COVID-19 Updates for Pregnancy

Since our update in March, we now have much more data – so much in fact that it may be really hard for everyone to synthesize it all. Our hope is to help a little with the synthesis and present the information out there in a digestible way – obviously we won’t be totally comprehensive, but we’ll do our best!

Pregnancy and COVID-19 Risk

The CDC released a new morbidity and mortality weekly report (MMWR) in November 2020:

• Looked at data from 1/22-10/3/2020 with delay for data updates up to 10/28/2020 in both pregnant and nonpregnant symptomatic women between the ages of 15-44 (reproductive age).

  • 409,462 symptomatic women 

  • 23,434 (5.76%) symptomatic pregnant women 

• Suggestion: pregnant women are MORE likely to have severe COVID-19 associated illness. After adjusting for age, race, other med conditions, pregnancy women were: 

  • More likely to be admitted to the ICU (10.5 vs 3.9/1000 cases, ARR 3.0) 

  • More likely to receive ventilation (2.9 vs 1.1/1000, ARR 2.9) 

  • Receive ECMO (0.7 vs 0.3/1000, ARR 2.4) 

  • And die… (1.5 vs 1.2/1000, ARR 1.7) 

• Some other interesting findings: 

  • Older pregnant women were more likely to have ICU admission/severe disease, comparing women 35-44 with women 15-24 (19.4 vs 7.6/1000 cases) 

  • Black women had higher risk of death (made up of 14.1% of all women involved, but represented 36.6% of deaths overall, including 26.5% of pregnancy deaths) 

  • Increased risk of ICU admission for Asian women (ARR 6.6) and native Hawaiian/Pacific Island women (ARR 3.7) 

  • In pregnant Hispanic women, pregnancy was associated with 2.4x risk of death 

•     Some limitations: 

  • COVID-19 cases rely on voluntary report by health care providers and public health officials/agencies 

  • Reporting bias – we might report more if there is more severe disease (less likely to report asymptomatic or mild disease) 

  • Severe outcomes might require more time to ascertain (why they had time lag of 10/28 when looking at cases reported through 10/3/2020).

Smaller studies have been performed to assess other pregnancy outcomes. Studies may be too small to be powered for these differences, but are still being actively studied:

• Preterm labor/stillbirth 

  • Overall during the pandemic:

    • Danish report showed decreased preterm birth rates overall;

    • Another UK study showed increased rates of both;,

    • JAMA Dec 7, 2020 in Philadelphia did not show increased rate during the pandemic. But conflictingly, a study in the same city in October showed that there was a decreased PTB rate at one hospital 

    • Could hypothesize these varying outcomes may be due to different time periods, different lock-down methods, etc. 

• PEC/cesarean deliveries/PTB in people with COVID 

  • One study from Texas looked at 3374 women who were tested for COVID, of whom 252 were positive.

  • In positive women, there was no difference in composite outcome of PEC w/ SF, cesarean delivery, or PTB.

• Looking at PTB from the Birth and Neonatal Outcome MMRC from CDC: there was a preterm birth rate of 12.9% in women with COVID-19 infection, which was higher than general population in 2019 (10.2%), so maybe there is an increased risk for preterm delivery.

Birth and Neonatal Outcomes after COVID-19 

There has been concern about perinatal infection in women who are COVID-19 positive and laboring. Fortunately we’ve got some reassuring data on this front from the CDC:

• 5252 women with lab-confirmed COVID-19’s babies  610 (21.3%) of infants had reported COVID results

  • Perinatal infection – uncommon (16, 2.6%) and occurred primarily among infants whose mother had COVID ID’ed within 1 week of delivery.

  • 8 of the infants were born preterm (26-35 weeks) and admitted to NICU 

  • 8 term infants who were positive, one was admitted to NICU for fever and O2, the others were not admitted, and one did not have info.

COVID-19 Vaccination in Pregnant and Breastfeeding People  

When we recorded the episode, we spoke primarily about the Pfizer vaccine. This information should apply in broad strokes the the Moderna vaccine as well, now that it has received approval as the 2nd mRNA vaccine.

• mRNA vaccine – What is it, how does it work? 

