Nutritional and Weight-Management Behaviors in Low-Income Women Trying to Conceive

Abstract

Objective

To evaluate the nutritional habits and weight management strategies of women trying to conceive as compared to women not trying to conceive.

Methods

This was a cross-sectional survey of health behaviors including nutritional habits and weight management strategies of women aged 16–40 years who were low-income, racially diverse, (n=1,711) and attending reproductive health clinics. Multivariable logistic regression analyses were performed to examine the association between pregnancy intention and various health behaviors after adjusting for demographic variables, gravidity, and obesity status.

Results

At total of 8.9% (n=153) of the participants stated they were trying to get pregnant. Women trying to conceive were more likely than those not trying to have participated in a number of unhealthy weight loss practices in the past year. These included taking diet pills, supplements or herbs (13.5% vs. 8.8%; adjusted odds ratio (aOR) 1.97, 95% confidence interval (CI) 1.11–3.49;), using laxatives or diuretics or inducing vomiting (7.7% vs. 3.0%; aOR 2.70, CI 1.23–5.91;), and fasting for 24 hours (10.7% vs. 5.5%; aOR 2.15, CI 1.03–4.51;). There were no significant differences between the two groups in amount of exercise, current smoking status or current alcohol consumption Further, fruit, green salad and other vegetables, and intake of soda and fast food were unrelated to pregnancy intention.

Conclusion

This study highlights that women trying to conceive are more likely to participate in unhealthy and potentially dangerous weight loss practices than women not trying to conceive.

Introduction

A healthy diet during pregnancy is critical for the future health of the mother and optimal development of the fetus (1, 2). Although most research has focused on the importance of proper nutrition during the prenatal period, nutrition and lifestyle behaviors prior to conception are equally important (3). For example, women are encouraged to discontinue smoking and drinking alcohol both before conception and during pregnancy to reduce the risk of fetal alcohol syndrome and low birth weight infants. In spite of this, many women do not engage in healthy behaviors prior to or during pregnancy (4), independent of pregnancy intention (5–7).

In the past decade, the prevalence of pre-pregnancy obesity has increased to 20.0% in the general population (2009 data) and 28.5% among low-income women (2008 data) (8, 9). Despite this trend, a recent survey found that fewer than 50% of physicians routinely discuss nutritional and weight management practices with their female patients of reproductive age (10). This is concerning as pre-pregnancy obesity is associated with adverse pregnancy outcomes, and the preconception period is a critical time to counsel patients on healthy weight management strategies (1, 11–14). While the importance of achieving a healthy weight in the preconception period is well established (11–15), little is known regarding weight management behaviors in women trying to conceive. This study examined the lifestyle and dietary habits, and weight loss practices among low-income women trying to conceive compared to women not trying to conceive.

Materials and Methods

With University of Texas Medical Branch Institutional Review Board approval, a cross-sectional survey (available in English and Spanish) on health behaviors was administered between July 2010 and April 2011 to women 16–40 years of age attending reproductive health clinics at the University of Texas Medical Branch. These clinics serve low-income women, of whom >80% have annual incomes <$30,000/year. Women were seen for family planning services, pregnancy testing, treatment of sexually transmitted infections, and cervical cancer screening. A total of 2,059 eligible women were approached for participation. Of these, 1,726 agreed to participate for an overall response rate of 83.8%. Fifteen did not respond to the pregnancy intention question so this analysis included 1,711 women.

After obtaining informed consent, participants completed a self-administered questionnaire that included questions pertaining to sociodemographic characteristics. Race and ethnicity were categorized as non-Hispanic white, non-Hispanic black, and Hispanic. Height and weight were obtained from data recorded in the medical chart.

Pregnancy intention was based on the yes or no question, “Are you trying or hoping to get pregnant right now?” Information on frequency of exercise, intake of fruits, vegetables, and green salad, and consumption of fast food and soda (not including diet soda) in the past week was obtained using standard questions. Participants were asked whether, in an effort to lose weight, they engaged in the following unhealthy weight control methods in the past year: “Using diet pills, herbs, supplements without a prescription,” “Using laxatives/diuretics or vomiting after eating,” “Starting to smoke or smoking more cigarettes,” or “Fasted for 24 hours or more.” Answers were provided in a “Yes” or “No” format.

