The management of early pregnancy complications

Investigation of clinical utility of contrast-enhanced MRI in the diagnosis of ectopic pregnancy

AIM

To investigate whether contrast-enhanced (CE)-magnetic resonance imaging (MRI) improves identification of implantation site of ectopic pregnancy.

MATERIALS AND METHODS

This retrospective study enrolled 63 patients in whom implantation sites had been confirmed at histopathology. Two expert radiologists for gynaecological imaging and two inexpert radiologists independently reviewed non-CE MRI and a combination of non-CE and CE-MRI (non-CE+CE-MRI), then determined implantation site with a confidence level. The following MRI features were also evaluated: extrauterine gestational sac (GS)-like structure (shape, signal intensities at T1-weighted imaging [WI], T2WI, and diffusion-weighted imaging [DWI], presence of the three rings appearance, and distinct low intensity areas at T2WI, presence of tree or dot-like components, degree of contrast enhancement), fallopian tube (dilatation, dilatation with haematoma, degree of contrast enhancement, enhanced components within the tube), and ascites. These findings were compared for non-CE and non-CE+CE-MRI data, and for expert and inexpert groups.

RESULTS

The expert group identified implantation sites correctly in 58/63 (92%) cases for non-CE and non-CE+CE-MRI. In the inexpert group, the correct identification was improved from 54/63 (86%) using non-CE MRI to 58/63 (92%) using non-CE+CE-MRI, but was not significant (p=0.29). In comparison between non-CE and non-CE+CE-MRI, dilation of the fallopian tubes was observed more frequently (p=0.004) and the confidence level was elevated significantly in the non-CE+CE-MRI (p<0.0001) in the inexpert group. Intergroup comparison revealed that confidence level was significantly higher in the expert group than in the inexpert group using non-CE MRI (p<0.0001), although the difference was not significant at non-CE+CE MRI (p=0.49).

CONCLUSION

CE-MRI did not significantly improve correct identification of ectopic pregnancy implantation sites, although the addition of contrast enhancement did enable inexpert radiologists to diagnose confidently.

Magnetic resonance imaging of common, uncommon, and rare implantation sites in ectopic pregnancy

OBJECTIVE

To review the MRI appearances of tubal and non-tubal implantation sites in ectopic pregnancy.

CONCLUSION

Transvaginal ultrasound is the primary imaging modality in ectopic pregnancy and MRI is used as a problem-solving tool in selected indications as detailed in the article. MRI features of tubal, interstitial, cervical, cesarean scar, cornual, ovarian, abdominal, and heterotopic pregnancies are provided to familiarize the radiologists with their appearances thereby assisting them in making early and accurate diagnosis.

Cervicoisthmic pregnancy near cesarean scar after oocyte donation in premature ovarian failure: literature review starting from a single case

OBJECTIVE

This study aimed to identify the best management options in decision making in cases of cervicoisthmic and cesarean scar pregnancies and rare forms of ectopic pregnancies with high rates of pregnancy-related morbidity in the first trimester, more commonly associated with assisted reproductive medicine.

MATERIALS AND METHODS

We performed a literature review of the description of a case report of a cervicoisthmic pregnancy near a cesarean scar in a premature ovarian failure woman. She obtained pregnancy after ovum donation, hormonal therapy, and in vitro fertilization. The researchers focused on the MEDLINE/PubMed database articles on ectopic pregnancies, particularly on cesarean scar pregnancies, cervical pregnancies, and ectopic pregnancies after in vitro fertilization in English-language journals published from January 1996 to December 2011.

RESULTS

The conservative or nonconservative options for medical or surgical treatments are disposables. Moreover, in literature, no consensus was found about the best treatment method.

CONCLUSIONS

Obstetricians should pay great attention to a possible cesarean scar pregnancy in patients with risk factors in their medical history. Until now, the rarity of these findings does not allow the definition of a commonly accepted management, so the best personalized approach may be guided by early recognition, close surveillance, and appropriate counseling. Further investigations are necessary to recognize high-risk factors for all ectopic pregnancies and those unique to cesarean scar ectopic pregnancies.

