Researchers have found that women who follow a Mediterranean diet in the six months before assisted reproductive treatment have a significantly better chance of becoming pregnant and giving birth to a baby than women who did not.

According to the researchers, they asked women about their diet before they underwent in vitro fertilisation (IVF) treatment and found that those who ate more fresh vegetables, fruit, whole grains, legumes, fish and olive oil, and less red meat, had a 65-68 per cent greater likelihood of achieving a successful pregnancy and birth compared to women with the lowest adherence to the Mediterranean-style diet.

"The important message from our study is that women attempting fertility should be encouraged to eat a healthy diet, such as the Mediterranean diet, because greater adherence to this healthy dietary pattern may help increase the chances of successful pregnancy and delivering a live baby," said Nikos Yiannakouris, Assistant Professor at Harokopio University of Athens.

The study, published in the journal Human Reproduction, focused on dietary patterns rather than individual nutrients, foods or food groups. It assessed the diet of 244 women via a food frequency questionnaire for their first IVF treatment. The questionnaire asked them about how often they ate certain groups of food in the preceding six months; the results gave the women a MedDiet Score, which ranged from 0-55 with higher scores indicating greater adherence to the Mediterranean diet.

The women were aged between 22-41 and were non-obese (body mass index of less than 30 kg/m²). Researchers divided the women into three groups depending on their MedDiet Score: the first group had scores between 18 to 30, the second scored between 31 to 35 and the third group scored between 36 to 47.

They found that compared to the 86 women in the highest scoring group, the 79 women in the lowest scoring group had significantly lower rates of pregnancies (29 per cent versus 50 per cent) and live births (26.6 per cent versus 48.8 per cent).

When the researchers looked at women younger than 35 years old, they found that every five-point improvement in the MedDiet Score was linked with an approximately 2.7 times higher likelihood of achieving a successful pregnancy and live birth.

Overall, 229 women (93.9 per cent) had at least one embryo transferred to their wombs; 138 (56 per cent) had a successful implantation; 104 (42.6 per cent) achieved a clinical pregnancy (one that can be confirmed by ultrasound); and 99 (40.5 per cent) gave birth to a live baby. "It should be noted that when it comes to conceiving a baby, diet and lifestyle are just as important for men as for women," Yiannakouris said.