Key content
 Appendicitis in pregnancy is common.
 Whether to deliver a pregnant woman with appendicitis is a
contentious issue.
 There are many uncertainties with diagnosis of appendicitis
in pregnancy.
 Management of pregnant women with appendicitis requires a
multidisciplinary approach involving obstetricians, anaesthetists
and surgeons.
Learning objectives
 To understand the modalities useful in accurate diagnosis of
appendicitis in pregnancy.
 To learn about the range of clinical presentations and
differential diagnoses.
 To appreciate the risks involved with different management
options, anaesthetic and surgical.
 To be able to manage a pregnant woman with suspected
appendicitis for the best possible outcome.
Ethical issues
 Operative delivery of a pregnant woman with appendicitis may put
her at unnecessary risk. How should she best be managed for the
best possible outcome for her and the fetus?
Keywords: appendicitis / delivery / pregnancy / risk / surgery

Introduction
A pregnant patient presenting with suspected appendicitis
presents an interesting clinical question to both obstetricians
and general surgeons (Box 1). It is not clear whether acute
appendicitis is an indication for delivery of a term infant or
whether entry into the uterus is best avoided in the case of
intra-abdominal sepsis. Certainly the appendicectomy may
be easier to perform once the uterus is empty but in a young
primiparous patient is this sufficient indication for
undertaking caesarean section (CS)? And in cases where the
fetus is premature, how should the patient best be managed?
A review was undertaken to clarify management for such
cases in future.
Background
Acute appendicitis is inflammation of the appendix, which in
its worst form can lead to rupture. It is the most common
cause of an acute surgical abdomen in pregnancy. Despite
this, results from the Swedish registry study which compared
778 patients undergoing appendicectomy in pregnancy with
non pregnant population based age matched controls found
that the pregnant women were, in fact, less likely to develop
appendicitis (odds ratio 78, 95% CI 0.73–0.82).1
In developed countries acute appendicitis is suspected in 1/
800 pregnancies and confirmed in 1/800 to 1/1500.2 Its
incidence is most common in the second trimester.2
Symptoms and signs
Patients with appendicitis in pregnancy often present in a non
classical way (Table 1). In the classic presentation, central
abdominal pain localises to the right iliac fossa – at McBurney’s
point which is 6 cmalong a line from the anterior superior iliac
spine toward the umbilicus.3 Pain is associated with anorexia,
nausea and fever up to 39.3°C with raised white cell count.
Underlying inflammation irritates the anterior abdominal wall
causing signs of rebound and guarding; the ‘surgical’ abdomen.
Rovsing’s sign of increased pain on withdrawing the examining
hand from the abdomen demonstrates peritoneal irritation.
A pregnant patient may present with heartburn,
constipation, diarrhoea, urinary symptoms or just general
malaise. Pain may be felt in McBurney’s point or anywhere on
the right side of the abdomen.4 This occurs because after 12 weeks the enlarged uterus stretches the anterior abdominal
wall and omentum away from the area of inflammation. This
prevents the classic signs of rebound tenderness or guarding

 