Ectopic pregnancy: a review

PURPOSE

Ectopic pregnancy (EP) presents a major health problem for women of child-bearing age. EP refers to the pregnancy occurring outside the uterine cavity that constitutes 1.2-1.4 % of all reported pregnancies. All identified risk factors are maternal: pelvic inflammatory disease, Chlamydia trachomatis infection, smoking, tubal surgery, induced conception cycle, and endometriosis. These developments have provided the atmosphere for trials using methotrexate as a non-surgical treatment for EP. The diagnosis measure of EP is serum human chorionic gonadotropin, urinary hCGRP/i-hCG, progesterone measurement, transvaginal ultrasound scan, computed tomography, vascular endothelial growth factor, CK, disintegrin and metalloprotease-12 and hysterosalpingography. The treatment option of EP involves surgical treatment by laparotomy or laparoscopy, medical treatment is usually systemic or through local route, or by expectant treatment.

RESULTS

It was concluded that review data reflect a decrease in surgical treatment and not an actual decline in EP occurrence so that further new avenues are needed to explore early detection of the EP.

The term "pregnancy of unknown location" is here to stay

The term "pregnancy of unknown location" is an ultrasound classification and not a final diagnosis. The use of this terminology is here to stay and should continue as long as there is an appreciation for what it really means. It is the responsibility of the clinician, who follows up these women with a PUL, to ensure that a final diagnosis is achieved while preserving the well-being of these women.

Ultrasound diagnosis of ectopic pregnancy

Ectopic pregnancy (EP) remains the number one cause of first trimester maternal death. Traditionally, laparoscopy has been the gold standard for diagnosis of EP. The advent of high-resolution transvaginal scan (TVS) means more clinically stable women with EPs are diagnosed earlier, well before surgery becomes necessary in many cases. Early diagnosis by TVS is therefore potentially life saving and can reduce surgical morbidity by allowing elective surgery or even non-surgical conservative treatment options. Combining transabdominal and transvaginal scanning confers no benefit over transvaginal scanning alone. Reports that reads "…empty uterus, ectopic pregnancy cannot be excluded" should be a thing of the past. Diagnosis of EP should be based upon the positive identification of an adnexal mass using TVS rather than the absence of an intra-uterine gestational sac. A systematic approach to scanning the early pregnancy pelvis will diagnose the vast majority of EPs at the initial scan. Ultrasound, and in particular TVS, is fast becoming the new gold standard for diagnosis of all types of EP. In modern management, laparoscopy should be seen as the operative tool of choice while TVS the diagnostic tool of choice.

Diagnosis of ectopic pregnancy with ultrasound

Transvaginal sonography (TVS) is now the imaging modality of choice for the diagnosis of ectopic pregnancy with overall reported sensitivities of>90%. Specific sonographic criteria exist for the diagnosis of tubal and non-tubal pregnancies including cervical and caesarean section scar pregnancies. Diagnosis is based on the visualization of an ectopic mass rather than the inability to visualize an intra-uterine pregnancy. This chapter discusses the specific criteria used for the diagnosis of ectopic pregnancy and examines the literature assessing the accuracy of ultrasound as a diagnostic tool.

MR features of ectopic pregnancy

Ectopic pregnancy (EP), in which a fertilized ovum implants outside the uterine cavity, is the leading cause of pregnancy-related death in the first trimester. EP is usually suspected by a positive pregnancy test and an empty uterus on transvaginal sonography (TVS). Although TVS is the initial modality of choice, it may occasionally fail to demonstrate the implantation site. When TVS findings are indeterminate, magnetic resonance imaging (MRI) may provide better delineation of the focus of EP owing to its excellent tissue contrast. The key MRI features of EP include gestational sac (GS)-like structures that typically appear as a cystic sac-like structure, frequently associated with surrounding acute hematoma of distinct low intensity on T2-weighted images. In tubal pregnancy, an enhanced tubal wall on postcontrast images may be another diagnostic finding. Ruptured EP is inevitably associated with acute hematoma outside these structures. In intrauterine EP, recognition of the relationship between GS-like structure and the myometrium can aid in differentiating from normal pregnancy. Diagnostic pitfalls include heterotopic pregnancy, decidual changes in endometrial cyst and theca lutein cysts mimicking GS-like structures. Knowledge of a spectrum of clinical and MRI features of EP is essential for establishing an accurate diagnosis and determining appropriate management.

