Management of PregnantPatients Undergoing

General Surgical Procedures

Melissa K. Stewart, MD, Kyla P. Terhune, MD*

KEYWORDS

� Pregnancy � Nonobstetric surgery � Perioperative care

KEY POINTS

� Physiologic changes during pregnancy span almost every organ system, influencing evenlaboratory values of pregnant patients, and must be understood in order to optimize peri-operative and operative care.

� Diagnostic modalities are necessary but can have effects on fetuses and should be under-stood in order to minimize radiation exposure during pregnancy.

� Most preoperative considerations for pregnant patients are similar to those for nonpreg-nant patients; however, a basic knowledge of medications and anesthetic considerationsis important in order to provide safe care.

� Surgical patients are surgical patients, whether pregnant or not. Surgical issues must beaddressed, and delay of operative care can lead to worsened outcomes, despite gesta-tional status and stage.

INTRODUCTION

Of women of reproductive age, 102.1 per 1000women are pregnant in the United Statesatanygiven time.1Of thosewhoarepregnant, approximately 0.2%to0.75%requirenon-obstetric surgical intervention during pregnancy.2,3 As in the general surgery population,the most common presenting conditions requiring nonobstetric operations during preg-nancy are appendicitis and cholecystitis.4 In general, the approach is the same: toaddress the surgical issue. However, there are a multitude of additional considerationsfor pregnant patients, one of which is recognizing the importance of multidisciplinarycare. As stated in an American Congress of Obstetrics and Gynecology opinion in2011, the management of a pregnant patient should bemultifaceted, involving the coor-dination of the obstetrician, surgeon, anesthesiologist, and neonatologist, because con-cerns regarding both the fetus and the mother may require management modification.5

Disclosures: The authors have no financial disclosures.Department of Surgery, Vanderbilt University Medical Center, 1161 21st Avenue South, Nash-ville, TN 37232, USA* Corresponding author. D-4309 MCN, 1161 21st Avenue South, Nashville, TN 37232.E-mail address: kyla.terhune@vanderbilt.edu

Surg Clin N Am 95 (2015) 429–442http://dx.doi.org/10.1016/j.suc.2014.10.007 surgical.theclinics.com0039-6109/15/$ – see front matter Published by Elsevier Inc.

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PHYSIOLOGIC CHANGES IN PREGNANCY

Physiologic changes during pregnancy are numerous and span most organ systems(Fig. 1). By recognizing and understanding these changes, surgeons may optimize

Fig. 1. Physiologic changes during pregnancy by system. BUN, blood urea nitrogen; FRC,functional residual capacity; GFR, glomerular filtration rate; IVC, inferior vena cava; RV,residual volume; TLC, total lung capacity.

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perioperative and intraoperative management. Each affected organ system is dis-cussed separately later.

Cardiovascular System

With expansion of the gravid uterus and subsequent increased intra-abdominal pres-sure, the diaphragm is upwardly displaced and rib shape is changed. This changeleads to longitudinal rotation and lateral displacement of the heart, which can resultin false radiographic findings that suggest cardiomegaly.The heart develops eccentric hypertrophy secondary to increased blood volume.

This increased blood volume increases the cardiac output by increasing stroke vol-ume. When combined with concomitant increased heart rate, cardiac output can in-crease by 30% to 50% in pregnant patients, peaking at 25 to 30 weeks’ gestation.Despite this increase in cardiac output, maternal blood pressure is decreased second-ary to decreased systemic vascular resistance. In addition, all of these balanced dy-namics can be markedly affected by positional changes, most of which can beaccounted for by inferior vena cava compression by the gravid uterus.6,7

