Is Mediterranean Diet during pregnancy protective for fetal growth restriction? Results from two prospective cohort studies in Spain and Greece
Leda Chatzi, Michelle Mendez, Raquel Garcia, Theano Roumeliotaki, Jesús Ibarluzea, Adonina Tardón, Pilar Amiano, Aitana Lertxundi, Carmen Iñiguez, Jesus Vioque, Manolis Kogevinas, Jordi Sunyer
On behalf of the INMA and the RHEA birth cohorts study groupsBritish Journal of Nutrition, 2011
Diet in pregnancy
“It is certain thatthe significance of correct nutrition in child-bearing does not begin in pregnancy itself or even in the adult female before pregnancy. It looms large as soon as a female child is born and indeed in its intrauterine life.”.
Edward Mellanby, 1933
Mediterranean Diet
Trichopoulou, 2003
Research Hypotheses/Aims of the study:
To determine prospectively the association
between adherence to the Mediterranean Diet in
pregnancy and fetal growth in the two large
population based mother-child cohorts in the
Mediterranean area (INMA and RHEA mother-child
cohorts)
• Diet assessment
The “Rhea” FFQ: FFQ on 250 items, 17 food groups, completed by personal interview in mid pregnancy (14th-18th week of gestation)
Frequency of consumption: per day, week, and/or per month. Photographs were used to visualize small, medium and large portion sizes for each food item
Mixed dishes: standard recipes were used when available, otherwise new recipes that matched the description of the food were made and the intake of foods from different items was aggregated.
Nutrient analysis: Based on the UK Nutrient Databank (McCance and Widdowson's, 6th edition 2002).
The Greek Mother & Child Cohort Study The Greek Mother & Child Cohort Study
INMA STUDY
INMA AtlanticINMA Mediterranean
The Greek Mother & Child Cohort Study INMA STUDY
• Diet assessment
The “INMA” FFQ: FFQ on 100 items, to assess usual food and nutrient intakes during the first trimester of pregnancy
Frequency of consumption: 9 possible intake frequency categories, ranging from “never or less than once per month” to “6 or more times per day.” Standard units or reference
serving sizes were specified for each food item. Nutrient analysis: Primarily obtained from the US
Department of Agriculture food-composition tables and other published sources.
Maternal adherence to the Mediterranean Diet during pregnancy
• Med Diet Score (adapted from Trichopoulou et al)
• Protective compounds: +1 if equal or above median intakeFruits and nuts, vegetables, legumes, fish, cereals, dairy products,
• Detrimental compounds: 0 if equal or above medianMeat
• Fat intake: Ratio of daily consumption of monounsaturated lipids to saturated lipids
• Not included in the index: Alcohol consumption
The INMA and Rhea Mother & Child Cohort Studies
Fetal Growth Assessment
Anthropometric measures at birth: Birth weight (BW), birth length (BL), head circumference (HC),
Fetal growth restriction: customized definition of impaired growth taking into account constitutional characteristics (gest age; parental anthropometry; primiparous mother; infant sex)
The INMA and Rhea Mother & Child Cohort Studies
Potential Confounders
Maternal, Paternal age, Maternal, Paternal social class and education, Maternal pre-pregnancy BMI (kg/m2), Maternal smoking during pregnancy, ParitySupplement use during pregnancy, Alcohol intake during pregnancy, Total Energy Intake during pregnancy
The INMA and Rhea Mother & Child Cohort Studies
Statistical analysis
The exposure variable of interest: Mediterranean Diet Score
The outcome variable of interest: Birth weight (BW), birth length (BL), head circumference (HC), and foetal growth restriction.
All variables related with the outcome in the bivariate models (p<0.2) were included in the multivariable models
Multivariable log-binomial and linear regression models performed after adjusting for confounders
Evaluation of effect modification (likelihood ratio test (a=0.1)
The INMA and Rhea Mother & Child Cohort Studies
Food groups intake during pregnancy
The INMA and Rhea Mother & Child Cohort Studies
0
100
200
300
400
500
600
Med
ian
inta
ke (
g/da
y)
Cer
eals
Veg
etab
les
Legu
mes
Fru
its a
nd n
uts
Fis
h an
d se
afoo
d
Mon
ouns
atur
ated
fatt
y ac
ids
Sat
urat
edfa
tty
acid
s
Dai
ry p
rodu
cts
Mea
t
INMA Atlantic INMA Mediterranean RHEA
Mediterranean Diet Score during pregnancy
The INMA and Rhea Mother & Child Cohort Studies
3.35
3.45
3.55
3.65
3.75
3.85
3.95
4.05
4.15
4.25M
ean (95% C
.I.)
0
5
10
15
20
25
30
35
40
45
50
Fre
quen
cy %
Diet Scoreof 0-3
Diet Scoreof 4-5
Diet Scoreof 6-8
INMAAtlantic
INMAMediterranean
RHEA
INMA Atlantic INMA Mediterranean RHEA
All models were adjusted for gender, gestational age, maternal smoking during pregnancy, maternal age and total energy intake using linear regression models.a P values for values for each component from the regression modelb Also adjusted for: INMA Atlantic: parity, maternal BMI, paternal education and parental social class; INMA Mediterranean: parity, parental BMI, and maternal social class; RHEA: maternal BMI and education.c Also adjusted for: INMA Atlantic: parity, maternal BMI, paternal age and maternal social class; INMA Mediterranean: parity, maternal BMI, and maternal social class; RHEA: maternal height and education.d Also adjusted for: INMA Atlantic: parity, maternal BMI and education; INMA Mediterranean: parity, maternal BMI, maternal education and alcohol intake; RHEA: maternal BMI and education.* Mediteranean Diet score, Low: 0-3; Medium: 4-5; High: 6-8
Associations between Mediterranean Diet Score in pregnancy with anthropometric measurements at
birth
The INMA and Rhea Mother & Child Cohort Studies
INMA Atlantic INMA Mediterranean RHEA
β SE Pa β SE Pa β SE Pa
Weightb
MD score, Low Ref. Ref. Ref.
