Objective
The purpose of this study was to determine the information that pregnant women report receiving when being counseled about weight gain and the risks of inappropriate gain.
Study Design
With the use of a self-administered questionnaire at prenatal clinics in Hamilton, Ontario, Canada, a cross-sectional survey was conducted of women who had had at least 1 prenatal visit, who could read English, and who had a live singleton gestation.
Results
Three hundred ten women completed the survey, which was a 93.6% response rate. Although 28.5% (95% confidence interval, 23.5–33.6%) reported that their health care provider had made a recommendation about how much weight they should gain, only 12.0% (95% confidence interval, 8–16.1%) of the women reported having achieved the recommended weight gain in accordance with the 2009 guidelines. One quarter of the women reported being told that there were risks with inappropriate gain.
Conclusion
Despite the recent 2009 publication of the gestational weight gain guidelines, only 12% of women reported being counseled correctly, which suggests an urgent need for improved patient education.
Key words
Women of childbearing age are particularly vulnerable for becoming obese,
1
in part because of excess weight gain during pregnancy.2
High gestational weight gain is associated with a 2- to 3-fold increased risk of becoming overweight after delivery3
and, along with failure to lose weight after delivery, is an important predictor of obesity in midlife.4
In 2009, the Institute of Medicine released new gestational weight gain recommendations,
5
which were adopted by several other countries, including Canada,6
that advised that underweight women (body mass index [BMI], <18.5 kg/m2) gain 12.5-18 kg (28-40 lbs), normal weight women (BMI, 18.5-24.9 kg/m2) gain 11.5-16 kg (25-35 lbs), overweight women (BMI, 25-29.9 kg/m2) gain 7-11.5 kg (15-25 lbs), and obese women (BMI, ≥30 kg/m2) gain 5-9 kg (11-20 lbs).Despite the current guidelines and their 1990 predecessor,
7
only 308
-40%9
, 10
of pregnant women gain the appropriate amount of weight during pregnancy. More than one-half of women exceed the recommendations,11
which significantly increases the risks to their health both during pregnancy (gestational diabetes mellitus,12
hypertension,13
delivery complications such as cesarean section and operative vaginal delivery12
), and longer term (overweight3
and obesity4
). Excess gestational weight gain increases risks for infants of macrosomia,12
birth trauma, and childhood overweight.14
Conversely, inadequate gestational weight gain increases infant risks of low birthweight and prematurity.15
- Han Z.
- Lutsiv O.
- Mulla S.
- Rosen A.
- Beyene J.
- McDonald S.D.
Low gestational weight gain and the risk of preterm birth and low birthweight: a systematic review and meta-analyses.
Acta Obstet Gynecol Scand. 2011; (May 31, Epub ahead of print)https://doi.org/10.1111/j.1600-0412.2011.01185.x
Despite the well-documented adverse maternal, infant, and childhood outcomes that accompany both excess and inadequate gestational weight gain, data are lacking on the extent to which women are counseled about the risks of inappropriate weight gain during pregnancy, and there are no data on the proportion of women who have been counseled about gestational weight gain since the new guidelines were released.
5
We sought to address the current paucity of information through a survey of pregnant women to determine what they understand about the counseling from their health care provider about weight gain during pregnancy and the risks of inappropriate weight gain.Materials and Methods
We conducted a cross-sectional survey using a piloted, self-administered questionnaire.
Study population
The study population included pregnant women who were attending prenatal care provided by obstetricians, midwives, nurse practitioners, and family physicians in Hamilton, Ontario, Canada, from representative clinics in obstetrics (4), family medicine (3), and midwifery (2).
Women were eligible to participate if they had had at least 1 prenatal visit, could read English sufficiently well to complete the survey, and had a live singleton gestation.
Women were ineligible for the study if they had experienced a fetal death by the time of survey completion or were pregnant with >1 fetus.
Recruitment
Pregnant patients were invited to participate in the study by clinic staff and prenatal care providers. Posters that informed patients about the study were displayed at clinics. Blank surveys were provided to each participating clinic, along with clipboards, pens, and drop boxes for completed surveys.
This study was approved by the Hamilton Health Sciences/McMaster University Faculty of Health Sciences Research Ethics Board before study commencement (#10-214). As per the introductory paragraph on the first page of the survey, consent to participate was demonstrated through survey completion; no identifying information was collected.