Respiratory Changes

As in most systems, the respiratory effects are a combination of hormonal and me-chanical changes. Increased estrogen causes the mucosa of the nasopharynx tobecome edematous and hyperemic, leading to both hypersecretion and an increasedlikelihood of spontaneous or induced epistaxis. Relaxation of the cartilaginous attach-ments between the ribs and sternum, as well as mechanical pressure from the graviduterus, leads to structural changes of the thoracic cavity, including an increase in sub-costal angle, increased chest diameter, and rise in the diaphragm. These changesresult in decreased total lung capacity, decreased functional residual capacity, anddecreased residual volume. In addition, secondary to progesterone, an increased res-piratory rate occurs. Combined with decreased capacities and volumes, this results inincreased alveolar ventilation and a chronic respiratory alkalosis.6,7

Hematologic Changes

Changes in maternal blood volume begin to occur as early as the first month of preg-nancy. Throughout the pregnancy, blood volume increases progressively, expandingby 40% to 50%, until about 30 to 34 weeks’ gestation. Erythrocyte mass also in-creases by approximately 30%. The differential increase in blood volume versus eryth-rocyte mass leads to an overall net decrease in hematocrit; a condition that is calledphysiologic anemia of pregnancy.The white blood cell count also progressively increases. The cause of this leukocy-

tosis is unclear but may be related to increased cortisol and estrogen levels. Moreover,because of relative venous stasis secondary to compression of the inferior vena cavaand concomitant hypercoagulability secondary to an increase in procoagulants, astate thought to be protective against peripartum hemorrhage, pregnancy results ina 5-fold to 6-fold increased risk of thromboembolic events.6,7

Gastrointestinal Changes

Secondary to relaxant effects of estrogen and progesterone on smooth muscle, thetone and the motility of the esophagus and stomach are decreased. This change, inconjunction with mechanical gastric compression from an enlarged uterus, leads toa marked increase in gastroesophageal reflux during pregnancy. Approximately30% to 50% of pregnant women report having dyspepsia and reflux. In addition,30% to 40% complain of changes in bowel habits, ranging from constipation to

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diarrhea. Similar to the alimentary tract, the gallbladder is affected by hormone-induced changes. Such changes lead to decreased ejection fraction and increasedbiliary cholesterol saturation, making biliary sludge and stones more likely.6,7

Renal/Urinary Changes

The kidney and renal collection system increase in size during pregnancy with dilata-tion of the renal pelvis, calyces, and ureters. Renal plasma flow and, subsequently,glomerular filtration rate are markedly increased during pregnancy; nearly 50% withinthe first trimester alone. This hyperfiltration leads to a physiologic decrease in serumcreatinine level, blood urea nitrogen level, and uric acid concentration. Other anatomicchanges include increase in the bladder trigone and potentially increased vascular tor-tuosity resulting in increased microhematuria. Also of note, secondary to outwardpressure by the expanding uterus, bladder capacitance decreases over time, resultingin urinary frequency, urgency, and incontinence.6,7

PREOPERATIVE EVALUATION

A principle that underpins the work-up of a patient was aptly stated by Sir ZacharyCope: “Earlier diagnosis means better prognosis.”8 This mantra holds true especiallyin pregnancy, in relation to both the prognosis of the mother and fetus. For example,36% of women with perforated appendicitis, which can often be attributed to delayeddiagnosis, experience fetal loss, compared with 1.5% to 9% in those with nonperfo-rated appendicitis.9

Although the evaluation of pregnant patients carries a unique set of dilemmas, thework-up should be initiated in the same manner as that of nonpregnant patients,beginning with a detailed history and physical examination. In the physical examina-tion, the clinician must consider that the organ in question, such as the appendix,may be significantly displaced secondary to the gravid uterus. Subsequently, the clini-cian must carefully consider the use of adjunctive diagnostic modalities, because ef-fects on both the patient and fetus must be considered. Evaluation by both laboratoryand radiographic techniques, with accompanying description of the modality and spe-cific risks/benefits, are described later.

