The study, published in the American Journal of Clinical Nutrition, analysed the diets of nearly 3,500 women and found high consumption of carrots, cauliflower, broccoli, pumpkin, cabbage, green beans and potatoes before conception helped women reach full-term pregnancy.
"The findings suggested dietary intervention and strategies change behaviour may be helpful when women start thinking about having a baby," said study researcher Gita Mishra, Professor at the University of Queensland in Australia.
"People born prematurely face a greater risk of metabolic and chronic diseases in adulthood, as well as poor cognitive development and academic performance," Professor Mishra said.
According to the researchers, premature births, which are births before 37 weeks of gestation, is the leading cause of death in Australian children and affect 8.5 per cent of births each year, a figure which is trending upwards.
Findings from previous studies on associations between prepregnancy dietary patterns and preterm birth and low birth weight (LBW) are limited and inconsistent.
The researchers wanted to examine the association between prepregnancy dietary patterns and the risk of preterm birth and low birth weight.
They found that greater adherence to the traditional vegetable pattern before pregnancy was associated with a lower risk of preterm birth.
"Traditional vegetables are rich in antioxidants or anti-inflammatory nutrients, which have a significant role in reducing the risk of adverse birth outcomes," said study researcher Dereje G Gete.
Women depend on certain stored nutrients such as calcium and iron before conception, which are critical for the placenta and foetus tissue development, according to the researchers.
"Starting a healthier diet after the baby has been conceived may be too late because babies are fully formed by the end of the first trimester," he noted.