Conceived and designed the experiments: JMW MBH ABC RHL. Performed the experiments: JMW MBH KH. Analyzed the data: JMW SCS EE RM. Contributed reagents/materials/analysis tools: SCS RM. Wrote the paper: JMW MBH.
The authors have declared that no competing interests exist.
Latino children are at increased risk for mirconutrient deficiencies and problems of overweight and obesity. Exposures in pregnancy and early postpartum may impact future growth trajectories.
To evaluate the relationship between prenatal and postnatal maternal depressive symptoms experienced in pregnancy and infant growth from birth to 2 years of age in a cohort of Latino infants.
We recruited pregnant Latina mothers at two San Francisco hospitals and followed their healthy infants to 24 months of age. At 6, 12 and 24 months of age, infants were weighed and measured. Maternal depressive symptoms were assessed prenatally and at 4-6 weeks postpartum. Women who had high depressive symptoms at both time periods were defined as having chronic depression. Logistic mixed models were applied to compare growth curves and risk for overweight and underweight based on exposure to maternal depression.
We followed 181 infants to 24 months. At 12 and 24 months, respectively, 27.4% and 40.5% were overweight, and 5.6% and 2.2% were underweight. Exposure to chronic maternal depression was associated with underweight (OR = 12.12, 95%CI 1.86-78.78) and with reduced weight gain in the first 2 years of life (Coef = -0.48, 95% CI -0.94—0.01) compared with unexposed infants or infants exposed to episodic depression (depression at one time point). Exposure to chronic depression was also associated with reduced risk for overweight in the first 2 years of life (OR 0.28, 95%CI 0.03-0.92).
Exposure to chronic maternal depression in the pre- and postnatal period was associated with reduced weight gain in the first two years of life and greater risk for failure to thrive, in comparison with unexposed infants or those exposed episodically. The infants of mothers with chronic depression may need additional nutritional monitoring and intervention.
Maternal prenatal depression can have significant and critical negative impact in fetal development and occurs in approximately 7 to 13% of childbearing women
In addition to the above described associations between prenatal and postnatal depression, lower birthweight, and failure to thrive, maternal postnatal depressive symptoms have also been associated with risk for pediatric overweight in the first 2 years of life. In a cross-sectional study from Brazil, Surkan et al, reported that postnatal depressive symptoms (from 6-24 months) are associated with increased risk for overweight and obesity for children between 6 and 24 months of age
Studies suggest that the time period of exposure is likely important in determining childhood outcome. A recent US-based study found that children exposed to antenatal maternal depression have a lower BMI z-score at 3 years of age, while those exposed to postnatal maternal depression at 6 months have higher overall adiposity
No study to date has evaluated the combined impact of exposure to prenatal and postnatal depression in a population at high risk for future obesity such as Latino infants, in comparison with unexposed infants or those exposed to maternal depressive symptoms either prenatally or postnatally. Such an approach is needed as the infants of women who have more intractable depressive symptoms that span the perinatal period may have different growth trajectories in comparison with infants who do not have these environmental exposures or a more limited form of exposure (either prenatal or postnatal).
The early growth trajectories of Latino children are an important group to assess given the high prevalence of nutritional deficiencies in this population as well as the high risk of future obesity. Latino children have high prevalences of zinc deficiency
Latina women were recruited during the 2nd and 3rd trimesters of pregnancy at prenatal clinics at the University of California, San Francisco (UCSF) Medical Center and San Francisco General Hospital (SFGH) from May 2006 to May 2007, and were followed through labor and delivery until the infants reached 2 year of age. Exclusion criteria included drugs or alcohol abuse, pre-existing diabetes mellitus or gestational diabetes mellitus treated with insulin, polycystic ovarian syndrome, any eating disorders such as bulimia or anorexia nervosa, or any health problems that would influence breast-feeding. Infants at delivery were excluded if they had special care needs, chronic disease, or Apgar scores of less than 7 at 5 minutes. Close to 100% of Latina women were approached in both hospitals as we had a continuous on-site research presence. Approximately 90% of those who met the inclusion criteria for the study agreed to participate.