Biochemical Evaluation

Based on the anatomic and physiologic changes described earlier, altered laboratoryvalues may be seen in pregnant patients compared with normal values.10 A summa-rization of these changes is shown in Table 1.11

Imaging Techniques

Computed tomographyComputed tomography (CT) uses ionizing radiation: high-energy photons capable ofdamaging DNA and generating caustic free radicals (summarized in Table 2).12 Giventhis, fetal exposure carries potential risks of gene mutations, which could lead to tera-togenesis or malignancy. Although causality has been established in the literature,the risk remains small. Most usual diagnostic examinations used in the work-up ofgeneral surgical patients (ie, CT abdomen, CT pelvis, and CT pyelogram) are allbelow the proposed maximum radiation level.13 As stated by the American Collegeof Radiology, “No single diagnostic procedure results in a radiation dose thatthreatens the well-being of the developing embryo and fetus.”12 Note that the effectis cumulative, and the recommended level of exposure to the fetus should notexceed 5 rad.14

Table 1Summary of expected laboratory values during pregnancy across trimesters

NonpregnantFirstTrimester

SecondTrimester

ThirdTrimester

Complete Blood Count

Hemoglobin (g/dL) 12.0–15.8 11.6–13.9 9.7–14.8 9.5–15.0

Hematocrit (%) 35.4–44.4 31.0–41.0 30.0–39.0 28.0–40.0

Platelet (�109/L) 165–415 174–391 155–409 146–429

White blood cell count (�103/mm3) 3.5–9.1 5.7–13.6 5.6–14.8 5.9–16.9

Coagulation Profile

Prothrombin time (s) 12.7–15.4 9.7–13.5 9.5–13.4 9.6–12.9

International Normalized Ratio 0.9–1.04 0.85–1.08 0.83–1.02 0,80–1.09

Partial thromboplastin time (s) 26.3–39.4 23–38.9 22.9–38.1 22.6–35.0

Complete Metabolic Panel

Sodium (mEq/L) 136–146 133–148 129–148 130–148

Potassium (mEq/L) 3.5–5.0 3.6–5.0 3.3–5.0 3.3–5.1

Chloride (mEq/L) 102–109 101–105 97–109 97–109

Bicarbonate (mmol/L) 22–30 20–24 20–24 20–24

Urea nitrogen (mg/dL) 7–20 7–12 3–13 3–11

Creatinine (mg/dL) 0.5–0.9 0.4–0.7 0.4–0.8 0.4–0.9

Alanine transaminase (U/L) 7–41 3–30 2–33 2–25

Aspartate transaminase (U/L) 12–38 2023 3–33 4–32

Bilirubin, total (mg/dL) 0.3–4.8 0–4.9 0–9.1 0–11.3

Bilirubin, unconjugated (mg/dL) 0.2–0.9 0.1–0.5 0.1–0.4 0.1–0.5

Bilirubin, conjugated (mg/dL) 0.1–0.4 0–0.1 0–9.1 0–0.1

Alkaline phosphatase (U/L) 33–96 17–88 25–126 38–229

Amylase (U/L) 20–96 24–83 16–73 15–81

Lipase (U/L) 3–43 21–76 26–100 41–112

Magnesium (mg/dL) 1.5–2.3 1.6–2.2 1.5–2.2 1.1–2.2

Phosphate (mg/dL) 2.4–4.3 3.1–4.6 2.5–4.6 2.8–4.6

Data from Cunningham F. Normal reference ranges for laboratory values in pregnancy. In: Post TW,editor. UpToDate; 2014. [cited August 1, 2014].

