Inclusion Criteria:  pregnant women, age 18 years or older, admitted to the University Hospital Centre Zagreb, Zagreb, Croatia, with the suspicion of acute appendicitis, from January 2010 to December 2020.  Exclusion Criteria:  non-pregnant patients pregnant patients younger than 18 years diagnosis made with CT or MRI pregnant patients with the acute abdomen (intraoperative diffuse peritonitis) from acute appendicitis