After surveys were collected, they were reviewed individually by a research assistant for missing items and inconsistencies and then reconciled and sent to another staff member for data entry. Descriptive statistical procedures were used to evaluate the data for accuracy and consistency. Additionally, to ensure a precise representation of the physical data, 10% of all weekly surveys were contrasted with their corresponding electronic data.

Bivariate comparisons were performed using the chi-square test or Student’s t test, as appropriate. Multivariable logistic regression analyses were used to examine differences in high-risk behaviors between women with pregnancy intention versus women without pregnancy intention, after adjustment for confounding variables. All analyses were performed using STATA 12 (Stata Corporation, College Station, TX).

Results

Data were available on 1,711 participants (mean age: 26.2; ±SD: 6.2), of whom 17.9% (307) were 16–19 years old. Of these, 8.9% (153) were currently trying to get pregnant. Women with current pregnancy intention were more likely to be non-Hispanic black than non-Hispanic white or Hispanic, and less likely to have a prior pregnancy as compared to those without pregnancy intention (Table 1). While there was no difference in BMI between the groups, 65.1% of women trying to conceive were either overweight or obese while 2.1% were underweight.

Table 1.

Characteristics of reproductive-age women (16–40 years) who intended to get pregnant and not to get pregnant

Characteristics	Total (1711)	Trying to conceive
		Yes (153)	No (1558)	P value
Age, yr, mean(±SD)	1711	25.6 (5.7)	26.3 (6.2)	.251
Race/ethnicity, n (%)	1689			.007*
Non-Hispanic White		31 (20.5)	395 (25.7)
Non-Hispanic Black		80 (52.9)	613 (39.9)
Hispanic		40 (26.5)	530 (34.5)
Education, n (%)	1679			.336
HS drop-out		35 (23.3)	341 (22.3)
Enrolled in HS/HS graduate		74 (49.3)	681 (44.5)
Some college hour/degree		41 (27.3)	507 (33.2)
Household income/year, n (%)	1515			.156
< $15,000		91 (66.4)	876 (63.6)
$15,000–$29,999		25 (18.3)	341 (24.8)
$30,000 or above		21 (15.3)	161 (11.7)
Marital status, n (%)	1673			.703
Never married		70 (47.0)	753 (49.4)
Living together/currently married		60 (40.3)	561 (36.8)
Divorced/separated/widowed		19 (12.7)	210 (13.8)
BMI (kg/m2), n (%)	1634			.311
Under weight(<18.5)		3 (2.1)	49 (3.3)
Normal weight (18.5–24.9)		48 (32.9)	489 (32.7)
Overweight (25.0–29.9)		35 (24.0)	436 (29.3)
Obese (≥30.0)		60 (41.1)	514 (34.5)
Gravidity, n (%)	1708			.003*
None		51 (33.5)	355 (22.8)
≥1 time		101 (66.4)	1201 (77.2)

Numbers represent n (%) or mean (standard deviation)

SD, standard deviation; HS, High School; BMI, body mass index

^*P value <.05 considered statistically significant.

Among women desiring pregnancy, 76.0% consumed <1 serving/day of fruit, 90.0% consumed <1 serving/day of green salad, and 72.9% ate <1 serving/day of vegetables other than salad during the past week (Table 2). Further, 87.6% and 83.2% of pregnancy intenders reported eating fast food and drinking soda during the past week, respectively. While there was no statistically significant difference between the groups in frequency of weekly exercise, 78.7% of women desiring pregnancy did not meet the recommended amount of 30 minutes a day, 5 times a week (16). Moreover, more women trying to conceive than those not trying reported use of diet pills, herbs or supplements (13.5% vs 8.8%), laxatives, diuretics or vomiting (7.7% vs 3.0%), or fasting for ≥24 hours (10.7% vs 5.5%) to lose weight.

Table 2.

