Pregnancy and Breastfeeding during Intrathecal Baclofen Therapy – A Case Study and Review

We report the case of a young woman who received intrathecal baclofen therapy (ITB) and subsequently became pregnant and had a normal delivery. A 28-year-old woman with flexion myelopathy had anterior decompression with fusion at C4/5 and C5/6 levels. Clinical symptoms improved after surgery. However, when she was 29 years old, her symptoms steadily advanced to Modified Ashworth Scale 3 spasticity level in the lower legs, with pain in both of them and urinary retention tendency. Since a 25 μg intrathecal baclofen injection improved her symptoms, an ITB pump system was implanted. After surgery, lower limb spasticity and urinary retention improved. Two years after ITB pump implantation, the patient married and became pregnant. The patient intended to have normal delivery but the induction of labor was ineffective and childbirth was completed by Cesarean section with lumbar anesthesia. The infant’s Apgar score was 8 at 1 min and 9 at 5 min, and birth-weight was 2,704 g. We measured the baclofen concentration in the patient’s breast milk using high-performance liquid chromatography/tandem mass spectrometry. The level of baclofen in the breast milk was very low (0.617 ng/ml) and the predicted pharmacological effect on the infant was judged to be negligible. No withdrawal symptoms or muscle tone abnormalities were found after birth. Our findings indicate that ITB therapy could be considered for young women with severe spasticity, even if they plan to have children.