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UltrasonographySound waves, not ionizing radiation, are used in ultrasonography. These wavesare generally thought to be safe to the fetus. Although no documentation of adversefetal effects from diagnostic ultrasonography procedures exists, the US Food andDrug Administration recommends limiting ultrasonography energy exposure to

Table 2Summary of imaging modalities

Modality Risk Potential Effects Limit

Radiograph,fluoroscopy, CT

Ionizing radiation Gene mutation Teratogenesis,malignancy

5 rad

Ultrasonography Sound waves — — 94 mW/cm2

MRI Magnetic energy Acoustic noise, heat — —

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94 mW/cm2.15 Because of the improved safety profile of ultrasonography, it hasgained popularity and largely replaced radiographic diagnostic modalities usingionizing radiation.16 However, it is limited by body habitus and can be highly operatordependent. Hence, reliability and precision may be decreased. For example, in multi-ple studies analyzing identification of acute appendicitis during pregnancy with theuse of ultrasonography, sensitivities ranged from 50% to 100% and specificity from96% to 100%.17–19 These values are markedly less than the nearly 98% sensitivity,specificity, and diagnostic accuracy of CT and MRI.20,21

MRILike ultrasonography, MRI provides a nonionizing radiation imaging alternative. MRIuses magnetic energy to alter the state of hydrogen protons.16 Although it is postu-lated that the acoustic noise and heat produced may be detrimental to a developingfetus, no specific adverse fetal effects of MRI have been reported.22,23 Although fetaleffects have yet to be elucidated, intravenous gadolinium agents, which are used toincrease definition in certain MRI studies, can cross the placenta.24 Because of thisand the potential risk of nephrogenic systemic fibrosis, its use is not recommendedin pregnant patients.25

Cholangiography: intraoperative and endoscopic retrogradecholangiopancreatographyThe potential ill effects of cholangiography are secondary to radiation exposure.Typical intraoperative cholangiography exposure is estimated to be between 0.2and 0.5 rad/s.26 It is recommended that the fetus be shielded by placing a protectivebarrier between the patient and the radiation source. In fluoroscopy, this radiationsource is generally beneath the operating table, necessitating the placement of leaddirectly on the table and the patient on the lead. This placement is not instinctivebecause the tendency is to cover the patient with lead, which would provide no pro-tection. Other methods of protection should also be used. Rather than using so-calledlive fluoroscopy, clinicians could inject the contrast agent and obtain a single comple-tion cholangiogram, thus minimizing radiation exposure. Endoscopic retrograde chol-angiopancreatography (ERCP) radiation exposure can be significantly higher than thatof intraoperative cholangiography, averaging between 2 and 12 rad/s.27 Moreover,ERCP carries the additional risks of bleeding and pancreatitis.In summary, the same potential diagnostic studies are available to pregnant patients

and should be used when necessary. When deciding on a modality, clinicians mustconsider the risks and benefits. The risk of a missed or incorrect diagnosis almostalways outweighs the risk of any of the aforementioned studies. It is of utmost impor-tance that physicians communicate said risks to their patients, allowing an active,informed conversation and joint decision making.

PATIENT SELECTION/PREOPERATIVE PREPARATION

If a condition requiring surgical intervention is diagnosed, such as appendicitis orcholecystitis, an urgent operation should be performed regardless of the trimester.In contrast, if a condition is deemed elective, it should be scheduled for after delivery,when the impact to the fetus is no longer a concern. This timing confers the addedadvantage of maternal physiology returning to normalcy. If a condition is deemednecessary but semielective, the second trimester is considered the safest time.5

This recommendation stems from a multitude of available data. During the secondtrimester, after organ system differentiation has occurred, the risk for anesthetic-induced malformation or spontaneous abortion declines significantly.28 Although the

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differential between first and second trimesters is genetically based, the preferencefor second versus third trimester is mechanically based. In the second trimester, theuterus size does not greatly crowd the abdominal operative domain. Moreover, therisk of preterm labor is lower during the second trimester.4 Specific preoperativeconsiderations include the following.

