Joshua Nitsche1, Loralie J Langman2, Hannah J Penn2, Douglas Derleth3, William Watson4, Brian Brost4. 1. Division of Maternal Fetal Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina. 2. Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, Minnesota. 3. Department of Neonatology, Mayo Clinic College of Medicine, Rochester, Minnesota. 4. Division of Maternal Fetal Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota.
Abstract
OBJECTIVES: The aim of this study is to determine if maternal administration of acetaminophen affects fetal activity and thereby the interpretation of clinical assessments of fetal well being. STUDY DESIGN: A longitudinal study was performed in 20 women between 30 and 34 weeks' gestation with uncomplicated pregnancies. A 1-hour ultrasound was performed and recorded to document baseline fetal breathing and body movements. All the subjects were then given a 1,000 mg dose of oral acetaminophen. One hour later, a second 1 hour ultrasound was performed to document postacetaminophen fetal breathing and body movements. The number of episodes and total duration of gross body and fetal breathing movements were then assessed by a blinded observer. The pre- and post-acetaminophen values were compared using a repeated measures t-test. RESULTS: There was no significant effect of acetaminophen on the number of episodes or time spent in fetal breathing or body movements when each activity parameter was analyzed separately. In addition, there was no effect when fetal breathing and body movements were combined into a single composite activity score. CONCLUSION: Although acetaminophen has been shown to affect fetal activity in animal models, it has little effect on humans. Thus, maternal administration of acetaminophen should not affect assessment of fetal well being. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
OBJECTIVES: The aim of this study is to determine if maternal administration of acetaminophen affects fetal activity and thereby the interpretation of clinical assessments of fetal well being. STUDY DESIGN: A longitudinal study was performed in 20 women between 30 and 34 weeks' gestation with uncomplicated pregnancies. A 1-hour ultrasound was performed and recorded to document baseline fetal breathing and body movements. All the subjects were then given a 1,000 mg dose of oral acetaminophen. One hour later, a second 1 hour ultrasound was performed to document postacetaminophen fetal breathing and body movements. The number of episodes and total duration of gross body and fetal breathing movements were then assessed by a blinded observer. The pre- and post-acetaminophen values were compared using a repeated measures t-test. RESULTS: There was no significant effect of acetaminophen on the number of episodes or time spent in fetal breathing or body movements when each activity parameter was analyzed separately. In addition, there was no effect when fetal breathing and body movements were combined into a single composite activity score. CONCLUSION: Although acetaminophen has been shown to affect fetal activity in animal models, it has little effect on humans. Thus, maternal administration of acetaminophen should not affect assessment of fetal well being. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.