MD score, Medium -26·46 26·03 0·310 55·20 23·52 0·019 -33·67 31·78 0·290
MD score, High -82·85 47·67 0·082 87·78 33·40 0·009 -20·42 42·33 0·630
Lengthc
MD score, Low Ref. Ref. Ref.
MD score, Medium -0·16 0·12 0·185 0·13 0·10 0·203 -0·43 0·18 0·077
MD score, High -0·25 0·22 0·245 0·30 0·15 0·040 -0·06 0·24 0·794
Head circumferenced
MD score, Low Ref. Ref. Ref.
MD score, Medium 0·03 0·09 0·770 0·03 0·07 0·647 -0·23 0·12 0·049
MD score, High -0·06 0·16 0·711 0·16 0·10 0·121 -0·20 0·16 0·214
Associations between Mediterranean Diet Score* in pregnancy with Foetal Growth Restriction (FGR)
The INMA and Rhea Mother & Child Cohort Studies
INMA Atlantic INMA Mediterranean RHEA
RR 95% CI Pa RR 95% CI Pa RR 95% CI Pa
FGR in Weightb
MD score, Low Ref Ref Ref
MD score, Medium 1·24 0·81, 1·89 0·329 0·76 0·54, 1·06 0·109 1·82 0·95, 3·49 0·071
MD score, High 0·97 0·42, 2·26 0·943 0·50 0·28, 0·90 0·021 1·96 0·90, 4·25 0·089
FGR in Lengthc
MD score, Low Ref Ref Ref
MD score, Medium 1·33 0·87, 2·04 0·189 1·01 0·70, 1·47 0·952 1·39 0·72, 2·68 0·330
MD score, High 0·63 0·23, 1·76 0·376 0·95 0·55, 1·62 0·838 0·90 0·35, 2·30 0·821
FGR in Head circumferenced
MD score, Low Ref Ref Ref
MD score, Medium 0·88 0·57, 1·34 0·543 1·15 0·80, 1·65 0·459 1·63 0·89, 2·96 0·112
MD score, High 1·11 0·53, 2·33 0·779 1·07 0·63, 1·83 0·800 1·64 0·76, 3·56 0·211
All models were adjusted for maternal smoking during pregnancy, maternal age and total energy intakea P values for each component from the log-binomial model.b Also adjusted for: INMA Atlantic: maternal social class; INMA Mediterranean: maternal BMI and maternal social class; RHEA: paternal age and maternal education.c Also adjusted for: INMA Atlantic and INMA Mediterranean: maternal education; RHEA: paternal education.d Also adjusted for: INMA Atlantic: paternal age, maternal BMI and education; INMA Mediterranean: maternal BMI, alcohol intake, education and social class; RHEA: maternal alcohol intake and education. * Mediteranean Diet score, Low: 0-3; Medium: 4-5; High: 6-8
Adjusted means of birth weight by Mediterranean Diet Score and maternal
smoking during pregnancy
The INMA and Rhea Mother & Child Cohort Studies
2950
3000
3050
3100
3150
3200
3250
MedDiet 0-3 MedDiet 4-6 MedDiet 6-8
We
igh
t (g
r)
INMA-Atlantic: Non Smokers (○), Smokers (●); INMA-Mediterannean: Non Smokers (□), Smokers (■); RHEA: Non Smokers (), Smokers (). All models were adjusted for maternal age and total energy intake, gender and gestational age. Models for weight were also adjusted for: INMA-Atlantic: parity, maternal BMI, paternal education and parental social class; INMA-Mediterannean: parity, parental BMI, and maternal social class; RHEA: maternal BMI and education.
Adjusted means of head circumference by Mediterranean Diet Score and maternal smoking
during pregnancy
The INMA and Rhea Mother & Child Cohort Studies
33.2
33.4
33.6
33.8
34.0
34.2
34.4
MedDiet 0-3 MedDiet 4-6 MedDiet 6-8
He
ad
circ
um
fere
nce
(cm
)
INMA-Atlantic: Non Smokers (○), Smokers (●); INMA-Mediterannean: Non Smokers (□), Smokers (■); RHEA: Non Smokers (), Smokers (). All models were adjusted for maternal age and total energy intake, gender and gestational age. Models for head circumference were also adjusted: INMA-Atlantic: parity, maternal BMI and education; INMA-Mediterranean: parity, maternal BMI, maternal education and alcohol intake; RHEA: maternal BMI and education.
Population based cohort design.
Customised definition of “foetal growth restriction”
Detailed data for dietary intake during pregnancy; Total energy intake
Multivariate analysis; exclusion criteria
Self-reported diet during pregnancy
Unknown confounding factors linked both with fetal growth and diet during pregnancy that could explain this association
Strengths Limitations
Strengths and limitations of the present study
Conclusions.. MD during pregnancy is not homogeneous within the Mediterranean area.
A high adherence to MD may modify the detrimental effectof smoking on birth size.
Complex underlying processes explain findings
The INMA and Rhea Mother & Child Cohort Studies
The Greek Mother & Child Cohort Study The Greek Mother & Child Cohort Study
to be continued ……………
To be continued…