Outcomes
Our primary outcomes were the proportion of women who reported being counseled at all and the proportion of women who were counseled appropriately according to the guidelines about how much weight to gain. We assessed this by asking, “Has your doctor, midwife, or nurse made a recommendation about how much weight you should gain during pregnancy (total amount of weight)?” Respondents could check “No,” “Yes” (in which case they were asked “How much?”), or “I can't remember.” We chose to assess patient recall of the counseling rather than what the health care providers reported, because it is ultimately the patient's own recall that will direct her weight gain. We calculated the respondent's prepregnancy BMI from the self-reported prepregnancy weight and height and determined whether the recommendation was within the guidelines. Secondary outcomes included reported counseling about the risks of inappropriate gain, the women's perceptions of the risks of inappropriate gain, plans for weight gain during pregnancy, and knowledge of weight-related lifestyle issues that included nutrition and exercise. For all questions that involved height or weight, patients were given the choice of responding in imperial or metric units.
Statistical analysis
We performed duplicate data entry using Access Database software (Microsoft Corporation, Redmond, WA), then checked and corrected any inconsistencies, and analyzed the data using PASW Statistics 18 (SPSS Inc, Chicago, IL). Descriptive statistics were performed to characterize the respondents (eg, maternal age, parity). Characteristics of women who were and were not counseled appropriately about gestational weight gain were compared with the use of a t test for continuous data and χ2 test for proportions. With having been appropriately counseled as to the outcome or dependent variable, logistic regression analysis was planned to control for potentially confounding variables, such as maternal age and parity.
Sample size was set to estimate the proportion of women who reported correct counseling to within ±6%. For a given proportion (p) and sample size (n), the 95% CI around the proportion will be a probability of ±1.96 square root (p [1 – p]/n). We were unsure as to the proportion of women who would be counseled correctly but noted that precision is always the worst (ie, CIs the widest) when the probability value is .5. Thus, 266 valid responses would allow us to estimate proportions to the required precision. Allowing for 15% of respondents missing data, a total of 310 women were needed to achieve the desired precision.
Results
Three hundred ten women completed the survey between June and October 2010, which was a 93.6% response rate (of 331 eligible women who were approached by the clinic staff). The characteristics of the study sample are shown in Table 1. The mean age of the respondents was 29.5 ± 5.7 years; they completed the survey at a median gestational age of 33 weeks (interquartile range, 26.4–36.7 weeks' gestation). Most women were white (73.9%), and had some amount of postsecondary education (76.8%). Approximately one-third of women reported a household income of $20,000-$80,000; another one-third reported an income of >$80 000. Most of the women were either married (65.5%) or in a common-law relationship (17.1%). It was the first time giving birth for 42.6% of women; 34.5% of the women had given birth once before. The mean prepregnancy BMI of respondents was 25.1 ± 6.7 kg/m2; the breakdown of underweight, normal weight, overweight, and obese women was 6.5%, 52.3%, 20.6%, and 13.5%, respectively.
TABLE 1Characteristics of the study sample of survey participants
| Variable | Respondents, n |
|---|---|
| Maternal age, y | 29.5 ± 5.7 |
| Gestational age, wk | 33.0 (26.4-36.7) |
| White, n (%) | 229 (73.9) |
| Married or common-law, n (%) | 256 (82.5) |
| Education, n (%) | |
| Any postsecondary | 234 (76.8) |
| Secondary or less | 72 (23.2) |
| Income, n (%) | |
| High, >$80 000 | 105 (33.9) |
| Middle, $20,000-80,000 | 106 (34.2) |
| Low, <$20,000 | 52 (16.8) |
| Unreported | 47 (15.2) |
| Current smoker, n (%) | 32 (10.3) |
| Pregnancy history, n (%) | |
| First time giving birth | 132 (42.6) |
| 1 previous birth | 107 (34.5) |
| ≥2 previous births | 56 (18.1) |
| Unreported | 15 (4.8) |
| Prepregnancy body mass index (kg/m2) of 288 (92.9%) respondents | 25.1 ± 6.7 |
| Body mass index classification, n (%) | |
| Underweight (<18.5 kg/m2) | 20 (6.5) |
| Normal weight (18.5-24.9 kg/m2) | 162 (52.3) |
| Overweight (25.0-29.9 kg/m2) | 64 (20.6) |
| Obese (>30 kg/m2) | 42 (13.5) |
McDonald. Few report counsel about weight gain during pregnancy. Am J Obstet Gynecol 2011.
a Unless otherwise indicated;
b Data are given as mean ± SD;
c Data are given as median (interquartile range).