Fasting Guidelines/Aspiration Precautions

Based on guidelines presented by the American Society of Anesthesiologist TaskForce on Obstetric Anesthesia in 2007, the fasting guidelines for pregnant patientsmimic the guidelines set forth for standard adults. Recommendations suggestabstaining from solids for at least 6 hours before surgery and from clear liquids forat least 2 hours before surgery.29 Although it is known that the incidence of gastro-esophageal reflux is increased in pregnancy, no specific intervention has been shownto improve clinical outcomes with regard to aspiration prevention. However, most pro-viders practice rapid sequence intubation to minimize the risk of aspiration.30

Thromboprophylaxis

As described earlier, the risk of thromboembolic events is markedly increased duringpregnancy. The American College of Chest Physicians recommends mechanical and/or pharmacologic thromboprophylaxis for all pregnant patients undergoing an opera-tion. Low-molecular-weight heparin is the recommended modality and is a safe drugchoice during pregnancy. Early mobilization should be encouraged, and prophylaxisshould be continued until the patient is mobilized postoperatively.31

Antibiotic Prophylaxis

The need for antibiotic prophylaxis during pregnancy depends on the specific opera-tive procedure and is similar to the guidelines set forth for standard surgical patients.In generic terms, penicillins, cephalosporins, azithromycin, clindamycin, and erythro-mycin have good safety profiles. However, there are some classes of antibiotics toavoid. Aminoglycosides carry a risk of fetal and maternal ototoxicity and nephrotoxi-city. Tetracyclines have been associated with suppression of bone growth and stain-ing of developing teeth in fetuses. Fluoroquinolones are known to have toxic effects ondeveloping cartilage. Given the possible toxicities described earlier, before antibioticprescription, the specific safety profile must be explored and understood, and phar-macologic consultation obtained if needed.28

Preterm Labor Prophylaxis: Glucocorticoids and Tocolytics

Preterm labor risk in the perioperative period is notably increased. If preterm birth isanticipated or deemed a high risk, and the fetus is deemed potentially viable, prophy-laxis with glucocorticoids should be considered. If preterm labor occurs, administra-tion of glucocorticoids 24 to 48 hours before surgery markedly reduces perinatalmorbidity and mortality. However, antenatal glucocorticoids may impair the maternalimmune response to the underlying disorder. Consultation should be obtained from anobstetrics service to help project the risk of preterm birth. Prophylactic use of tocolyticagents has not proved to be beneficial.32–36 From a physical standpoint, minimizinguterine manipulation may reduce the risk of uterine contraction and subsequent pre-term labor.37,38

ANESTHESIA

Plausible risks of anesthesia to fetuses include direct teratogenic effects of medica-tions and anesthetic agents, decreased uteroplacental blood flow secondary to

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changing maternal physiology, and preterm labor. Although this list is not complete,basic anesthetic considerations are discussed later.

Positioning

Secondary to possible hemodynamic consequences of vena cava compression froman enlarged uterus, it is recommended that pregnant patients be positioned with a15% left lateral tilt when possible.28,39,40

Fetal Heart Rate Monitoring

Coordinating obstetricians and neonatologists can be helpful in determining the needand technique for fetal monitoring. The American College of Obstetricians and Gyne-cologists has stated that the decision to use intermittent or continuous intraoperativefetal monitoring should be based on the type of surgery, available resources, andgestational age. During the first and early second trimester, fetal heart tones aretypically monitored before and after anesthesia exposure and operative intervention,but not during the case. During the late second and third trimester, secondary tothe viability of the fetus, continuous intraoperative fetal monitoring via transabdominalultrasonography is generally used. If the surgical field involves the abdomen, transva-ginal ultrasonography can be used.16 Despite this recommendation, multiple studieshave shown that it is likely unnecessary to use continuous monitoring, because therisk of ill effect and/or the need for intervention is minimal.28,41

Type of Anesthetic

Decisions regarding the type of anesthetic to be used should involve consideration ofthe planned intervention, the projected risk of maternal physiologic changes, and thepredicted teratogenesis. Despite this recommendation, no studies exist that show asignificant difference in outcomes. Choices and considerations based on our physio-logic understanding of the effects are listed here:

Monitored anesthesia careMonitored anesthesia care (MAC) involves intermittent administration of analgesicsand anxiolytics, combined with continuous monitoring of the patient. Much of theconcern surrounding the use of MAC during pregnancy is derived from the possibilityof induced hypoventilation with subsequent acidosis and decreased placental circu-lation. The risk of aspiration secondary to positioning and induced smooth musclerelaxation may also be increased.42 However, because most operations completedduring pregnancy are intra-abdominal, the use of MAC is generally not an option.

