Pregnancy often exacerbates constipation in young women with chronic consti
pation syndromes. The presence of the fetus presents a challenge in both th
e diagnosis and treatment of these syndromes. This study was conducted to r
eport a rare case of idiopathic megarectum complicating a pregnancy. An agg
ressive polyethylene glycol (PEG) regimen allowed the patient to carry the
child to term and to have a normal vaginal delivery. Successful proctocolec
tomy was performed with coloanal anastomosis 3 months postpartum. The patie
nt has been free of constipation for 18 months without the need for cathart
ics or laxatives. All efforts to avoid operative intervention should be mad
e in constipated patients during pregnancy. This principle holds true even
in the setting of dilated large bowel. Idiopathic megarectum and the manage
ment of constipation in pregnancy are discussed. (Am J Gastroenterol 2000;9
5: 2969-2972. (C) 2000 by Am. Coll. of Gastroenterology).