Health behaviors among reproductive-age women (16–40 years) trying to conceive versus women not trying to conceive

Behaviors	Total N =1711	Trying to conceive
		Yes N=153	No N=1558	P value
Current smoking status, n (%)	1689			.021*
Yes		54 (35.8)	414 (26.9)
No		97 (64.3)	1124 (73.1)
Current drinking status, n (%)	1689			.883
Yes		78 (53.1)	778 (52.4)
No		69 (46.9)	706 (47.6)
Number of alcohol drinks, n (%)a	807
≤ 2/day		46 (59.0)	457 (62.7)	.520
> 2/day		32 (41.0)	272 (37.3)
Fruit and vegetable consumption, past week, n (%)
Fruits	1372			.697
None/< 1 serving/day		92 (76.0)	931 (74.4)
≥1 serving/day		29 (24.0)	320 (25.6)
Green salads	1363			.066
None/< 1 serving/day		108 (90.0)	1039 (83.6)
≥1 serving/day		12 (10.0)	204 (16.4)
Other vegetables	1331
None/<1serving/day		86 (72.9)	896 (73.9)	.816
≥1 serving/day		32 (27.1)	317 (26.1)
Fast food consumption, past week, n (%)	1368			.031*
Yes		106 (87.6)	990 (79.4)
No		15 (12.4)	257 (20.6)
Soda consumption, past week, n (%)	1359			.758
Yes		99 (83.2)	1045 (84.3)
No		20 (16.8)	195 (15.7)
Exercise (≥30 minutes straight), past week, n (%)	1679			.988
None/< 3days/week		118 (78.7)	1202 (78.6)
≥3 days/week		32 (21.3)	327 (21.4)
Overall quality of sleep, past month, n (%)	1458			.150
Good		95 (71.4)	1020 (77.0)
Bad		38 (28.6)	305 (23.0)
Unhealthy weight loss methods, past year, n (%)
Took diet pills, medicines, herbs, supplements without a prescription	1548			.068
Yes		19 (13.5)	124 (8.8)
No		122 (86.5)	1283 (91.2)
Took laxatives/diuretics or vomited after eating	1547			.003*
Yes		11 (7.7)	42 (3.0)
No		132 (92.3)	1362 (97.0)
Started/restarted smoking or smoked more cigarettes	1537			.005*
Yes		20 (14.0)	102 (7.3)
No		123 (86.0)	1292 (92.7)
Fasted for 24 hours or more	1358			.022*
Yes		13 (10.7)	68 (5.5)
No		109 (89.3)	1168 (94.5)

Numbers represent n (%) or mean (standard deviation)

SD, standard deviation;

^*P value <.05 considered statistically significant

^aAmong those who responded “yes” to current drinking

On bivariate analysis, current use of tobacco, fast food consumption in the past week, and unhealthy weight loss strategies, such as use of laxatives/diuretics/vomiting and fasting for 24 hours, were more common among women trying to conceive compared to those not trying to conceive (Table 2). Both alcohol use and the frequency of drinking >2 alcoholic beverages per day, current drinking status, fruit and vegetable consumption, exercise, past week soda consumption, quality of sleep and intake of diet pills/medicines/herbs/supplements without a prescription were not significantly different between the two groups.

In multivariable logistic regression analysis, women with pregnancy intention were more likely to engage in unhealthy weight management practices such as taking diet pills, herbs, and supplements, taking laxatives/diuretics and engaging in vomiting, and fasting for more than 24 hours (Table 3). Some behaviors differed by race/ethnicity and BMI categories. Compared to whites, black and Hispanic women were less likely to be current smokers or drinkers while Hispanics were more likely to report higher intake of fruits and vegetables, more exercise, and higher quality of sleep with less sleep medication use. They also were less likely to report smoking as a weight loss behavior. Obese women were more likely to report greater consumption of fruits and green salad and more exercise while both overweight and obese women were more likely to practice unhealthy weight loss behaviors. The interaction between pregnancy intention and race/ethnicity, and pregnancy intention and BMI categories were not predictive of any of the unhealthy behaviors mentioned above.

Table 3.