Regional anesthesiaRegional anesthesia via peripheral nerve and neuroaxial blocks is considered safeduring pregnancy. Such blocks are particularly useful and encouraged during extrem-ity operations. Moreover, neuroaxial blocks may be used for surgery of the lowerabdomen, pelvis, and lower extremities. If neuroaxial blocks are used, the providermust be cautious of the potential for induced maternal hypotension from a sympa-thetic block. Systemic hypotension can lead to reduction in placental perfusion andsubsequent fetal compromise.42

General anesthesiaAs noted earlier, most operations performed during pregnancy involve laparoscopyor laparotomy, thus requiring general anesthesia. Anesthesia induction involvespreoxygenation, medication administration (anesthesia/analgesia/paralytic), and intu-bation. Preoxygenation is vital in pregnant patients, because hypoxia can lead to

Management of Pregnant Patients 437

compromised placental blood flow. Per the physiologic discussion earlier, pregnantpatients have less reserve and can desaturate in less time than nonpregnant women.43

Once preoxygenation is complete, propofol is generally used as the induction agentof choice, although no induction agent has been shown to be teratogenic. Hemody-namic effects of induction must be anticipated and mitigated in order to maintainplacental blood flow.28

For muscle relaxation, nondepolarizing neuromuscular blocking agents are thoughtto be safe, because they do not cross the placenta. Succinylcholine is the medicationmost often used, because it facilitates rapid sequence intubation (RSI).28 Despitethese general practices, no data have shown differences in outcomes secondaryto RSI.44

Hemodynamic and Fluid Management

In pregnant and nonpregnant patients alike, the goal is to maintain perfusion andoxygenation of vital organs. During pregnancy, vital organs also include the uterusand placenta. Much of the effect of medications on the fetus is not a direct effectbut is secondary to an effect on maternal physiology and subsequent uterine perfu-sion.45,46 The effect is further compounded because uterine circulation is not autore-gulated in the same manner as circulation to other vital organs. Thus, vasopressorsmay have little or no direct effect on uterine circulation. Physical maneuvers, suchas fluid bolus, Trendelenburg position, compression stockings, and leg elevation,may have larger impacts on increasing uterine blood flow.28

Mechanical Ventilation

Both hyperventilation and hypoventilation can have detrimental effects, so cliniciansmust be vigilant with pregnant women under general anesthesia. As discussed earlier,pregnancy is associated with a chronic respiratory alkalosis secondary to increasedalveolar ventilation. Higher levels of carbon dioxide in hypoventilation may lead toan increased gradient across the placenta and cause acidosis andmyocardial depres-sion of the fetus. In contrast, hyperventilation may lead to severe alkalosis andcompromise of fetal blood flow and oxygenation.47–50 Thus, mechanical ventilationduring anesthesia should maintain the normal physiologic respiratory alkalosis whenbreathing spontaneously rather than attempt to correct it to usual normal parameters.

SURGICAL APPROACH

Once a diagnosis is confirmed and the decision to operate is made, the surgicalapproach is based on the disorder, surgical skill, and the availability of equipmentand staff. When plausible, the benefits of laparoscopy in pregnancy seem to mimicthe benefits seen in nonpregnant patients, including decreased postoperative painand narcotic use, decreased rate of postoperative ileus, decreased length of hospitalstay, and quicker return to work.51–55

Laparoscopy

Initial port placementGiven the concern for possible uterine or fetal injury, laparoscopic abdominal accessin pregnant patients has been debated in the literature. Because the intra-abdominaldomain is significantly altered during the second and third trimesters, access via asubcostal approach has been advocated. If the site of initial access is adjusted basedon consideration of fundal height, the Hasson technique, Veress needle, and opticaltrocar all seem to provide safe entry options.37,41,56–58 Surgeons should assess their

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own comfort levels with these approaches and proceed with the safest meanspossible.