  • mRNA: messenger RNA. It is single-stranded RNA molecule that is complementary to one of the DNA strands of a gene. Reaching back to med school: mRNA leaves the cell nucleus and moves to the cytoplasm where they code for different protein synthesis. Ribosome will move along the mRNA, read the base sequence, and use the genetic code to translate three-base triplet (codon) into its corresponding amino acid 

  • tRNA: which is attached to an amino acid, will match with mRNA to generate a sequence of amino acids to make up a protein 

• The COVID-19 mRNA vaccine gives instructions to our cells to create a “spike protein,” which is a harmless piece of protein that is found on the surface of the virus that causes COVID-19 

• Once the mRNA is used, the cell gets rid of the material… so you can’t get infected with COVID-19. It also doesn’t get encoded into our DNA!

  • Once your cell makes the protein, it presents it on the surface of the cell. The immune system will recognize that this protein doesn’t belong there and begin to build up an immune response and make antibodies, kind of like what would happen in the natural infection against COVID-19. 

  • At the end of the process, your immune system will recognize these surface proteins from COVID-19 and have the ability to fight them off, so if you come into contact with COVID-19, your immune system will be ready 

• How was it developed so fast? 

  • Most of the time, vaccine trials take a long time because there are hang-ups in things that have nothing to do with science: funding, IRBs approval, etc.

  • But because this was coronavirus, there was a lot of funding and momentum from Operation Warp Speed.

    • OWS is a partnership with the Department of Health and Human Services, CDC, NIH, Biomedical Advanced Research and Developmental Authority (BARDA), and Department of Defense 

    • Since March, the HHS has given a TON of money to vaccine research:  https://www.hhs.gov/coronavirus/explaining-operation-warp-speed/index.html#:~:text=August%2011%3A%20HHS%20announced%20up,the%20option%20to%20acquire%20more.

  • Pfizer received $1.95 billion in July for production of 100 million doses of vaccine, and Congress directed almost $10 billion to the overall effort of vaccine development/distribution. Most of the time, vaccine research does not get this much money all at once! 

• Is it safe?

  • For the Pfizer vaccine, the Phase 3 clinical trial began on July 27 and enrolled 43,661 participants, and 41,135 received a second dose

  • The trial concluded 11/13/2020, so there is at least 3.5 months’ worth of data. We don’t really expect long term outcomes to be different… since mRNA gets destroyed by the body so quickly.

  • Findings: 

    • Looking at 28 days after first dose of vaccine (remember, we need time for the vaccine to work), there were 170 confirmed cases of COVID-19: 162 in the placebo group vs. 8 in the vaccine group.

    • Efficacy was consistent across age, gender, race, and ethnicity demographics.

    • Efficacy was 95% overall, and 94% in adults >65 years of age.

    • Safety in general: well tolerated across all populations, no serious safety concerns observed. The only Grade 3 adverse event >2% in frequency was fatigue (3.8%) and headache (2.0%). Older adults tended to report fewer and milder solicited adverse effects following vaccination 

  •  What about reports of the 6 people that died in the Pfizer Phase III trial? 

    • 6 people did die in the trial. 4 were in the placebo arm, and 2 were in the actual vaccine arm.

      • Of the two that died: 1 was reported to have serious adverse event related to arteriosclerosis and died 3 days after dose 1; the other had a cardiac arrest 60 days after dose 2 and died 3 days later. Both were > 55 years of age. 

      • Of the 4 that died in placebo arm: 1 died 8 days after dose 1 with unknown event, one died of hemorrhagic stroke 15 days after dose 2, one died 34 days after dose 2 (unknown event), one died of MI 16 days after dose 1. 

  • Other serious adverse events 

    • The non-fatal SAE was 0.6% in the vaccine group and 0.% in the placebo group 

    • Vaccine group had higher rates of appendicitis (0.04%), acute MI (0.02%), and CVA (0.02%)

    • Placebo arm had higher rates of pneumonia (0.03%), afib (0.02%), and syncope (0.02%) 

  • Editorializing here: but the overall small numbers, the variety of things that occurred, and the lack of biologic plausibility in these SAEs suggest these likely happened by chance.

• Should pregnant and breastfeeding people get vaccinated? 

  • Unfortunately, pregnant and breastfeeding people were excluded from the study 

  • Currently, the FDA has not excluded pregnant and breastfeeding people from getting the vaccine 

  • SMFM is in agreement – recommend that pregnant and lactating people have access to the vaccine 

  • Can engage in discussion about potential benefits and unknown risks with their providers 

Peripartum Cardiomyopathy

What is Peripartum Cardiomyopathy? 

