 11.5–16.0 12.5–18.0 7.0–11.5 R6.0 16.0–20.5

The IOM also states that young adolescents (!2years postmenarche) and black women should strive to gain toward the upper end of the ranges. Shorter women (!157 cm or 62 in) should strive to gain toward the bottom of the range. Data from Institute of Medicine, Subcommittee on Nutritional Status and Weight Gain During Pregnancy. Nutrition during pregnancy: part I, weight gain, part II, nutrient supplements. Food and nutrition Board, Instituteof Medicine, National Academy of Sciences, National Academy Press, Washington, DC, 1990.

overestimate height, especially if they have little formal education [1] or if they are short or overweight [3]. Both LBW and very low birth weight (VLBW) rates are higher for women whose prepregnant weight is outside the normal category [4], and they are made worse if gestational weight gain is inadequate.Prepregnant underweight is associated with a higher risk for preterm delivery and for a small for gestational age (SGA) baby [5]. Prepregnant obesity provides particular concerns [6–8]. Obesity rates in the United States are rising and it is estimated that one third of adult women are now obese, with rates higher among non-Hispanic black women and Mexican American women. The prevalence of women inthe United States weighing at least 250 pounds at entry to prenatal care rose from 2% in 1980 to more than 10% in 1999 and those at least 300 pounds rose to more than 4% [9]. Polycystic Ovary Syndrome prevalence and miscarriage rates are higher among obese women [6,7,9]. Fetal anomalies occur more often, even controlling for diabetes, and NTD rates are double those of babies of normal-weight...