How can I access data about live birth by age group of mother in France, Germany, Italy and U.K?
Unfortunately, the IPUMS-International data on live births for the countries you have listed above is limited to Germany in 1970, 1971, and 1981. The variable CHBORN reports the number of children ever born to each woman of whom the question was asked. In 1970 and 1971, this question was limited to ever-married females and married females, respectively. In 1981, this question was asked of all females.
You can then either use the mother’s AGE variable to create age groups or use the pre-generated age groups available in the AGE2 variable. For more information on using the microdata available at the IPUMS-International website, see the online tutorials.
I hope this helps.