Molecular diagnostics and therapeutics for ectopic pregnancy

Diagnostic utility of clinicodemographic, biochemical and metabolite variables to identify viable pregnancies in a symptomatic cohort during early gestation

A significant number of pregnancies are lost in the first trimester and 1-2% are ectopic pregnancies (EPs). Early pregnancy loss in general can cause significant morbidity with bleeding or infection, while EPs are the leading cause of maternal mortality in the first trimester. Symptoms of pregnancy loss and EP are very similar (including pain and bleeding); however, these symptoms are also common in live normally sited pregnancies (LNSP). To date, no biomarkers have been identified to differentiate LNSP from pregnancies that will not progress beyond early gestation (non-viable or EPs), defined together as combined adverse outcomes (CAO). In this study, we present a novel machine learning pipeline to create prediction models that identify a composite biomarker to differentiate LNSP from CAO in symptomatic women. This prospective cohort study included 370 participants. A single blood sample was prospectively collected from participants on first emergency presentation prior to final clinical diagnosis of pregnancy outcome: LNSP, miscarriage, pregnancy of unknown location (PUL) or tubal EP (tEP). Miscarriage, PUL and tEP were grouped together into a CAO group. Human chorionic gonadotrophin β (β-hCG) and progesterone concentrations were measured in plasma. Serum samples were subjected to untargeted metabolomic profiling. The cohort was randomly split into train and validation data sets, with the train data set subjected to variable selection. Nine metabolite signals were identified as key discriminators of LNSP versus CAO. Random forest models were constructed using stable metabolite signals alone, or in combination with plasma hormone concentrations and demographic data. When comparing LNSP with CAO, a model with stable metabolite signals only demonstrated a modest predictive accuracy (0.68), which was comparable to a model of β-hCG and progesterone (0.71). The best model for LNSP prediction comprised stable metabolite signals and hormone concentrations (accuracy = 0.79). In conclusion, serum metabolite levels and biochemical markers from a single blood sample possess modest predictive utility in differentiating LNSP from CAO pregnancies upon first presentation, which is improved by variable selection and combination using machine learning. A diagnostic test to confirm LNSP and thus exclude pregnancies affecting maternal morbidity and potentially life-threatening outcomes would be invaluable in emergency situations.

Updating M6 pregnancy of unknown location risk-prediction model including evaluation of clinical factors

OBJECTIVES

Ectopic pregnancy (EP) is a major high-risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to triage PUL as high vs low risk to guide appropriate follow-up. The M6 model is currently the best risk-prediction model. We aimed to update the M6 model and evaluate whether performance can be improved by including clinical factors.

METHODS

This prospective cohort study recruited consecutive PUL between January 2015 and January 2017 at eight units (Phase 1), with two centers continuing recruitment between January 2017 and March 2021 (Phase 2). Serum samples were collected routinely and sent for β-human chorionic gonadotropin (β-hCG) and progesterone measurement. Clinical factors recorded were maternal age, pain score, bleeding score and history of EP. Based on transvaginal ultrasonography and/or biochemical confirmation during follow-up, PUL were classified subsequently as failed PUL (FPUL), intrauterine pregnancy (IUP) or EP (including persistent PUL (PPUL)). The M6 models with (M6P ) and without (M6NP ) progesterone were refitted and extended with clinical factors. Model validation was performed using internal-external cross-validation (IECV) (Phase 1) and temporal external validation (EV) (Phase 2). Missing values were handled using multiple imputation.

RESULTS

Overall, 5473 PUL were recruited over both phases. A total of 709 PUL were excluded because maternal age was < 16 years or initial β-hCG was ≤ 25 IU/L, leaving 4764 (87%) PUL for analysis (2894 in Phase 1 and 1870 in Phase 2). For the refitted M6P model, the area under the receiver-operating-characteristics curve (AUC) for EP/PPUL vs IUP/FPUL was 0.89 for IECV and 0.84-0.88 for EV, with respective sensitivities of 94% and 92-93%. For the refitted M6NP model, the AUCs were 0.85 for IECV and 0.82-0.86 for EV, with respective sensitivities of 92% and 93-94%. Calibration performance was good overall, but with heterogeneity between centers. Net Benefit confirmed clinical utility. The change in AUC when M6P was extended to include maternal age, bleeding score and history of EP was between -0.02 and 0.01, depending on center and phase. The corresponding change in AUC when M6NP was extended was between -0.01 and 0.03. At the 5% threshold to define high risk of EP/PPUL, extending M6P altered sensitivity by -0.02 to -0.01, specificity by 0.03 to 0.04 and Net Benefit by -0.005 to 0.006. Extending M6NP altered sensitivity by -0.03 to -0.01, specificity by 0.05 to 0.07 and Net Benefit by -0.005 to 0.006.