All procedures were approved by the Committee on Human Research at UCSF and the Institutional Review Board at SFGH. Following informed consent, baseline data and socio-demographics of the participants including age, education, occupation, income, marital status, language use and length of time in the United States were collected. Medical history was also ascertained through chart review and by questionnaire to determine mental health history, including previous diagnosis and/or treatment for depression or anxiety. Maternal pre-pregnancy weight was collected at baseline by self-report. Questions on legal status or migration history were not asked other than length of time in the United States because of the sensitive nature of these questions and the possibility that questioning in this area could compromise the validity of our study or jeopardize the follow-up rate. Additional specifics about our study population are described in Wojcicki et al.
Upon enrollment, mothers were administered the Edinburgh Postpartum Depression Scale (EPDS)
At birth, anthropometric measurements of the infant, including infant weight (using standard digital infant scales) and length (using standard tape measurements) were obtained. Gestational age and Apgar scores were recorded. At 4–6 weeks postpartum, participants were contacted by phone and interviewed again for depressive symptoms and clinical depression using the same instruments employed at baseline. Additionally, infant feeding was assessed using a 24 hour dietary recall. At 6, 12 and 24 months post-partum, the infants were weighed and measured. Maternal weight (using a Seca digital scale recording weight to nearest 0.1kg) and height (using a portable stadiometer to nearest 0.1cm) were measured between 12 and 24 months postpartum to calculate body mass index (BMI) (kg/m2). Waist circumference in children was measured at 24 months of age in a sub-sample of the cohort (n = 156). A small percentage of the cohort (between 3–5% depending on timepoint) were not available to be measured so weight and height were extracted from the medical record. BMI <25 kg/m2 was categorized as normal/underweight, 25≤ BMI <30 was categorized as overweight, and BMI ≥30 was categorized as obese, using standard definitions from the World Health Organization
The main predictor of interest was depressive symptoms experienced either prenatally and/or at 4–6 weeks postpartum described more in detail below. The main outcome was child weight-for-length z-score at 6,12, and 24 months of age. Actual ages at post-partum visits varied somewhat from these values, so analyses used ages from observed visits. Analyses based on the grouped ages (0, 6, 12 and 24 months) yielded very similar results (not shown). Secondary outcomes of interest included risk for underweight/failure to thrive (<5th percentile weight-for-age), overweight (≥85th percentile weight-for-length or body mass index) and obese (≥95th percentile weight/height or body mass index) as described in more detail below. Additional predictor variables considered for multivariate regression models included infant birth weight z-score or birth weight-for-length z-score, any breast-feeding at 6 months of age, maternal postnatal (12–24 months) BMI, maternal ethnicity (Central American versus Mexican), maternal age and gestational age. Additional details about specific analyses are described below. Birthweight andg birthweight for length Z scores were adjusted for in the analyses because our primary outcome of interest was weight gain from 6 months to 2 years of age in relation to prenatal and postnatal maternal depression exposures.
Exposure to pre- or postnatal depressive symptoms were defined by: 1) CESD ≥16; 2) EPDS ≥13; or 3) having a major depressive episode or dysthymia as per the MINI. A high depression symptom score was defined as a high score on one of the above measures prenatally or at the 4–6 week timepoint. Chronic depression was defined as having a high score at both time points (including a possible diagnosis of clinical depression as per the MINI at either time point) and episodic depression was defined as having depression at one time point (including a possible diagnosis of clinical depression as per the MINI at either time point). We also evaluated the relationship between weight trajectories and not ever having depressive symptoms compared with having depressive symptoms only in the prenatal period, only in the postnatal period, and at both time-points.
