Fresh fruits and vegetables consumed in the three months before pregnancy reduce the chance of having a small for

Published on 10/06/10

A BJOG study reveals the key risk factors associated with babies being born undernourished or small for gestational age (SGA). Findings reinforce the importance of eating a balanced diet before and during pregnancy, with consumption of fresh fruit and vegetables being associated with better outcomes for the baby.

The study: McCowan L, Roberts C, Dekker G, Taylor R, Chan E, Kenny L, Baker P, Moss-Morris R, Chappell L, North R. Risk factors for small-for-gestational-age infants by customised birthweight centiles: data from an international prospective cohort study. BJOG 2010; DOI: 10.1111/j.1471-0528.2010.02737.x.
 

The SCOPE (Screening for Pregnancy Endpoints) study comprises a large database of pregnant women from four different countries (New Zealand, Australia, Ireland, UK). It aims to develop screening tests for pre-eclampsia, SGA infants and spontaneous preterm births. In this particular study, researchers looked at the outcomes associated with the two main groups of SGA infants: those who had mothers with normal blood pressure and those whose mothers had high blood pressure in late pregnancy.

3,513 nulliparous women with singleton pregnancies were identified and participated in the study between November 2004 and August 2008. They were interviewed at 15 ± 1 weeks of gestation and underwent ultrasound scans at 20 ± 1 weeks when fetal growth measurements were taken and Doppler ultrasound studies on their umbilical and uterine arteries were performed. Detailed demographic data were collected and examined including the woman’s own birthweight, her gynaecological history, socio-economic status, smoking history and alcohol consumption and diet.

Researchers found that a woman’s diet, prior to conception, had a strong influence on the risk of normotensive (normal blood pressure) SGA. Women who consumed a high intake of green leafy vegetables (defined as ≥ three portions of vegetables a day) were found to have a 50% reduction in SGA babies. Those consuming low amounts of fruit (defined as < one portion a week) had a 50% increase in SGA babies. Researchers believe that the nutrients found in fruits and vegetables may be protective to the pregnant mother and the developing fetus but concede that women who consume high amounts of such foods may also lead healthier lifestyles generally. Similarly, those with a high intake of oily fish (≥ 3 servings per week) had a 60% reduction in SGA babies. The authors suggest that their findings on dietary intake may have important public health implications. Pregnancy, and where possible prior to the pregnancy, may well be the ideal times to encourage women to adopt a healthy diet, improve their intake of important nutrients, and make lifestyle changes to reduce their risk of obesity.

Other findings include: cigarette smoking at 15 weeks which was associated with a 30-60% increase in risk of SGA for every five cigarettes smoked per day. Previous work by the same group has recently demonstrated that this risk of SGA due to smoking can be avoided completely provided that the mother stops smoking before the 15th week of pregnancy.

Professor Lesley McCowan Head of the Department of Obstetrics and Gynaecology, University of Auckland, who led this study, said “SGA infants are more likely to be stillborn, to have complications in the newborn period and in later life. Less than one third of these at-risk babies are identified before birth in current antenatal practice. Improved identification of these vulnerable infants, by screening early in pregnancy, therefore has the potential to reduce stillbirths and complications in the newborn period.

“In the SCOPE study, our findings show that the risk factors for the majority group of SGA infants with mothers with normal blood pressure included: low fruit intake (less than weekly) in the three months before pregnancy, cigarette smoking, increasing maternal age, daily vigorous (high intensity) exercise, being a tertiary student, and the pregnant woman being born with a low birthweight herself. Eating green leafy vegetables three or more times daily in the three months before pregnancy reduced the risk by 50% as did having a Rhesus negative blood group. Risk factors for SGA infants in mothers with high blood pressure included conception by in vitro fertilisation and previous early pregnancy loss.

“These findings emphasise the influence of pre-pregnancy diet on the baby’s growth and are important as a number of the identified risk factors are amenable to public health interventions.”

Professor Philip Steer, BJOG editor-in-chief, said “The importance of taking up and maintaining a healthy lifestyle before and during pregnancy has repeatedly been shown, however we live in an era of fast and convenience foods which are attractive but bad for our health if eaten too often and to the exclusion of healthier options. This study emphasises the importance of good diet and nutrition. Unfortunately, many people find it difficult to resist the temptations of ‘junk’ food.

“If more women can be persuaded to have a better diet during pregnancy, using the motivation of optimising their baby’s health, then as they are commonly in charge of the family diet, we could improve the health of the whole population. The take-home message is: Fewer take-aways, more fresh fruit and vegetables.”

The study: McCowan L, Roberts C, Dekker G, Taylor R, Chan E, Kenny L, Baker P, Moss-Morris R, Chappell L, North R. Risk factors for small-for-gestational-age infants by customised birthweight centiles: data from an international prospective cohort study. BJOG 2010; DOI: 10.1111/j.1471-0528.2010.02737.x.
 

 

RCOG Fellows and Members:

Have you logged in? If not, please log in. Once logged in, this study can be found in the list of Early View Articles.
 

 

Bookmark and Share

Search the Site

Search

 

 

 

 

 

SCImago Journal & Country Rank