Case study
SA, aged 22 years, presented to the emergency department in her first pregnancy at 37 + 6 weeks of gestation. She gave a 4-day history of right sided
abdominal pain and feeling generally unwell. She had some nausea but no vomiting, bowel or urinary symptoms. On examination she was
normotensive at 100/50 mmHg, with a pulse of 80 beats per minute and a temperature of 38.1°C. Her abdomen was soft, with a gravid uterus
appropriate for dates and right iliac fossa tenderness with localised guarding but no rebound. Urinalysis was negative. Blood analysis showed a
C-reactive protein of 20 mg/L, white cell count of 12x109/L with a neutrophilia, normal liver function tests. She was thought to have appendicitis, was
commenced on intravenous amoxicillin and metronidazole and transferred to the nearest obstetric unit with surgical cover. She was given appropriate
analgesia. Cardiotocography (CTG) was normal.
On arrival she was reviewed by the general surgeons on call who felt she was likely to be suffering from acute appendicitis. She was booked for
surgery the following morning. The plan from the surgical registrar was that she should have a caesarean section (CS) prior to the appendicectomy so
that the same incision could then be used. This was outlined to the patient and her family.
Later that evening she was reviewed by the obstetric team. It was felt that there was no indication for caesarean section. The plan was changed so
that the surgery should start with appendicectomy. If the appendix appeared infected then the uterus would be left intact, baby undelivered. If the
appendix appeared normal then a CS would be considered. The rationale was that if there was appendicitis it would be better not to open the uterus for
risk of introducing infection with possible deleterious effects on future fertility. Instead the patient could recover from the surgery, await spontaneous
labour and ideally achieve a normal delivery weeks later.
If there was no appendicitis found, other intra-abdominal sources of sepsis would have to be excluded. If chorioamnionitis was thus diagnosed by
exclusion, then CS might be advisable. In that scenario a CS would be safer since there would be no intra-abdominal infection present.
The patient and family were extremely distressed to learn that they would not necessarily be getting their baby delivered that day. They demanded to
have a CS at the same time as the appendicectomy. The reasoning was repeated a number of times and eventually the patient agreed.
The patient underwent appendicectomy under spinal anaesthetic. A Lanz incision was made over the point of maximal tenderness. A swollen,
discoloured retroileal appendix was identified and excised, the stump ligated with 2.0 polyglactin (Vicryl, Ethicon Inc. Somerville, NJ, USA) and the
abdomen closed in layers. As the appendix was clearly inflamed a CS was not performed. The patient and her family were debriefed that she should now
make a full recovery. CTGs were performed postoperatively and were normal. SA went home on the second postoperative day. She was seen in
antenatal clinic weekly until she went into spontaneous labour at term plus 8. Labour was uneventful and she delivered a live male infant by
vacuum-assisted delivery under epidural anaesthesia. She was discharged home with her baby 3 days later and was extremely happy with the outcome.

Appendicitis in pregnant and nonpregnant patients5,21
Symptom/sign
Seen in
pregnancy
Seen in
nonpregnant
Right lower quadrant pain 75% 95%
Right upper quadrant pain 20% 5%
Nausea 85% 90%
Vomiting 70% 70%
Anorexia 65% 90%
Dysuria 8% 2%
Rebound tenderness 80% 90%
Abdominal guarding 50% 90%
Rectal tenderness 45% 45%
Low grade fever 20% 60%

Investigations
Investigations can be misleading in pregnancy. Nonpregnant
patients with acute appendicitis usually have a mild
leucocytosis, with white cell count over 10x109/L. This is a
common finding in normal pregnancy however, where the
leucocyte count may reach 29 x109/L without any underlying
health problem. In pregnancy an elevated white cell count
can be attributed to inflammation if the C reactive protein
(CRP) level is also raised. In general however, elevated CRP is
a very non-specific marker for inflammation.6
Imaging is indicated where the diagnosis is uncertain. The
primary goal of imaging is to reduce delays in surgical
intervention. The secondary goal is to reduce the negative
appendicectomy rate.7
Ultrasound may identify an enlarged appendix (a noncompressible,
blind-ending tubular structure in the right iliac
fossa exceeding 6 mm diameter), ovarian cyst or cyst
accident, fibroid or gallbladder disease. Sensitivity for
ultrasound in the diagnosis of appendicitis in pregnancy is
67–100% with specificity of 83–96%, the variability being due
to issues like gestational age, body mass index and
ultrasonographer error.8
Cardiotocography (CT) scanning for appendicitis in
pregnancy has a sensitivity of 86% and specificity of 97%.
The disadvantage of CT is the exposure of the mother and
fetus to radiation and its potentially carcinogenic effects. It
has not been clear during studies whether CT for appendicitis
is useful after an inconclusive ultrasound study.9
Magnetic resonance imaging (MRI) is an alternative
imaging technique for exclusion of acute appendicitis in
pregnancy when clinical examination and ultrasound are
inconclusive. Its appeal is the avoidance of exposure to
radiation. Evaluation of MRI in pregnant women with
suspected appendicitis confers a sensitivity of 91% and a
specificity of 98%.10 The American College of Radiology
dictates that MRI should be used in cases where ultrasound is
inconclusive for appendicitis in pregnancy.

