Rod Stewart's doctor banned him from wearing tight trousers so he could father another child.

The 'Maggie May' rocker - who has eight children from various relationships - and wife Penny Lancaster were struggling to conceive for the second time, but the model fell pregnant after her 70-year-old spouse ditched his close-fitting clothes.

Penny - who has sons Alistair, nine, and Aiden, four, with Rod - said: ''What separates them from us is their baby-making ability of having the sperm and when Rod and I were trying to make our second child we were having a few troubles and a doctor said, 'Rod, you've got to forget wearing the tight pants and the trousers, OK? Get rid of the Calvin Kleins, do the loose boxer shorts, no hot baths.''

And Penny - who previously suggested men shouldn't be expected to cook for their families - even claimed guys should stay out of the kitchen for fertility reasons.

She added during an appearance on 'Loose Women': ''Then I spoke with a very famous celebrity chef, who said he was having similar issues trying to produce a baby and they had told him one of the problems is because you are standing by the oven, and men are designed the way they are, to keep it on the outside of the body, to keep them cool and when they are standing there by the oven, they are heating them up.

''So anyone out there, any men, don't use this as an excuse necessarily but if you're trying to make a baby and are having problems, don't go near the oven!''