CONCLUSIONS

The updated M6 model offers accurate diagnostic performance, with excellent sensitivity for EP. Adding clinical factors to the model improved performance in some centers, especially when progesterone levels were not suitable or unavailable. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Nano-Theranostic Modality for Visualization of the Placenta and Photo-Hyperthermia for Potential Management of Ectopic Pregnancy

Ectopic pregnancy (EP) is the leading cause of maternity-related death in the first trimester of pregnancy. Approximately 98% of ectopic implantations occur in the fallopian tube, and expedient management is crucial for preventing hemorrhage and maternal death in the event of tubal rupture. Current ultrasound strategies misdiagnose EP in up to 40% of cases, and the failure rate of methotrexate treatment for confirmed EP exceeds 10%. Here the first theranostic strategy for potential management of EP is reported using a near-infrared naphthalocyanine dye encapsulated within polymeric nanoparticles. These nanoparticles preferentially accumulate in the developing murine placenta within 24 h following systemic administration, and enable visualization of implantation sites at various gestational stages via fluorescence and photoacoustic imaging. These nanoparticles do not traverse the placental barrier to the fetus or impact fetal development. However, excitation of nanoparticles localized in specific placentas with focused NIR light generates heat (>43 °C) sufficient for disruption of placental function, resulting in the demise of targeted fetuses with no effect on adjacent fetuses. This novel approach would enable diagnostic confirmation of EP when current imaging strategies are unsuccessful, and elimination of EP could subsequently be achieved using the same nano-agent to generate localized hyperthermia resulting in targeted placental impairment.

An intrauterine genomic classifier reliably delineates the location of nonviable pregnancies

OBJECTIVE

To compare the intrauterine gene expression signatures of women with surgically confirmed ectopic pregnancy (ECT) and those of women with miscarriage to inform the development of a genomic classifier for the reliable delineation of pregnancy location in women with clinically nonviable pregnancies of unknown location (NV-PULs).

DESIGN

Discovery-based prospective cohort study.

SETTING

Academic medical center.

PATIENT(S)

Women with clinically nonviable early pregnancy to include abnormal intrauterine pregnancy (AIUP), ECT, or NV-PUL.

INTERVENTION(S)

Endometrial (EM) pipelle sampling of the uterus was conducted at the time of scheduled surgery for clinically nonviable early pregnancy (dilation and curettage, manual vacuum aspiration, or laparoscopy). All pregnancy locations were surgically and/or histologically confirmed as intrauterine or ectopic.

MAIN OUTCOME MEASURE(S)

Gene expression profiles as determined by array hybridization, quantitative real-time polymerase chain reaction, and nCounter technology.

RESULT(S)

Intrauterine samples were obtained by EM pipelle from 27 women undergoing surgery for a clinically nonviable early pregnancy. Comparison of array-based global gene expression signatures from women with histologically confirmed ECT versus AIUP revealed 61 differentially expressed genes from which the 5 most informative were included in the pregnancy location classifier. All 5 genes (C20orf85, LRRC46, RSPH4A, WDR49, and ZBBX) were cilia-associated and showed increased expression in pipelle samples from women with ECT relative to expression in samples from women with AIUP. The 5-gene classifier demonstrated an average area under the receiver operator characteristic curve of 0.97 for the detection of ECT. In an external test set composed of publicly available EM pipelle-based gene expression data from a study with similar ECT and AIUP cohorts (n = 19), the classifier revealed an average area under the receiver operator characteristic curve of 0.84.

CONCLUSION(S)

Consistently increased expression of cilia-associated genes in the uterine cavity of women with ECT provides a reliable molecular signal for the delineation of pregnancy location in women with clinically assessed NV-PUL. A classifier consisting of the 5 most informative cilia-associated genes demonstrated 91% (42/46) accuracy in predicting the pregnancy location.

Rectal ectopic pregnancy: A case report

RATIONALE

Abdominal ectopic pregnancy is a very rare form of ectopic pregnancy, yet is associated with higher morbidity due to atypical clinical presentation and misdiagnosis. In this report, we present a case of abdominal ectopic pregnancy with placenta invading to the rectal wall.

PATIENT CONCERNS

A 32-year-old woman was admitted to our hospital with an increasing serum ß-hCG level after diagnostic laparoscopy for ectopic pregnancy in the provincial hospital. During the laparoscopy, no gestational sac was found. She was discharged and scheduled for a follow-up visit to assess the level of ß-hCG. One week later, her serum ß-hCG level increased from 7000 IU/l to 12000 IU/l. Transvaginal Doppler ultrasound and abdominal computed tomography (CT) angiography demonstrated a right adnexal mass adherent to the rectal wall.

DIAGNOSIS

A rectal ectopic pregnancy is suspected.

INTERVENTIONS

Laparoscopic surgery was successfully performed in our hospital to remove the products of conception.