• Definitions:

  • Potentially life-threatening pregnancy-associated disease that typically arises in the peripartum period and is marked by left ventricular dysfunction and heart failure - from Arany Z, Elkayan U. Peripartum Cardiomyopathy in Circulation from April 2016.

    • It’s not a precisely defined entity, because timing can vary. 

  • The US National Heart, Lung, and Blood Institute (NHLBI) in the 1990s defined PPCM as heart failure that develops in the last month of pregnancy or up to 5 months postpartum

    • This excludes patients that have pre-existing cardiomyopathies, but there are patients who otherwise meet criteria for PPCM who are <36 weeks.

  • Many definitions require cardiomyopathy to demonstrate reduced LV systolic function, where LVEF < 45%, fractional shortening <30%, or both.

• Epidemiology:

  • Ranges from 1/1000 to 1/4000 live births, but potentially increasing.

  • Proposed reasons: 

    • Increasing maternal age, preeclampsia, and multiple gestations, which are all risk factors for PPCM.

    • Also increasing HTN, diabetes, and obesity.

    • Also just growing recognition of PPCM as a disease entity.

• Symptoms/Signs:

  • Usual symptoms of heart failure:

    • Ie. fatigue, shortness of breath, increased extremity swelling, sometimes arrhythmias from overstretching of the heart.

  • Signs on exam:

    • Evidence of left sided congestion (pulmonary rales), right side congestion (ie. increased JVP and edema) 

    • Elevated BNP (Malhame in Green Journal 2019) 

    • EKG may show non-specific changes like LBBB pattern

    • Chest Xray: may show pulmonary edema and enlarged cardiac silhouette 

    • Echo: LV dilation of variable degrees, LV systolic dysfunction, RV and bi-atrial enlargement; LVEF < 45%  

What causes PPCM? 

• Older hypothesis: triggered by viral myocarditis 

  • However, a study that looked at endomyocardial biopsies in patients with PPCM and other types of cardiomyopathies, the same proportion of specimens in each group had detectable viral genomes (30%).

• Current hypothesis: “two hit” model 

  • Vascular insult - due to antivascular or hormonal effects of late pregnancy and early postpartum period → cardiomyopathy in women with an underlying predisposition.

  • There is also question of genetic predisposition 

  • High prevalence of pre-eclampsia in women with PPCM suggests a possible shared pathophysiology - perhaps some type of placental angiogenic factor.

How do we manage PPCM? 

• Prognosis: 

  • 50-80% of women with PPCM recover to normal range LVEF (>50%) with most recovery occurring within the first 6 months.

    • This is pretty good considering that in the early 1970s, the mortality of PPCM was 30-50%.

  • LV size and EF at time of diagnosis most strongly predict LV recovery.

    • LVEF <30% and LV end-diastolic diameter > 6 cm are indicative of decreased likelihood of left ventricular recovery and increased risk of mechanical support, transplant, and death.

  • 25% of patients will develop chronic heart failure, and mortality rate is still 6-10% in the United States (depending on follow up defined for mortality rate by study).

• Complications

  • One study found that 2.6% of women with PPCM in the US had cardiogenic shock, 1.5% of them needed mechanical circulatory support, and 0.5% of women underwent cardiac transplantation.

  • VTE is one of the most common severe complications of PPCM - affect 6.6% of women.

    • Mechanism: underlying intracardiac thrombosis in PPCM d/t cardiac dilatation and hypocontractility → blood stasis.

    • Also pregnancy is a hypercoagulable state.

  • Arrhythmias - can contribute to morbidity and mortality d/t death from VTach.

    • 2.1% of women with PPCM had cardiac arrest and 2.9% underwent implantation of a cardiac device.

• Treatment 

  • Few studies performed specifically in women with PPCM, so management strategies are generally extrapolated from other forms of heart failure.

  • Multidisciplinary care: MFM, anesthesia, and cardiology.

  • Individualized discussion of delivery timing for optimal maternal-neonatal outcome.

  • Usually don’t need to do a cesarean.

    • Hemodynamic shifts may be mitigated by slow epidural and assisted second stage of labor.

  • Care overall is usually supportive, directed toward managing heart failure symptoms.

    • Diuresis (but don’t go overboard and cause hypotension) 

    • If hemodynamics permit, beta blockers should be used, with preference of B1 selective ones (ie. metoprolol).

      • B2 blockers may prompt uterine activity, so better to avoid.

