Fergie and her actor husband Josh Duhamel were delighted when they discovered the singer was pregnant because they had been trying for a baby for "quite a while".

The 38-year-old hitmaker, who announced her baby news in February (13), recently revealed she had planned her pregnancy to coincide with the Black Eyed Peas' hiatus following the end of their world tour in 2011, but Duhamel admits conceiving a child took a little longer than expected.

He says, "We've been trying for the last year or so. We've been trying for this for quite a while."

Duhamel insists he will be right by his wife's side when Fergie goes into labour, but he must obey one key rule in the delivery room.

He tells U.S. talk show host Chelsea Handler, "I will be there (in the delivery room). She says that I can't be anywhere below (her chest). You know, because some women get nervous about the actual birthing process... But for me, I think it's a beautiful thing."