Management
The treatment for acute appendicitis is surgery.14 The
decision to proceed to surgery in a pregnant woman should
be based upon clinical history, examination and imaging
results. If the diagnosis is certain, the decision to perform
appendicectomy is easy. Maternal morbidity following
straightforward appendicectomy is low, and equates to that
in the non pregnant population. The difficulty comes when
the diagnosis is unclear.
Maternal and fetal morbidity increase dramatically and
directly in relation to the severity of the appendicitis. Fetal
loss in simple appendicitis is 1.5%,15 with generalised
peritonitis 6%, and if the appendix perforates as high as
36%.16 Perforation of an infected appendix can cause
widespread pus and faecal soiling of the intra-abdominal
cavity. This can cause severe sepsis and a critically ill patient.
In addition to the risk of fetal loss, a perforated appendix
increases the risk of preterm delivery17 and future difficulties
with pelvic adhesions and subfertility.
Given the significant risks if the appendix perforates, a
lower index of suspicion is used for surgical treatment of
appendicitis in the pregnant patient and delay in definitive
management should be avoided. A higher negative
laparotomy rate is considered acceptable. Up to 35% of
laparotomies may be negative.18 This can reduced a little by
further preoperative imaging but is affected by relative
reluctance to undertake CT. If surgery does reveal a normal
looking appendix it should still be excised. Acute
inflammation of the appendix may be a purely histological
diagnosis, removal avoids future intervention, and the
surgery itself is low risk for complications.
The technique used for appendicectomy in a pregnant
patient depends on gestation, how sick the individual is and
available surgical expertise. If a perforated appendix is
suspected the patient should undergo immediate
laparotomy, appendicectomy and extensive irrigation of the
abdomen. If the patient is critically ill, delivery of the baby
(thus emptying the uterus) permits more effective maternal
resuscitation and faster recovery. Maternal welfare should
always be the priority and put ahead of the fetus regardless
of gestation.
Appendicectomy is best performed in any pregnant patient
through a transverse incision over the point of maximal tenderness. If the diagnosis is not certain, the general surgical
approach would be to make a low midline vertical incision on
the abdomen to allow exposure for surgical treatment of
appendicitis or any condition mimicking it.16,17 If CS was
necessary in due course, this same incision could be used
but extended.
Laparoscopic appendicectomy is gaining in popularity as a
technique. Case reports and small studies suggest that this is
safe and straightforward in all trimesters.17 A systematic
retrospective review and meta-analysis of observational
studies demonstrated an increased risk of fetal loss (relative
risk 1.91, 95% CI 1.31–2.77) for laparoscopic versus
open appendicectomy.19
Antibiotics should not be used alone in management
without surgery as they are not sufficient for
definitive treatment.20
There is minimal evidence for the management of ‘chronic
appendicitis’ in pregnancy.21 This is where the appendix has
ruptured but walled itself off thus limiting infection and no
longer requiring operative management. In nonpregnant
patients, a ‘walled off’ appendix may present with a relatively
well patient but a prolonged course of symptoms, palpable
right iliac fossa mass, and abcess seen on ultrasound.
Treatment consists of antibiotics, intravenous fluids and
monitoring. The patient may recover more quickly with such
conservative management rather than a surgical approach.
There are virtually no data about how to manage this
condition when pregnant. If the woman is well enough it
seems reasonable to delay definitive management until
after delivery.

Conclusion
Appendicitis in pregnancy is common. Fetal and maternal
outcomes are directly linked to the severity of inflammation.
Surgical management in pregnancy is the only option for cure
at any gestation. It seems that simultaneous delivery is only
indicated in cases of critical fetal or maternal compromise