    • ACE-inhibitors and ARBs are considered contraindicated in pregnancy, but can use them postpartum.

    • Consider anticoagulation in PPCM if LVEF < 30% 

    • If arrhythmias, may require acute or chronic administration of antiarrythmic drugs.

  • Cardiac assisted devices - may be indicated if severe depression of LV function or if concerned for rapid deterioration.

• After PPCM, future pregnancy: 

  • Avoid future pregnancy if EF fails to improve, as mortality increases up to 50% if EF does not improve!

Cervical Cancer

Today we welcome Erin Lips, MD to the podcast. She’s a current 2nd year GYN Oncology fellow at Brown University / Women and Infants of RI!

Cervical cancer is almost a completely preventable disease, yet it represents the 4th most common female malignancy worldwide. The burden of cancer and cancer-related deaths is disproportionately weighted toward populations without access to adequate screening or adequate treatments: 

• 90% of cancer deaths occur in low and middle income countries:

  • Mortality in these countries is 18x higher than in developed countries.

  • In 2012, in high income countries, cervical CA was 11th most common female cancer and 9th most common cause of cancer mortality 

  • In LMICs by comparison, it was the 2nd most common cancer and the 3rd most common cause of cancer death.

  • In Africa and Latin America, cervical cancer is the leading cause of cancer specific mortality in women. 

• SEER estimates 13,800 new cases in the US for the year 2020 and 4290 deaths. 

  • In the US, median age of diagnosis is 47-50 years, and half are diagnosed under 35. 

  • Within the US, racial, socioeconomic, and geographic disparities exist in cervical cancer.

    • Black and Hispanic patients have the highest rates.

    • There is also geographic differences in incidence between states.

    • Multifactorial, but overall due to poor access and barriers to routine care.  

• In high income countries, incidence and mortality have decreased by more than half over last 30 years due to formalized screening programs, involving Pap and HPV testing.

Cervical Cancer Risk Factors:

• Chronic high risk HPV infection causes almost all cases of cervical cancer!

• Early age of sexual debut

• Higher number of sexual partners or high risk sexual partner

• Immunosuppression (organ transplant or HIV)

• h/o STIs

• h/o HPV-related vulvar or vaginal dysplasia

• Non-attendance for screening

• Tobacco is a major risk factor, doubling risk of dysplasia and cancer even after adjusting for HPV status. 

  • Smoking cessation associated with 2-fold risk reduction!

Primary Prevention: the HPV vaccine

• 90% efficacy in preventing HPV 16 and 18 (the 2 types most highly associated with high grade dysplasia). In 2018. a nine-valent vaccine was introduced that covered additional high-risk serotypes.

• Australia was the first country to establish an HPV vaccine program in 2007

  • >70% vaccine coverage in boys and girls aged 12-13 yrs. 

  • 38% reduction in high grade dysplasia in young women within 3 years!

• In countries where at least 50% of females are vaccinated, HPV 16 and 18 infections decreased by almost 70%.

  • In the USA, HPV coverage by 2014 was <50% in girls under age 17

Secondary Prevention: Papanicolau smear 

• Primary HPV testing will likely take over, but we are still holding on to our cotesting strategy and most institutions can’t let go of cytology yet!

• Check out the Pap smear episode for more: Episode 1; Episode 2

Clinical presentation:

• Early stages: 

  • Often asymptomatic 

  • Post-coital or abnormal vaginal bleeding, malodorous discharge

  • Diagnosed after routine screening or pelvic exam

• Advanced disease: limb edema, flank pain, sciatica

• Fistula: passage of urine or stool through the vagina suggests invasion into bladder or rectum c/w vesicovaginal or rectovaginal fistula 

Diagnosis:

• Based on histopathological assessment of a cervical biopsy

  • 80% Squamous, 20% Adenocarcinoma

• Usually when cervical cancer is diagnosed in the US, next step is to stage:

  • A cold-knife cone excisional procedure will often be performed first - with smaller tumors, this is to ensure disease is not more advanced. This may be the point of first diagnosis after identifying dysplasia on Pap/colposcopy.

  • If cancer is diagnosed, in the US:

    • PET/CT scan

    • proceed to the OR for an exam under anesthesia (EUA), cystoscopy, and proctoscopy. 

    • Assess for parametrial invasion on EUA. 

    • Depending on the stage and plan, patient may or may not warrant lymph node dissection. Radiation oncology could be consulted to examine as well for radiation planning.