Overweight (≥85th percentile BMI or weight/length) and obesity (≥95th percentile BMI or weight/length) up until 24 months were defined by the National Center for Health Statistics, Center for Disease Control and Prevention weight-for-length and body mass index growth curves
Chi-squared tests of association, analysis of variance (ANOVA) and Student's t-tests were applied to evaluate the relationships between exposure to prenatal and/or postnatal depression and weight/length percentiles, risk for underweight and risk for overweight and obesity. Mixed effects linear regression models were used to evaluate differences in weight-for-length z-scores over the two-year period in relation exposure to maternal depression adjusting for the potential confounders described above. Models included random intercepts, and random slopes for time effects. Differences in individual weight trajectories between groups reporting different levels of depression were evaluated via inclusion of appropriate interaction terms in fitted models. Mixed effects logistic regression models were used to determine risk factors for failure to thrive, overweight and obesity. Time effects were modeled using the same approach described for linear models. Outcomes for logistic and linear models only included data from visits occurring post-birth as our major predictors included postnatal depression at 4-6 weeks postpartum. As birthweight occurred prior to postnatal depression, it was not possible to include birthweight in the longitudinal analysis as an outcome because of the temporal sequence of events.
Only women who had all data on the selected variables were included in the multivariate models. Data were entered into Excel, and subsequent analyses were conducted using Stata 11.0 (Stata Corporation, College Station, TX, USA).
In order to assess the possible role of missing data on our estimates, multiple imputation methods were used in Stata 9.0 using the command
We enrolled 201 women in the cohort18 and followed 175 women to 6 months of age and 174 to 12 months of age and 181 to 2 years of age. The majority of our cohort (61.2% [123/201]) was Mexican ethnicity; the remainder was primarily of Central American origin (El Salvadorian, Guatemalan and Honduran). Most women (92.0%) were participants in the Women, Infants and Children's Program (WIC), 31.0% were married, and 52.0% were living with partner. Our participants tended to have a high school diploma or less (76.0%), and 92.9% cited Spanish as their primarily language. The mean number of other children in the household was 0.83±0.99. The majority of the infants in the cohort were born vaginally (85.6%). Mean gestational age was 39.3 weeks, and mean birthweight was 3.37±0.48 kilograms as described in Wojcicki et al.
Prenatally, 28.9% of participants had depressive symptoms or clinical depression. At 4–6 weeks post-partum this number declined to 15.7%. Depressive symptoms were evident in 22.5% of women at the prenatal or 4–6 week time point, and 11.0% had chronic depression at the prenatal and 4–6 week timepoint. A smaller 4.0% (8/201) had clinical depression prenatally and 4.3% at 4–6 weeks but only one of these eight had clinical depression at both time-points.
At birth, 7.4% of infants were overweight. By 6 months of age this increased to 26.1%, at 12 months to 27.6%, and at 2 years to 40.5%. At birth, 2.1% of infants were obese; this percentage increased to 11.1% at 6 months, 12.6% at 12 months, and 20.2% at 2 years of age. At birth, an expected 5.2% were <5th percentile for weight. By 2 years of age, only 2.2% were <5th percentile for weight (
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Birth | 7.4 (14/189) |
6 months | 26.1 (47/180) |
12 months | 27.4 (48/174) |
2 years | 40.5 (72/178) |
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Birth | 2.1 (4/189) |
6 months | 11.1 (20/180) |
12 months | 12.6 (22/175) |
2 years | 20.2 (36/178) |
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Birth | −.51±1.10 |
6 months | .40±1.10 |
12 months | .31±1.24 |
2 years | .83±1.31 |
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Birth | 5.2 (10/194) |
6 months | 1.7 (3/181) |
12 months | 5.5 (10/182) |
2 years | 2.2 (4/181) |
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2 years | 8.3 (13/156) |
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12 months-2 years | 28.3±6.3 |
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32.5 (62/191) |
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34.0 (65/191) |
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33.5 (64/191) |
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Any Breast-feeding (BF) @ 4-6 wks postpartum (%, (N/Total)) | 91.2 (175/192) |
Exclusive BF @ 4–6 weeks (%, (N/Total)) | 37.4 (71/190) |
Any BF @ 6 months (%, (N/Total) | 70.0 (126/180) |
Any BF @ 12 months (%, (N/Total) | 39.4 (67/170) |
Age of Solids Introduction (months) (Mean |
5.2±1.5 |
A high percentage (91.2%) of the mothers were breast-feeding (BF) at 4–6 weeks, 70.0% at 6 months, and 38.8% at 12 months of age (
Exposure to chronic maternal depression was associated with decreased frequency of overweight at 6, 12 and 24 months, although the results did not achieve statistical significance (
Values at each timepoint are unadjusted mean values.
