Sarah Jessica Parker has confirmed that she and husband Matthew Broderick only decided to have a baby with the help of surrogate because she had problems conceiving herself.

The Sex and the City star gave birth to son James Wilkie in 2002 but earlier this month, she and Matthew announced that they are expecting twins through a surrogate later this year.

Speaking to Access Hollywood recently, she said: “We have been trying to expand our family for a number of years and we actually have explored a variety of ways of doing so.

“[Using a surrogate] would have been odd to have made this choice if I was able to have had successful pregnancies since my son’s birth.”

She added that the couple have been working hard to prepare six year old James for the arrival of his younger sisters: “I’ve been pretty candid with him. I wanted him to have time to adjust to the idea of sharing his mama and his papa.”