Inclusion Criteria:

• Women greater than 18 years old with severe fibromyalgia and abnormally low IGF-1 levels included in a rehabilitation and psychological program and stable under standard intensive treatment for at least 6 months.
• All patients fulfilled the 1990 ACR diagnostic criteria (1) and had an IGF-1 level <250 ng/mL (or 1 standard deviation bellow the mean value corresponding to age and body surface according to laboratory reference value).
• Other inclusion criteria were duration of fibromyalgia of 1 year or greater, pain in at least 16 (8 bilateral) of the 18 tender points and a score in the FIQ > 75.
• The study was conducted in accordance with the Declaration of Helsinki and received the local institutional review board and Spanish Drug Agency (nº03-0456) approvals. All patients gave written informed consent prior to their inclusion in the study.

Exclusion Criteria:

• Disabling physical or mental status
• Previous or current malignancies, either active or inactive
• Intracranial space occupying lesion
• Any relevant endocrine disorder including diabetes mellitus
• History of another pituitary disorder
• Previous treatment with growth hormone
• Other systemic or joint inflammatory rheumatic conditions; and
• Known to be hypersensitive to somatropin or any of the excipients.
• Pregnant women, nursing mothers, or women with childbearing potential not using adequate contraceptive methods were also excluded.