A minority of women reported being counseled either at all or correctly about how much weight to gain during pregnancy by their health care provider, which were our 2 primary outcomes. Twenty-eight percent of patients (28.5%; 95% confidence interval [CI], 23.5–33.6%) reported that their health care provider had recommended that they gain a certain amount (or range) of weight; however, only 12.0% (95% CI, 8–16.1%) of patients reported that they were counseled to gain an amount within the recommended guideline (Table 2). Most patients reported that weight gain was not discussed at all (51.3%); 44.8% of the patients reported that exercise was not discussed.
TABLE 2Patient perception of prenatal counseling recommendations
| Outcome | Respondents, n (%) |
|---|---|
| Received gestational weight gain counseling from their health care provider | |
| To gain a specific amount or range | 87 (28.5) |
| To gain the correct amount or range | 31 (12.0) |
| Weight gain discussed at all | 142 (47.2) |
| Received counseling from their health care provider that there are risks with excess weight gain | 78 (25.3) |
| Believe there are risks with excess weight gain | |
| For themselves | 50 (63.3) |
| For their infant | 42 (56.0) |
| Received counseling from their health care provider that there are risks with inadequate weight gain | 69 (22.3) |
| Believe there are risks with inadequate weight gain | |
| For themselves | 17 (21.3) |
| For their infant | 28 (37.8) |
| Were counseled to consume an amount or range of additional calories each day by health care provider | 253 (17.9) |
| 100-300 calories | 23 (41.8) |
| 300-500 calories | 6 (10.9) |
| Could not recall how many | 21 (38.0) |
| Were counseled to take a vitamin by health care provider | 301 (96.8) |
| Difference between the amount of weight the patient was intending to gain and the amount recommended by their health care provider, kg | 0.93 ± 3.0 |
| Family and friends made recommendations about how much to gain | 64 (20.8) |
| Difference between the amount of weight the patient was intending to gain and the amount recommended by family and friends, kg | 0.17 ± 2.0 |
| Believe a tool to calculate how much weight gain should be gained in total and each week would be helpful | |
| Probably or definitely helpful | 158 (52.7) |
| Chart or website ranked first | 203 (69.6) |
McDonald. Few report counsel about weight gain during pregnancy. Am J Obstet Gynecol 2011.
a Except as indicated;
b Data are given as mean ± SD.
Approximately one-quarter of the respondents reported being told that there were risks with either excess weight gain (25.5%) or inadequate weight gain (22.3%). However, a higher proportion (63%) correctly believed that there were risks to themselves in gaining more than is recommended; 56% of the women rightly believed there were infant risks. Conversely, 21% of the women incorrectly believed that there were risks to themselves to gaining less than what was recommended; 38% of the women correctly identified that the infant was at risk.
Two-thirds of patients (66.5%) reported that they used information sources on weight gain and nutrition besides their health care provider. Only 8 women (3%) had been referred to a dietician or nutritionist. When patients' families and friends made recommendations about how much weight should be gained (20%), they were generally in accordance with the amount recommended by the health care provider (mean difference, +0.17 ± 2.0 kg); 100% of the recommendations were within 5 kg. In most cases, patients were planning to gain a similar amount of weight as their health care provider recommended (mean difference, +0.93 ± 3.0 kg); 92% were within 5 kg.
Patients reported that weight-related issues were discussed rarely by their health care provider. In contrast, 96.8% of patients reported that their health care provider had recommended that they take a vitamin. In addition, 84% of patients reported that they were either “comfortable” or “very comfortable” discussing weight-related issues with their health care provider.
Fewer than 1 in 5 patients (17.7%) reported that their health care provider recommended that they eat a specific range of additional calories each day; one-third of them could not recall the amount that had been recommended. Approximately one-half of the patients (52.7%) thought that an aid or tool that would calculate how much weight should be gained each week and in total would either “probably” or “definitely” be helpful; 69.6% of the patients ranked as first either a chart from their health care provider that would show appropriate weight gain or a website.
Few of the women (37%) were planning to gain weight within the guidelines; the distribution of the respondents was underweight, normal weight, overweight, and obese (26.3%, 54.4%, 15.0%, and 11.9%, respectively; Table 3). Thirty-nine percent (39.2%) of women overall inadvertently were planning to gain weight above the guidelines (31.6%, 15.6%, 75.0%, and 73.8% of underweight women, normal weight women, overweight women, and obese women, respectively). Twenty-four of the women (23.9%) inadvertently were planning on gaining less than the guidelines (42.1%, 29.9%, 10.0% and 14.3%, respectively, of underweight women, normal weight women, overweight women, and obese women).