Carbon dioxide insufflationThe concern regarding carbon dioxide insufflation in pregnant patients stems from thepotential for respiratory compromise secondary to diaphragm displacement and thepossibility of peritoneal absorption of carbon dioxide. A pressure of 15 mm Hg is typi-cally used in nonpregnant patients and has been routinely used without increasingadverse maternal/fetal outcomes.3,41,56 With regard to carbon dioxide exchangeand possible fetal acidosis, no data exist showing detrimental effects to the fetus.4

As noted earlier, clinicians should consider monitoring in the situation of a viable fetus,and this may provide some guidance with regard to intraoperative effects.

Open Approach

If an open approach is chosen, the type of incision depends on the surgical procedureand gestational age. A vertical incision is used for ease of incisional extension ifneeded to facilitate exposure.

POSTOPERATIVE PAIN MANAGEMENT

Pain control in the postoperative period is also important. Nonsteroidal antiinflamma-tory drugs should not be used in pregnancy because of the risk for premature closureof the ductus arteriosis.28,59 Therefore, opioids, intravenous and oral, are the painmedications of choice. If intravenous opioids must be used, a patient-controlledanalgesia pumpmay be the best initial option, given its low associated risk of maternalrespiratory depression. As in all patients, intravenous pain medications should be con-verted to oral forms as soon as possible. It is recommended that patients be weanedoff all narcotics as soon as possible to avoid fetal dependence. Babies born withopioid dependency can manifest decreased birth weight, respiratory depression,and extreme drowsiness, which can lead to feeding problems.28 However, this consid-eration should not deter the surgeon from providing adequate perioperative pain con-trol for pregnant women.

OUTCOMES/SUMMARY

The goals of treating pregnant patients in the perioperative setting are the same aswith any patient: to provide safe preoperative, operative, and postoperative care.This task is complicated by the need to consider the well-being of both of the motherand the fetus. Moreover, the primary patient, the mother, has altered physiology. Sur-geons must be aware of the physiologic and anatomic changes of pregnancy andrecognize the surgical and anesthetic modifications necessary for safe care. Providerscan be encouraged that surgical outcomes in pregnant patients have been shown tobe similar to those of nonpregnant patients. A review article published in 2005 basedon studies from 1966 to 2001 (the largest available) reveals that the overall rate ofmiscarriage in pregnant women exposed to surgical intervention in the first trimesteris 10.5%, which is similar to the rate of miscarriage in the general obstetric population.Moreover, the overall rate of birth defects (approximately 2%) was not significantlyincreased compared with the general obstetric population. The aforementioned studyalso quantified the risk of delivery related to surgery (3.5%) and the risk of fetal loss(0.8%–2.5%).60 It is also important to note, as validated in a study of 720,000 patients,that specific types of anesthesia or surgical procedures were not associated withdifferent outcomes. The rates of stillbirths and congenital malformations were similar

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in pregnant women who underwent operations during pregnancy compared withpregnant women who did not. The only significant differences were increased ratesof low birth weight infants and early neonatal death, with relative risks of 2.0 and 2.1respectively. Even in these situations, it is difficult to determine whether these findingswere secondary to the procedures or to the disorders.2 In conclusion, surgicaldiseases arise in pregnant and nonpregnant patients alike. Delayed diagnosis andmanagement, secondary to avoidance of fetal risk of diagnostic or therapeuticinterventions, pose a greater risk to the mother and fetus than radiation, anesthesia,or operative intervention.

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