Vitamin D deficiency could be behind women's struggles to conceive with IVF, Perth research suggests

Vitamin D deficiency could be the reason behind some couples' struggles to conceive using IVF, according to new findings by Perth researchers.

Researchers at Curtin University tested the cells of 300 women undergoing the fertility treatment and found those who lacked sufficient levels of vitamin D were much less likely to develop a mature embryo.

"The women who had a sufficient level of vitamin D were actually 3.5-times more likely to develop a mature embryo," Nikita Walz, a Curtin University researcher, told 9News.

"These are much more likely to result in those clinical pregnancies."

Doctors aren't always able to determine the reasons behind a couple's infertility, with around 15 per cent of couples who undergo IVF not knowing why they can't fall pregnant without intervention.

Janita and Sam Burton were one such couple. It took them six years of IVF treatments before they conceived their daughter, Marni.

"From the testing they did, they weren't able to know why we were infertile," Ms Burton said.

One in six Australian couples require IVF to fall pregnant and researchers believe almost half of those women are vitamin D deficient.

"Between the age of 36 and 40 years old, the chances of getting a clinical pregnancy from an IVF cycle (is) around 30 to 35 per cent," said Ms Walz.

"So if we can have one cycle and have it successful, that would be absolutely amazing."

Researchers will now be investigating whether adding vitamin D supplements to the IVF process will improve the outcomes for patients.