Staging:

This is a popular topic to be tested on CREOGs and board exams! However, it’s important to know that there is a new FIGO staging system we are now using.

• Traditionally, staged clinically based on exam and use of limited imaging because this cancer is so prevalent in LMICs, and PET scan or surgical staging is not always accessible in these areas. 

  • For instance: in the old staging system, you would choose the stage based on exam. If the patient then ended up having pathologically proven lymph nodes, you might still say “this is a stage IB with positive para-aortic lymph nodes” instead of upstaging to at stage III (like you do in endometrial cancer).

• In 2018, FIGO introduced a new staging system which does incorporate radiologic and lymph node positivity into the staging system, and now resembles endometrial cancer staging that way. You can see them side-by-side below:

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FIGO 2018 Staging

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FIGO 2009 Staging

First Line therapies 

• Rule of thumb is that the ideal approach to these patients is to have the intention of doing either curative surgery or curative radiation, but not both. 

• Surgery and radiation are equally effective but morbidity of doing both is significant and increases risk for lifelong complications. SInce these patients are often young and many have young children, this is a very important piece to consider.

SURGERY:

• Cutoff for surgical candidacy is early. 

• Candidates are patients with a small tumor confined to the cervix (<4cm in size), with no spread to parametria, lymph nodes, or anything else. 

  • IA1 and no lymphovascular space invasion (LVSI): simple hysterectomy, 

  • IA1 with LVSI and IA2: Radical hysterectomy, pelvic lymph nodes

  • IB1, IB2, IIA1 (i.e., tumor <4cm or confined to upper vagina with no parametrial involvement): Radical hysterectomy, pelvic lymph nodes

  • IB3 (AKA tumor >4cm) and beyond: Chemosensitizing radiation. 

  • Distant metastases: Just chemotherapy (no radiation).

• During surgery, if any lymph nodes are enlarged, those should be removed and sent immediately to path → if positive, abort the hysterectomy, sample PALN, and plan for chemoradiation instead.

• After hysterectomy, assess for SEDLIS or PETERS criteria to determine whether patient needs post-op radiation

  • SEDLIS: HIR criteria (tumor size, depth of invasion, and LVSI)

  • PETERS: High risk criteria (positive margins, parametria, or lymph nodes)

What to do about ovaries?

• Usually leave in situ unless patient is post-menopausal

  • Risk of mets to ovaries is very low, and you’re usually only doing surgery if you think it’s very early stage anyway. 

LACC trial 2018: 

• Widely disseminated change of “standard of care” to abdominal rad hyst (not MIS)

• Large Phase III randomized clinical trial comparing outcomes of MIS vs open radical hysterectomy.

• Trial terminated early due to higher recurrence rates and more deaths in the MIS group

  • At 4.5 years, 96.5% of pts who had open surgery had no recurrences, but only 86.0% who had MIS had no recurrences 

  • At 3 years: 99.0% of pts who had open surgery were still alive, while only 93.8% who had MIS were still alive (HR 6.0)

Fertility Sparing Surgical Options:

• IA1 no LVSI: Cone with neg margins

• IA1 with LVSI, IA2: Cone and LND OR Radical trachelectomy and LND

• IB1, select IB2: Radical trachelectomy and LND (traditional cutoff is <2cm tumor size for trachelectomy)

RADIATION:

• If pre-operatively it is known the patient is not a candidate for surgery, want to keep the uterus and cervix in situ to allow for the optimal radiation treatment to be administered.

• PET/CT will usually help delineate spread to lymph nodes. However, if no PALNs lit up, can go to OR to sample. This helps with mapping of RT fields.

• Standard RT is co-administered with chemotherapy, which we call “chemoradiation” or “chemosensitizing radiation.” 

  • Weekly small doses of Cisplatin during course of RT, 5-6 cycles

  • RT is combination of EBRT (whole pelvic) and internal brachytherapy

    • EBRT is 45Gy, divided into 25 fractions. 

      • This means daily, 5 days a week, for 5 weeks

    • Brachytherapy is another 40 Gy, divided up into fractions. 

      • administered via one of several methods: tandem and ovoids, tandem and ring, tandem and sleeve, etc. 

      • LDR (Low dose rate) vs HDR (high dose rate)

      • Interstitial - for cases of obliterated anatomy- radiation source loaded into needles, which are placed into the tumor and remain in place for prescribed period of time for treatment.