Adjusted odds ratios (95% CI) of health behaviors among reproductive-age women (16–40 years) who intended to get pregnant versus not to get pregnant

Behaviors (outcome variables)a	Adjusted odds ratios (95% CI)
Current smoking status	1.49 (0.98–2.26)
Current alcohol consumption	1.04 (0.72–1.55)
Fruit and vegetable consumption, past week
Fruits	1.08 (0.66–1.73)
Green salads	0.63 (0.33–1.22)
Other vegetables	1.24 (0.78–1.97)
Fast food consumption, past week	1.70 (0.90–3.20)
Soda consumption, past week	1.03 (0.57–1.83)
Exercise, past week	1.05 (0.66–1.67)
Overall quality of sleep, past month	0.88 (0.56–1.37)
Use of sleep medication, past month	1.27 (0.81–2.96)
Unhealthy weight loss methods, past year
Took diet pills medicines, herbs, supplements without a prescription	1.97 (1.11–3.49)
Took laxatives/diuretics or vomited after eating	2.70 (1.23–5.91)
Started/restarted smoking or smoked more cigarettes	1.45 (0.78–2.76)
Fasted for 24 hours or more	2.15 (1.03–4.51)

CI, confidence interval

Separate logistic regression model was used for each of the health behaviors

Main predictor variable: pregnancy intention (yes/no)

^aOutcome variables: each of the health behaviors (binary)

Adjusted by age (continuous), race/ethnicity (non-Hispanic white, non-Hispanic black, and Hispanic), education (HS dropout, enrolled in HS or HS degree, some college hours/college degree), annual income (<$15,000, $15,000–$29,999, $30,000 or above), marital status (never married, living together/currently married, divorced/separated/widowed), body mass index (normal weight, overweight, obese), gravidity (none and ≥1 time)

Discussion

Since obesity is associated with reduced fertility, physicians often recommend weight loss to obese women trying to conceive (17). This study found that women with current pregnancy intention were more likely to engage in unhealthy, potentially dangerous weight loss practices. This could have resulted from misinterpretation of a physician recommendation or a desperation to conceive (18). However, we did not have information regarding whether these women had experienced difficulty conceiving or whether a medical professional advised them to lose weight. Thus, we do not know whether women desiring pregnancy regularly engaged in unhealthy behaviors or if these behaviors were due to a desire to increase their chances of conceiving.

Nearly two-thirds of the women in our study desiring pregnancy were overweight or obese. This supports previous studies, which have shown that many low-income women are overweight or obese before conception (8). This increases their risk of prenatal and postnatal weight gain (19) as well as having preeclampsia, caesarean delivery, or a large-for-gestational-age infant (20, 21). Lifestyle interventions targeting women before conception can improve maternal health behaviors and reduce BMI (22–25). Thus, further efforts are needed to promote healthier dietary habits in overweight and obese women before conception. One possibility is to provide information on healthy programs in reproductive clinics, such as the Mediterranean Diet or Dietary Approaches to Stop Hypertension (DASH) which encourage a high intake of fruit and vegetables, nuts, and legumes, and reduced intake of red and processed meats, as they have been shown to lead to weight loss and improved pregnancy outcomes (1, 26–28). Nutrition education for ethnically-diverse, low-income women also should include culturally appropriate and budget-friendly foods (28). Moreover, preconception care should include screening for unhealthy weight reduction behaviors.

We also found that women trying to conceive were living an “obesigenic” lifestyle, including low fruit and vegetable intake, frequent fast food consumption, and infrequent physical activity. They also engaged in dietary practices that reduce nutrient intake or absorption, such as fasting, using laxatives, and purging. Exposure to an obesigenic environment in utero can alter metabolic development, resulting in future risk of cardiometabolic disease among children (29–31). Further, evidence suggests that dietary intake before conception has similar effects on fetal development as maternal diet during pregnancy (3).

This study has several limitations. First, self-reported data are subject to recall and social-desirability biases. Second, this study was limited to 16–40 year old ethnically-diverse low-income women and thus, findings may not be broadly generalizable. Also, survey questions did not include whether women were experiencing difficulty conceiving so it is unknown if pregnancy intention was related to weight loss behaviors. Some questions had simplified binary responses, which may not have captured the most appropriate responses and some behavior variables had substantial missing data. Finally, we did not have enough power to dismiss the association between pregnancy intention and other non-significant behaviors. Future research with larger populations would shed more light on these relationships.

Considering obstetrician–gynecologists are the primary care providers for many women, they have a unique responsibility to address diet and lifestyle habits with women desiring pregnancy. A healthy preconception diet and weight loss through healthy weight management behaviors can improve pregnancy outcomes, and as such, dietary information should be included in the “well” of well-woman examinations.