TABLE 3Patients' plans for weight gain
| Body mass index category | Patients' plans for weight gain during pregnancy | Total | ||
|---|---|---|---|---|
| Within guidelines | Below guidelines | Above guidelines | ||
| Underweight | 5 (23.6%) | 8 (42.1%) | 6 (31.6%) | 19 (100.0%) |
| Normal weight | 80 (54.4%) | 44 (29.9%) | 23 (15.6%) | 147 (100.0%) |
| Overweight | 9 (15.0) | 6 (10.0%) | 45 (75.0%) | 60 (100.0%) |
| Obese | 5 (11.9%) | 6 (14.3%) | 31 (73.8%) | 42 (100.0%) |
| Total | 99 (36.9%) | 64 (23.9%) | 105 (39.2%) | 268 (100.0%) |
Two hundred sixty-eight of 310 participants (86.4%) provided information about their plan for weight gain during pregnancy, prepregnancy height, and weight.
McDonald. Few report counsel about weight gain during pregnancy. Am J Obstet Gynecol 2011.
With only 31 patients counseled to gain the correct amount of weight, there was inadequate power to determine the variables that were associated with having been counseled correctly either on univariate analysis (Table 4) or multivariate at analysis with maternal age and BMI in the equation (data not shown, not significant).
TABLE 4Predictors of patient report of being counseled correctly or not
| Variable | Counseled appropriately | Not counseled appropriately or at all | P value |
|---|---|---|---|
| Age, y | 31.2 ± 4.46 | 29.4 ± 5.87 | .045 |
| Body mass index, kg/m2 | 23.9 ± 4.60 | 25.29 ± 7.06 | .089 |
| First time giving birth, n (%) | .108 | ||
| Yes | 17 (14.7) | 99 (85.3) | |
| No | 14 (8.5) | 150 (91.5) | |
| Education, n (%) | .267 | ||
| High school or less | 4 (6.6) | 57 (93.4) | |
| Beyond high school | 25 (11.5) | 193 (88.5) | |
| Income, n (%) | .162 | ||
| Low | 5 (6.4) | 73 (93.6) | |
| Middle | 6 (9.4) | 58 (90.6) | |
| High | 15 (15.2) | 84 (84.8) | |
| Race, n (%) | .335 | ||
| White | 25 (11.8) | 187 (88.2) | |
| Not | 5 (7.6) | 61 (92.4) | |
| Type of health care provider, n (%) | .674 | ||
| Family doctor | 8 (10.3) | 70 (89.7) | |
| Midwife | 13 (16.3) | 67 (83.8) | |
| Obstetrician | 8 (9.2) | 79 (90.8) | |
| Other | 2 (5.9) | 32 (94.1) | |
| Smoker, n (%) | .081 | ||
| Yes | 6 (20.7) | 20 (79.3) | |
| No | 25 (10.0) | 226 (90.0) |
McDonald. Few report counsel about weight gain during pregnancy. Am J Obstet Gynecol 2011.
a Data are given as mean ± SD;
b Equal variances not assumed;
c Mann-Whitney U test;
d Pearson χ2 exact test, 2-sided;
e Includes maternity center (a program involving nurse practitioners and family physicians), nurse, nurse practitioner and other categories.
Comment
Despite the publication of the 2009 gestational weight gain guidelines, we found that only 1 in 10 women reported being counseled to gain the correct amount of weight during pregnancy. Although one might have hypothesized that the release of the guidelines would have improved counseling, this was not the case; we report the lowest rates of appropriate counseling in the literature to date. In 1980, 61% of pregnant women in the 1988 National Maternal and Infant Health Survey
16
received advice about weight gain, which is a proportion that increased to 73% in the late 1980s17
and early 1990s18
; only 47% of pregnant women were counseled correctly.18
During the mid-1990s, 38.4% of women received weight gain information, with 31.5% being counseled correctly.9
Given the very high survey response rate (93.6%) and the high proportion (84%) of patients who reported being comfortable or very comfortable discussing weight-related issues with their health care provider, it appears unlikely that the lack of counseling is due to patient-driven factors apart from forgetting. The lack of counseling may be due to the fact that some health professionals consider gestational weight gain “not important,”
19
despite clear evidence to the contrary. Knowledge deficits may be compounded by the practitioners' own weight, because self-identified “overweight” physicians had almost 4 times as much difficulty counseling about weight as average weight physicians (adjusted odds ratio, 3.8; 95% CI, 1.1–13.3).20
Other factors may include lack of time or skills in counseling about gestational weight gain.Compared with receiving counseling by a health care provider, a lack of reported counseling is associated with inappropriate gestational weight gain, both inadequate and excessive.
