Women postpone childbirth to an age when morbidity is higher and fertility has decreased and yet the knowledge of mothers' morbidity related to age remains scarce. Swedish national register data from the Medical Birth Register and National Patient Register was used to investigate the incidence of diseases listed in the International Classification of Diseases, version 10 (ICD-10) in women who gave birth 2007-8. The index group consisted of women 40 years of age or older (n?=?8 203) were compared to a control group of women, younger than 40 years (n?=?15 569) at childbirth. The period studied was five years before childbirth to five years after. The main outcome measures were incidence of disease diagnosed in specialized hospital care. Demographical data and use of assisted reproduction (ART) were adjusted for. The results showed that older women were more likely to be single; less frequently used tobacco; were educated on a higher level; had a higher BMI and more often had used ART to become pregnant. The older women showed a higher morbidity rate. In the diagnostic groups: Neoplasms, Blood and immune system, Eye and adnexa, Ear and mastoid, Circulatory, Digestive, Skin and subcutaneous tissue, Musculoskeletal and connective tissue, and Genitourinary. The results add to the body of knowledge of a number of specific risks faced by older mothers and may be used to identify preventive actions concerning fertility and morbidity both before and after childbirth.