Values at each timepoint are unadjusted mean values.
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Birth | 4.8 (1/21) | 9.5 (4/42) | 6.6 (8/121) | 0.74 |
6 months | 19.1 (4/21) | 22.0 (9/41) | 29.3 (34/116) | 0.47 |
12 months | 10.0 (2/20) | 23.7 (9/38) | 32.2 (37/114) | 0.096 |
2 years | 25.0 (5/20) | 40.0 (16/40) | 43.5 (50/115) | 0.30 |
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Birth | 0.0 (0/21) | 7.1 (3/42) | 0.8 (1/121) | 0.04 |
6 months | 4.8 (1/21) | 9.8 (4/41) | 13.0 (15/116) | 0.52 |
12 months | 0.0 (0/20) | 10.5 (4/38) | 15.7 (18/115) | 0.14 |
2 years | 15.0 (3/20) | 22.5 (9/40) | 20.9 (24/115) | 0.79 |
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Birth | −0.62±0.93 | −0.48±1.37 | −0.51±1.01 | 0.88 |
6 months | 0.016±1.10 | 0.22±1.09 | 0.53±1.05 | 0.07 |
12 months | −0.089±0.99 | 0.40±1.09 | 0.34±1.33 | 0.31 |
2 years | 0.58±1.31 | 0.96±1.50 | 0.83±1.24 | 0.57 |
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Birth | 4.8 (1/21) | 9.5 (4/42) | 4.0 (5/126) | 0.38 |
6 months | 9.5 (2/21) | 0.0 (0/41) | 0.9 (1/117) | 0.01 |
12 months | 20.0 (4/20) | 5.0 (2/40) | 3.3 (4/120) | 0.01 |
2 years | 5.00 (1/20) | 2.5 (1/40) | 1.7 (2/118) | 0.65 |
Logistic mixed modeling revealed that exposure to chronic depression within the first two years of life was associated with a decreased weight-for-length z-score (Coef −0.43, 95%CI −0.89—0.02) compared with no exposure or exposure only episodically (
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No Depressive Symptoms | 0.00 | |
Episodic Depression | −0.05 (−0.40−0.29) | 0.76 |
Chronic Depression | −0.42 (−0.88−0.03) | 0.07 |
Study Visit Time (6mo, 12 mo or 2 years) | 0.03 (0.02−0.04) | <0.01 |
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No depressive symptoms | 0.00 | |
Episodic depression | −0.09 (−0.45−0.27) | 0.64 |
Chronic depression | −0.48 (−0.94—0.01) | 0.045 |
Any breastfeeding @ 6mo | −0.25 (−0.60−09) | 0.15 |
Mexican ethnicity | −0.09 (−0.41−0.22) | 0.55 |
Maternal postnatal BMI | 0.02 (−0.0008−0.05) | 0.06 |
Maternal age | −0.03 (−0.06—0.002) | 0.04 |
Gestational age | 0.11 (0.005−0.21) | 0.04 |
Birth Weight-for-Length Z score | 0.10 (−0.03−0.24) | 0.14 |
Study Visit Time, months | 0.03 (0.02−0.04) | <0.01 |
Similarly, exposure to chronic maternal depression was associated with increased risk for failure to thrive/underweight (OR 11.81, 95%CI 1.70–82.61) (
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No Depressive Symptoms | 1.00 | |
Episodic Depression | 1.17 (0.17−8.25) | 0.87 |
Chronic Depression | 11.81 (1.70−82.16) | 0.01 |
Study Visit Time, months | 1.01 (0.93−1.08) | 0.91 |
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No depressive symptoms | 1.00 | 1.00 |
Episodic depression | 0.31 (0.02−4.17) | 0.38 |
Chronic depression | 12.12 (1.86−78.78) | <0.01 |
Maternal postnatal BMI | 1.02 (0.90−1.16) | 0.37 |
Mexican ethnicity | 0.84 (0.17−4.08) | 0.83 |
Any breastfeeding @ 6mo | 8.77 (0.82−93.74) | 0.07 |
Maternal age | 0.99 (0.84−1.15) | 0.87 |
Gestational age | 0.81 (0.43−1.56) | 0.54 |
Birth weight Z score | 0.52 (0.15−1.73) | 0.83 |
Study visit time, months | 1.00 (0.92−1.08) | 0.96 |
*Models are adjusted for all variables listed in the table.