18
Excess gain is a key contributor of obesity in mid-life,4
and the low proportion of women who were counseled correctly is striking because the survey was conducted in a city in which excess weight is a dominant problem, with 74% of adults being overweight or obese.21
To our knowledge, this is the first study to determine whether women were counseled about the risks of inappropriate weight gain because this information could serve as motivation for women. We found that only approximately one-quarter of the respondents were informed that there were risks with excess gain or inadequate gain.Strengths of our study include the very high response rate, which minimized volunteer participation bias and, along with our broad inclusion criteria, allows us to generalize our findings to women with singleton gestations who can read English and were receiving prenatal care in our region. We asked women about previously unexplored issues related to gestational weight gain that included whether they believed there were risks of inadequate or excess gain for themselves or for their baby and whether these had been discussed by their health care provider. Moreover, by asking whether a vitamin was recommended, we could compare counseling that was related to various aspects of nutrition. The fact that women were surveyed at a median of 33 weeks' gestation means that most of them would have had multiple opportunities for discussions about weight gain over the course of their prenatal care. Although some patients may have forgotten part of what they were counseled during the preceding months, given that a large portion of weight gain occurs during the third trimester, the median gestational age of 33 weeks at the time of the survey seems fortuitous. We deliberately focused on what patients recalled being counseled, rather than what their health care provider reported saying, because the health care providers' impressions of their own counseling abilities could exceed those of the patients' and because it is ultimately only what the patient can recall that will guide her weight gain.
Limitations of our study include the cross-sectional nature, which meant that we could not gather information on actual weight gain; however, this was not the interest of our study because the relationship between a lack of counseling and subsequent inappropriate gain has been established already.
18
In addition, there were so few women who received appropriate counseling that we had inadequate power to analyze associated factors. New guidelines can take time to be incorporated into practice; however, the 2009 guidelines had similar cutoffs for weight gain as their predecessor in 19907
; moreover, only 28.5% of patients reported that their care provider had made a recommendation about how much weight they should gain. Although we used the women's self-reported prepregnancy weight and height to calculate BMI, this has been shown to be highly accurate compared with measured values.22
, 23
, 24
In conclusion, despite the publication of the 2009 guidelines, we found that only 1 in 10 women reported that she was counseled to gain the correct amount of weight during pregnancy, which likely contributed to the fact that three-quarters of overweight and obese women inadvertently were planning to exceed the recommendations. The results of this study point to an urgent need for improved patient education, potentially in part through a tool to guide women about weight gain. Further research is now needed to develop and test interventions to improve counseling about and women's knowledge about appropriate gestational weight gain and to determine whether maternal and infant outcomes can be ameliorated.
Acknowledgments
We thank the women who shared their thoughts with us in this survey and the staff at the clinics who invited them to participate, including Drs Ann Marie Chen, Carmela Sciarra, Caroline Sibley, Robert Hutchison, Denise Campeau, all from the Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada; Dr Keyna Bracken from the Department of Family Medicine, McMaster University, Hamilton, Ontario, Canada; Ms Catherine Good, the Maternity Centre of Hamilton; the Community Midwives of Hamilton; and the Hamilton Midwives. We thank the QuEST group from St Joseph's Healthcare Mental Health, Hamilton, Ontario, Canada, for their input into the survey design, in particular, Dr David Streiner for his methodologic guidance in the survey development.
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Article Info
Publication History
Published online: May 30, 2011
Accepted:
May 18,
2011
Received in revised form:
May 6,
2011
Received:
January 27,
2011
Footnotes
Staff members at participating clinics who were involved in the survey and others who assisted with the research are listed in the Acknowledgments.
Supported in part by a Canadian Institutes of Health Research (CIHR) New Investigator Award (S.D.M.); CIHR had no role in the conduct, analysis, or interpretation of this study.
The authors report no conflict of interest.
Cite this article as: McDonald SD, Pullenayegum E, Taylor VH, et al. Despite 2009 guidelines, few women report being counseled correctly about weight gain during pregnancy. Am J Obstet Gynecol 2011;205:333.e1-6.
Identification
Copyright
© 2011 Mosby, Inc. Published by Elsevier Inc. All rights reserved.
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- October 2011 (vol. 205, no. 4, page 333)American Journal of Obstetrics & GynecologyVol. 212Issue 1
