reporter: but lina alvarez doesn't feel like a grandmother. e feels that it's a sign of progress to be able to have babies this way. lina: for heaven's sake, i don't know what's selfish about it. i'm just as much there for my children, and my experience is a great advantage. that speaks in favor of having children at my age. reporter: more and more women in spain are having babies later in life. private fertility clinics like this one in madrid charge around 8000 euros for the procedure. it involves implanting fertilized eggs from anonymous donors. but unlike other countries, spain sets no legal age limit. even so, doctors often refuse to perform the procedure on women over 50. they have even signed a voluntary agreement. antonio: of course we now have the ability to initiate pregnancies in women over 60. but we also want healthy children, and the probability of giving birth to a healthy child drops in women over age 50. reporter: legal expert carlos romeo casabona sees the voluntary agreement as useless. he's a member of the spanish commission