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No Depressive Symptoms | 1.00 | |
Episodic Depression | 0.68 (0.29−1.60) | 0.38 |
Chronic Depression | 0.29 (0.09−0.98) | 0.046 |
Study Time Visit (6mo, 12 mo or 2 years) | 1.06 (1.02−1.09) | <0.01 |
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No depressive symptoms | 1.00 | |
Episodic depression | 0.61 (0.26−1.44) | 0.26 |
Chronic depression | 0.28 (0.03−0.92) | 0.04 |
Maternal postnatal BMI | 1.07 (1.01−1.13) | 0.02 |
Mexican ethnicity | 0.75 (0.36−1.57) | 0.43 |
Any Breastfeeding @ 6mo | 0.81 (0.36−1.82) | 0.60 |
Maternal age | 0.95 (0.89−1.01) | 0.12 |
Gestational age | 1.33 (1.04−1.70) | 0.03 |
Birth weight Z score | 1.33 (0.96−1.84) | 0.08 |
Study Time Visit, months | 1.05(1.02−1.09) | <0.01 |
*Models are adjusted for all variables listed in the table.
When exposure to pre- and post-natal depression was evaluated separately in relation to weight-for-length z-scores and risk for failure to thrive, we did not find differences between the models that evaluated exposures to prenatal and postnatal depression separately and those that evaluated episodic versus chronic exposure to maternal depression. In both models, increased risks for lower weight-for-length z-scores and failure to thrive were associated with exposure to chronic depression compared with infants who were unexposed, exposed to episodic depression, or exposed to prenatal or postnatal depression alone. We also did not find any effect using an interaction term modeling time in relation to maternal depression status so we removed the interaction term from the multivariate models.
Ours is the first study to longitudinally evaluate the relationship between weight gain patterns in the first two years of life in Latino children and exposures to maternal depression in the perinatal period. In contrast to other studies that have evaluated these relationships
Other studies have evaluated relationships between depression and growth either cross-sectionally
Our results also revealed that infants exposed to prenatal depression in utero or to chronic depression were more likely to have failure to thrive in the first 2 years of life compared with children who were unexposed. Previous studies have found that high prenatal cortisol is associated with prematurity and lower birthweight through hyperactivation of the HPA axis
While we did not find any differences in exposure to depression and breastfeeding duration, previous investigators have reported that women with depressive symptoms in the postpartum period have decreased breastfeeding duration and increased breast-feeding difficulties
We did not investigate the relationship between medication use for treatment of depression on infant outcomes because of the low percentage of medication use in our population, although this could be a fruitful area for future research. Similarly, we also did not examine or the role of stress hormones such as cortisol or growth hormones on patterns of weight gain.
From a clinical standpoint, infants of women with chronic depression should be evaluated for failure to thrive and the mothers should potentially be provided with additional nutritional support in addition to any needed psychological or psychiatric intervention. Interventions should be proactive given the behavioral and developmental risk factors associated with failure to thrive. Our results indicate that it is the combined exposures in utero and maternal-child interactions in the postpartum period will also contribute to failure to thrive, in contrast to other studies which have only assessed the role of prenatal depression or postnatal on child weight gain