  • Very important to stay on schedule, as timing of RT is crucial for optimal cell kill and efficacy. 

CHEMO for METASTATIC DISEASE:

• Typically Cisplatin/Paclitaxel/Bevacizumab

Cervical cancer in pregnancy: 

• Though breast cancer is most common cancer diagnosed in pregnancy, cervix is the most common GYN malignancy in pregnancy - might actually diagnose earlier because of increased care, so usually stage I.

• If gestation is still pre-viable and the patient desires termination, then usually a gravid hysterectomy or radical hysterectomy and lymph node dissection is performed.

• If >24 weeks or if the patient desires continuation of pregnancy, then patient has the option for neoadjuvant chemotherapy until delivery. Deliver via C-section and then can perform a cesarean radical hysterectomy if appropriate mode of treatment OR postpartum RT if non-operative management is indicated.

  • Vaginal delivery is contraindicated in known diagnosis of cervical cancer!

Pelvimetry

What is pelvimetry? 

• Measurement of the female pelvis that has theoretically been used to try and identify cephalo-pelvic disproportion.

• Originally described by Dr. Caldwell and Dr. Moloy in “Anatomical Variations in the Female Pelvis: Their classification and Obstetrical Significance” in 1938.

• Clinical evidence shows, however, that all pregnant women should be allowed a trial of labor regardless of pelvimetry results!

  • Cochrane review in 2017 that looked at deciding mode of delivery for cephalic fetuses at term:

    • X-ray pelvimetry vs. no pelvimetry or clinical pelvimetry was the only comparison used due to lack of trials identified that used other types of pelvimetry.

    • There was not enough evidence to support use of X-ray pelvimetry for deciding mode of delivery.

    • Women who underwent X-ray pelvimetry were more likely to have C-section, but there was no clear difference in perinatal outcomes in these groups.

  • Even the WHO in Feb 2018 stated that routine clinical pelvimetry may increase cesarean section without clear benefit for birth outcomes

• Ok… so why are we even talking about pelvimetry? 

  • Historical purposes so that you know what people are talking about.

    • CREOGs sometimes test on the different measurements of the pelvis used! 

What are the traditional types of pelvises? 

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• Gynecoid - round to slightly oval inlet 

  • Traditionally the pelvis that is most likely in women; most “favorable” for SVD.

• Android - triangular inlet, and prominent ischial spines, with more angulated pubic arch

  • Thought to lead to longer labor or cephalo-pelvic disproportion.

• Anthropoid - the widest transverse diameter is less than the anteroposterior (obstetrical) diameter.

  • Traditionally thought to lead to more OP babies 

• Platypelloid - Flat inlet with shortened obstetrical diameter. Wide or transverse oval appearance “kidney shaped.” 

  • Traditionally thought to be difficult for vaginal birth 

But remember! Clinical evidence shows that a trial of vaginal birth should be done for all women regardless of pelvimetry

What are the various measurements for pelvimetry?

Pelvic Inlet 

• Transverse diameter of the pelvic inlet 

  • Measure the distance between the iliopectineal lines at the widest transverse distance (usually 13-14.5cm).

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• Obstetric conjugate 

  • Line between the closes bony points of the sacral promontory and the pubic bone next to the symphysis (normally 10-12 cm).

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• Interspinous distance 

  • The line between the closest bone points of the ischial spines (9.5-11.5cm) 

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Pelvic outlet 

• Sagittal pelvic outlet diameter aka obstetric AP diameter of the pelvic outlet 

  • Closest bony points of the sacrococcygeal joint and the pubic bone next to the symphysis (normally 9.5-11.5cm) 

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• Intertuberous diameter 

  • Closest bony points of the ischial tuberosities (normally 10-12 cm)

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The Surgical Abdomen in Pregnancy

A “surgical” or “acute abdomen” is a serious acute intra-abdominal condition accompanied by pain, tenderness, and muscular rigidity, for which emergency surgery should be contemplated.

This can be complicated by pregnancy because there are many physiologic and anatomic changes in pregnancy that can sometimes change the presentation of what we usually associate with acute abdomen 

Anatomic and physiologic changes in pregnancy

• Enlarging uterus 

  1. Uterus becomes intra-abdominal organ instead of pelvic organ at 12 weeks.

  2. Can increase from 70g → 1110g and hold up to 5 L volume.

  3. Uterus can compress ureters → can look like hydronephrosis and mimic urolithiasis.

  4. Will displace other abdominal organs (mostly the viscera):

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Zachariah SK et al. Management of acute abdomen in pregnancy: current perspectives. Int J. Womens Health. 2019;11:119-134.