OUTCOMES

Histologic examination confirmed the diagnosis of a rectal ectopic pregnancy. The patient had an uneventful recovery and was discharged the next few days.

LESSONS

This case report reveals that an abdominal pregnancy is remarkably difficult to diagnose and manage. The gynecologists need to be aware of the possibility of gestational sac between the uterus and the rectum. To make early diagnosis of abdominal pregnancy, they need to combine clinical findings, imaging techniques (ultrasound, CT, MRI) and serial human chorionic gonadotropin measurements. Laparoscopic management should be considered in early abdominal pregnancy. A multidisciplinary team of gynecologists and gastrointestinal surgeons is required to deal with rectal ectopic pregnancy.

Primary hepatic ectopic pregnancy in a patient with polycystic ovary syndrome: A case report

RATIONALE

Hepatic ectopic pregnancy is an extremely rare ectopic pregnancy. This study aimed to report a case of primary hepatic pregnancy in a patient with polycystic syndrome.

PATIENT CONCERNS

A 30-year-old woman presented with vaginal bleeding after 63 days of amenorrhea.

DIAGNOSIS

The patient was initially diagnosed with liver ectopic pregnancy using abdominal ultrasound and abdominal computed tomography (CT).

INTERVENTIONS

The patient underwent laparoscopic exploration to reconfirm the gestational sac in the liver and abdominal surgery to remove liver gestation. The postoperative review of abdominal CT and the level of serum human chorionic gonadotropin (hCG) was performed.

OUTCOMES

The postoperative pathological examination revealed a fluffy tissue in the liver tissue and a blood clot. The patient's vital signs were normal, and she was advised regular follow-up after discharge from the hospital. One month later, the serum hCG level reduced to 0.32 mIU/mL (reference range 0-5 mIU/mL).

LESSONS

If the level of beta-human chorionic gonadotropin (β-HCG) is higher than normal in women of childbearing age and no gestational sac is found in the uterine cavity, the location of pregnancy and gestational sac should be positively confirmed. Also, the possibility of ectopic pregnancy in the abdominal cavity should be considered, and the relevant imaging and biochemical examinations should be improved to avoid delay in diagnosis and treatment.

Successful laparoscopic management of diaphragmatic pregnancy:a rare case report and brief review of literature

BACKGROUND

Abdominal ectopic pregnancies are rare category of ectopic pregnancies.We describe a ectopic pregnancy implanted on the surface of diaphragm and highlight the difficult clinical course of an abdominal ectopic pregnancy managed with strategic procedural intervention.

CASE PRESENTATION

A 33-year-old Chinese woman with abdominal pain was diagnosed with ectopic pregnancy implanted in the liver according to CT and advised to transfer the patient to tertiary referral center. The patient had a significant increasing abdominal pain and intense reflex sensitivity in the right shoulder when she presented to our hospital. Laparoscopic surgery was decided immediately with the impression of ruptured abdominal pregnancy and hemorrhagic shock. It was found that ectopic pregnancy was implanted on the diaphragmatic surface.The pregnant tissue was completely resected from the diaphragm and bipolar electrocoagulation was used to control bleeding. The patient was stable and discharged 3 days after surgery in a good condition.

CONCLUSION

CT or MRI should be considered as an alternative to TVS in the management of ectopic pregnancy patients with unusual presentations. A thorough observation of the entire pelvis and upper abdomen during laparoscopic exploration is crucial for diagnosis.

Vinorelbine Potently Induces Placental Cell Death, Does Not Harm Fertility and is a Potential Treatment for Ectopic Pregnancy

Ectopic pregnancies complicate 1–2 pregnancies and are a leading cause of maternal death. An effective oral drug therapy that replaces surgery might make its treatment safer, cheaper, simpler and therefore more widely accessible. The only current medical treatment offered to women is intramuscular methotrexate, but this only reliably resolves smaller ectopic pregnancies. As such, many ectopic pregnancies require surgical excision. We show that vinorelbine, an orally available chemotherapeutic agent, potently induced placental cell death but did not harm fertility in mice. Vinorelbine was 100–1000 times more potent than methotrexate in inducing placental cell death in vitro, and more potent than combination methotrexate and gefitinib (another proposed treatment for ectopic pregnancy being evaluated in phase III trials). Mechanistically, it caused microtubule condensation, blocked mitosis and activated the apoptosis cascade in placental cells. Vinorelbine was more efficacious than methotrexate ± gefitinib in reducing the volume of placental cell tumors xenografted subcutaneously in SCID mice. Mice exposed to vinorelbine and allowed to breed, following a four week washout period, displayed normal fertility, however long-term fertility was not assessed. Human Fallopian tubes treated with vinorelbine did not exhibit up-regulation of apoptosis molecules. Our findings show that placental cells appear sensitive to vinorelbine and it has potential as a tablet-only approach to treat ectopic pregnancy.

