Certain disorders treated with surgery are difficult to diagnose during pregnancy. A high level of suspicion is required; assuming that all abdominal symptoms are pregnancy-related is an error.
Major surgery, particularly intra-abdominal, increases risk of preterm labor and fetal death. However, surgery is tolerated well by pregnant women and the fetus when appropriate supportive care and anesthesia (maintaining BP and oxygenation at normal levels) are provided, so physicians should not be reluctant to operate; delaying treatment of a surgical emergency is far more dangerous.
Appendicitis
Appendicitis Appendicitis Appendicitis is acute inflammation of the vermiform appendix, typically resulting in abdominal pain, anorexia, and abdominal tenderness. Diagnosis is clinical, often supplemented by CT or ultrasonography... read more 
may occur during pregnancy but is more common immediately postpartum. Because the appendix rises in the abdomen as pregnancy progresses, pain and tenderness may not occur in the classic right lower quadrant location, and pain may be mild and cramping, mimicking pregnancy-related symptoms. Also, the white blood cell (WBC) count is normally somewhat elevated during pregnancy, making the WBC count even less useful than usual. Serial clinical assessment and compression-graded ultrasonography are useful.
Because diagnosis is often delayed, mortality rate from a ruptured appendix is increased during pregnancy and particularly postpartum. Thus, if appendicitis is suspected, surgical evaluation (laparoscopy or laparotomy depending on the stage of pregnancy) should proceed without delay.
Benign ovarian cysts
Benign ovarian cysts are common during pregnancy. Cysts that occur during the first 14 to 16 weeks are often corpus luteal cysts Functional ovarian cysts Benign ovarian masses include functional cysts (eg, corpus luteum cysts) and neoplasms (eg, benign teratomas). Most are asymptomatic; some cause pelvic pain. Evaluation includes pelvic examination... read more , which spontaneously resolve. Adnexal torsion Adnexal Torsion Adnexal torsion is twisting of the ovary and sometimes the fallopian tube, interrupting the arterial supply and causing ischemia. Symptoms include severe pelvic pain, often with nausea and vomiting... read more may occur. If adnexal torsion does not resolve, surgical therapy to unwind the adnexa or removal may be required. After 12 weeks, cysts become difficult to palpate because the ovaries, with the uterus, rise out of the pelvis.
Ovarian masses Benign Ovarian Masses Benign ovarian masses include functional cysts (eg, corpus luteum cysts) and neoplasms (eg, benign teratomas). Most are asymptomatic; some cause pelvic pain. Evaluation includes pelvic examination... read more are evaluated first by ultrasonography. Definitive evaluation (eg, excision) is delayed, if possible, until after 14 weeks unless any of the following occur:
The cyst enlarges continuously.
The cyst is tender.
The cyst has radiographic characteristics of cancer (eg, a solid component, surface excrescences, size > 6 cm, irregular shape).
Gallbladder disease
Gallbladder disease Overview of Biliary Function The liver produces about 500 to 600 mL of bile each day. Bile is isosmotic with plasma and consists primarily of water and electrolytes but also organic compounds: bile salts, phospholipids... read more occurs occasionally during pregnancy. If possible, treatment is expectant; if women do not improve, surgery is needed.
Intestinal obstruction
During pregnancy, intestinal obstruction Intestinal Obstruction Intestinal obstruction is significant mechanical impairment or complete arrest of the passage of contents through the intestine due to pathology that causes blockage of the bowel. Symptoms include... read more 
may cause intestinal gangrene with peritonitis and maternal or fetal morbidity or mortality. If pregnant women have symptoms and signs of intestinal obstruction and risk factors (eg, previous abdominal surgery, intra-abdominal infection), prompt exploratory laparotomy is indicated.