•  A relaxed and stretched abdominal wall can mask guarding.

• Additional physiologic changes: 

  • GI: 

    • Delayed emptying of stomach, relaxed lower esophageal sphincter (remember: blame progesterone for everything!) → increase nausea/vomiting, bloating, GERD

    • Also decreased GI transit (slower motility d/t relaxed GI smooth muscles, again d/t progesterone) → Constipation 

      • Nausea and/or constipation with associated symptoms can confound clinical gestalt when evaluating acute abdomen.

  • Heme:

    • Leukocytosis -standard in pregnancy, though can give impression of infection.  

Recognizing the Acute Abdomen in Pregnancy 

• If someone comes with acute abdomen signs, you should treat them as if they have an acute abdomen until proven otherwise:

  • Abdominal rigidity, rebound, tenderness, guarding 

• Causes of acute abdomen in pregnancy:

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Some clinical pearls for more common causes of acute abdomen in pregnancy: 

• Appendicitis: Classically taught that the appendix is displaced in pregnancy, BUT RLQ pain is still the most common symptom. Fever might be present in some patients.

  • Ultrasound has sensitivity of 67-100% and specificity of 83-96% in pregnancy (first line imaging).

  • CT has sensitivity of 86% and specificity of 97% - usually not used as much due to concerns for radiation.

  • MRI has high sensitivity and specificity - generally 2nd line, if if ultrasound is inconclusive.

  • Treatment: SURGERY! 

• Cholecystitis: Murphy’s sign is still typically positive.

  • Ultrasound is the investigation of choice with sensitivity >95%.

  • Treatment: 

    • Admission, make NPO, give antibiotics.

    • Symptoms of cholecystitis may abate within 7-10 days of starting nonoperative treatment, but there is high risk of recurrence or serious complication.

    • In first and second trimester → good surgical candidates should undergo cholecystectomy.

    • In third trimester Nonoperative medical management with abx and fluid therapy should be tried first to allow delay of choley until postpartum, owing to technical difficulty in performing at this gestational age.

    • Remember, this is ONLY if it’s uncomplicated. If there is any sign of sepsis, perforation, or disease progression on antibiotics → immediate surgery.

A Word on Imaging 

• Recall our prior episode on imaging in pregnancy! The quick version:

• Try ultrasound first for acute abdomen. Usually has high sensitivity and specificity, but the efficacy can decline after 32 weeks of gestation because of technical difficulties due to enlarging uterus 

• Next is MRI, generally.

• For ionizing radiation:

  • Risk of radiation exposure on a developing fetus depends on both the dose of radiation and gestational age at which exposure occurs.

  • Fetal mortality is most significant in the first 2 weeks of conception (3-4 weeks pregnant).

  • Most vulnerable period for teratogenicity is during organ development (usually up to 12 weeks).

  • Risk of ionizing radiation-induced fetal harm is negligible at 50 mGy or less and risk of malformation increases only slightly with doses >150mGy.

    • Usual dose of CT abdomen/pelvis is about 25 mGy, and can be reduced to 13 mGy with automated exposure control facility in modern CT scanners.

A Word on Mode of Surgery 

• We are not general surgeons! 

• However, multiple studies show that laparoscopic surgery is less invasive and is feasible and safe in select pregnant patients.

• If you can time surgery, the best time is 2nd trimester or very early 3rd tri 

  • Pregnancy itself does not increase postoperative morbidity in pregnant women compared to nonpregnant women.

  • Timing works due to decreased exposure of fetus to anesthetic agents during organogenesis and decreased risk of SAB compared to 1st trimester.

  • In second trimester, uterus is not so big that it is hard to work around.

• Obstetricians should be able to counsel/provide for intraoperative or peri-operative fetal monitoring if indicated and feasible — generally pre/post doptones pre-viability, and a discussion about continuous monitoring if after viability.

• Postoperative care considerations:

  • If viable fetus, there should be additional monitoring of fetal heart rate and uterine activity post operatively.

  • If not viable, there should be dop tones obtained both before and after surgery 

  • For post-op pain, usual post-op care is usually permissible.

    • Avoid NSAIDs if possible after 32 weeks due to concern for premature closure of the fetal ductus arteriosis.