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We have identified vinorelbine, a well tolerated chemotherapeutic, as a potential therapeutic for ectopic pregnancy.

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Vinorelbine potently reduced placental cell viability in-vitro and in-vivo and proved more efficacious than the current medical therapeutic.

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Vinorelbine did not impact upon subsequent fertility in a mouse breeding model.

Ectopic pregnancy occurs when a conceptus implants outside of the womb. They are life threating and are a leading cause of maternal death in early pregnancy. Currently, the large majority of ectopic pregnancies are removed surgical, partly owing to the limited efficacy of the only available medical therapeutic, methotrexate. Here, we have identified a potential new medical therapeutic for ectopic pregnancy, vinorelbine. Vinorelbine, which is orally available chemotherapeutic, reduced placental cell viability both in-vitro and in-vivo and did not impact upon mice fertility in a breeding model. As such, vinorelbine may be an efficacious treatment for ectopic pregnancy and further human studies into its application are warranted.

Preferences and Outcomes for Chemotherapy Teaching in a Postgraduate Obstetrics and Gynecology Training Program

PURPOSE

To determine whether chemotherapy teaching is a desired component of postgraduate training programs in obstetrics and gynecology and assess its effect on practicing clinicians.

METHOD

After obtaining institutional review board approval, 99 individuals who completed postgraduate training at a single academic medical center between 2005 and 2013 were invited to complete an online survey. Descriptive statistics were used to summarize responses.

RESULTS

Of the 99 individuals, 68 (68%) completed the survey. Respondents included physicians currently practicing in both academic medicine (n = 36, 52.9%) and private practice (n = 24, 35.2%). Most respondents (n = 60, 88.2%) indicated that chemotherapy teaching was a desired feature of their training and expressed a preference for both formal didactics and direct clinical involvement (n = 55, 80.2%). Benefits identified by respondents included improved insight into the management of symptoms commonly associated with chemotherapy (n = 55, 82.1%) and an enhanced ability to counsel patients referred for oncology care (n = 48, 70.5%). All respondents who pursued training in gynecologic oncology following residency (n = 6) indicated that chemotherapy teaching favorably affected their fellowship experience. Of the 6 gynecologic oncologists, 3 (50%) who responded also indicated that chemotherapy teaching during residency improved their performance in fellowship interviews.

CONCLUSION

Chemotherapy teaching was a desired feature of postgraduate training in general obstetrics and gynecology at the institution studied. Consideration should be given to creating curricula that incorporate the principles and practice of chemotherapy and address the needs of obstetrics and gynecology trainees who intend to pursue both general and subspecialty practice.

Ectopic pregnancy secondary to in vitro fertilisation-embryo transfer: pathogenic mechanisms and management strategies

BACKGROUND

Ectopic pregnancy (EP) is the leading cause of maternal morbidity and mortality during the first trimester and the incidence increases dramatically with in vitro fertilisation and embryo transfer (IVF-ET). The co-existence of an EP with a viable intrauterine pregnancy (IUP) is known as heterotopic pregnancy (HP) affecting about 1% of patients during assisted conception. EP/HP can cause significant morbidity and occasional mortality and represent diagnostic and therapeutic challenges, particularly during fertility treatment. Many risk factors related to IVF-ET techniques and the cause of infertility have been documented. The combination of transvaginal ultrasound (TVS) and serum human chorionic gonadotrophin (hCG) is the most reliable diagnostic tool, with early diagnosis of EP/HP permitting conservative management. This review describes the risk factors, diagnostic modalities and treatment approaches of EP/HP during IVF-ET and also their impact on subsequent fertility treatment.

METHODS

The scientific literature was searched for studies investigating EP/HP during IVF-ET. Publications in English and within the past 6 years were mostly selected.

RESULTS

A history of tubal infertility, pelvic inflammatory disease and specific aspects of embryo transfer technique are the most significant risk factors for later EP. Early measurement of serum hCG and performance of TVS by an expert operator as early as gestational week 5 can identify cases of possible EP. These women should be closely monitored with repeated ultrasound and hCG measurement until a diagnosis is reached. Treatment must be customised to the clinical condition and future fertility requirements of the patient. In cases of HP, the viable IUP can be preserved in the majority of cases but requires early detection of HP. No apparent negative impact of the different treatment approaches for EP/HP on subsequent IVF-ET, except for risk of recurrence.

CONCLUSIONS

EP/HP are tragic events in a couple's reproductive life, and the earlier the diagnosis the better the prognosis. Due to the increase incidence following IVF-ET, there is a compelling need to develop a diagnostic biomarker/algorithm that can predict pregnancy outcome with high sensitivity and specificity before IVF-ET to prevent and/or properly manage those who are at higher risk of EP/HP.