Acromegaly and pregnancy: a prospective study

Context and objective: The interaction between pregnancy and acromegaly has been studied only retrospectively. We used prospective data to assess those interactions. Design: Prospective, interventional, multicentric study. Patients: Ten pregnancies in eight acromegalic patients were included according to the following criteria: previous diagnosis of acromegaly; and active acromegaly before pregnancy. Sellar magnetic resonance image (MRI), GH, and IGF1 measurements were carried out before pregnancy. The exclusion criterion was radiotherapy. Intervention: Withdrawal of pharmacological treatment (octreotide and/or cabergoline and/or pegvisomant) following pregnancy diagnosis. Main outcome measures: Clinical/biochemical evaluations throughout pregnancy/puerperium and sellar MRI after delivery; and GH and IGF1 measurements before pregnancy. GH was measured by an interference-free IFMA assay during pregnancy and IGF1 by measured by Immulite 2000 assay in patients and 64 control pregnancies. Results: No tumor growth was observed. Nine deliveries were at term and one at 35 weeks (preeclampsia). All newborns were healthy. Mean IGF1 levels before and during pregnancy were similar, but increased significantly during puerperium. As IGF1 in controls increased after midgestation, the prevalence of controlled IGF1 rose significantly from 2/10 (<20 weeks) to 9/10 (>30 weeks). Diabetes mellitus and hypertension/preeclampsia developed in one patient in each group; both complications were nonsignificantly (P=0.06) associated with IGF1 >1.3 ULN before pregnancy. Conclusions: Acromegaly control usually improved and tumor growth was not stimulated during pregnancy in spite of withdrawal of drug treatment. Drug treatment can be discontinued in most patients. Uncontrolled disease before pregnancy may pose a higher risk for diabetes and hypertension.