Surgical considerations in early pregnancy: ectopic pregnancy and ovarian torsion

Ectopic pregnancy and ovarian torsion are 2 of the most common causes of acute abdominal pain in early pregnancy. The following article will discuss the physiology and pathophysiology, evaluation, diagnosis, clinical management options, and nursing considerations for ovarian torsion and ectopic pregnancy. Both conditions require timely diagnosis to prevent mortality and minimize morbidity, and both may require surgical management.

The conservative management of cervical ectopic pregnancies

OBJECTIVE

To evaluate the role of conservative management in the treatment of cervical ectopic pregnancies.

METHODS

This was a retrospective analysis of all cervical ectopic pregnancies diagnosed in women attending our early pregnancy unit between April 1997 and September 2004 inclusive. The diagnosis of cervical ectopic pregnancy was made using transvaginal ultrasound. Clinical and demographic data were recorded in all cases. Serum human chorionic gonadotropin levels were measured at presentation and monitored subsequently to determine the rate of successful resolution. Conservative management was in the form of medical or expectant management. Medical management involved administration of systemic or intra-amniotic methotrexate, with or without intra-amniotic potassium chloride. Systemic methotrexate was either a single dose of 50 mg/m2 or an alternate-day regimen of methotrexate at 1 mg/kg (days 1,3,5) with folinic acid rescue (days 2,4,6). If intra-amniotic treatment was required, this was either 50 mg methotrexate or 5 mmol/L potassium chloride.

RESULTS

Seven cervical ectopic pregnancies were diagnosed during the study period. Three cases were managed successfully with a single dose of methotrexate. One case was managed successfully using a multiple-dose methotrexate regimen. Another case failed medical management with both the single- and multiple-dose regimens but was successfully treated after potassium chloride was given intra-amniotically under ultrasound guidance. One case was successfully treated with intra-amniotic methotrexate and another was managed expectantly. There was no associated morbidity or mortality during the study period. We also performed a review of the current literature.

CONCLUSION

The conservative management of cervical ectopic pregnancy is effective and safe.

Diagnostic accuracy of varying discriminatory zones for the prediction of ectopic pregnancy in women with a pregnancy of unknown location

OBJECTIVES

Various serum human chorionic gonadotropin (hCG) discriminatory zones are currently used for evaluating the likelihood of an ectopic pregnancy in women classified as having a pregnancy of unknown location (PUL) following a transvaginal ultrasound examination. We evaluated the diagnostic accuracy of discriminatory zones for serum hCG levels of > 1000 IU/L, 1500 IU/L and 2000 IU/L for the detection of ectopic pregnancy in such women.

METHODS

This was a prospective observational study of women who were assessed in a specialized transvaginal scanning unit. All women with a PUL had serum hCG measured at presentation. Expectant management of PULs was adopted. These women were followed up with transvaginal ultrasound, monitoring of serum hormone levels and laparoscopy until a final diagnosis was established: a failing PUL, an intrauterine pregnancy (IUP), an ectopic pregnancy or a persisting PUL. The persisting PULs probably represented ectopic pregnancies which had been missed on ultrasound and these were incorporated into the ectopic pregnancy group. Three different discriminatory zones (1000 IU/L, 1500 IU/L and 2000 IU/L) were evaluated for predicting ectopic pregnancy in this PUL population.

RESULTS

A total of 5544 consecutive women presented to the early pregnancy unit between 25 June 2001 and 14 April 2003. Of these, 569 (10.3%) women were classified as having a PUL, 42 of which were lost to follow up. Of the 527 (9.5%) cases with PUL analyzed, there were 300 (56.9%) failing PULs, 181 (34.3%) IUPs and 46 (8.7%) ectopic pregnancies. Overall, 74.6% were symptomatic and 25.4% were asymptomatic (P = 8.825E-07). The sensitivity and specificity of an hCG level of > 1000 IU/L to detect ectopic pregnancy were 21.7% (10/46) and 87.3% (420/481), respectively; for an hCG level of > 1500 IU/L these values were 15.2% (7/46) and 93.4% (449/481), respectively, and for an hCG level of > 2000 IU/L they were 10.9% (5/46) and 95.2% (458/481), respectively.

CONCLUSIONS

Varying the discriminatory zone does not significantly improve the detection of ectopic pregnancy in a PUL population. A single measurement of serum hCG is not only potentially falsely reassuring but also unhelpful in excluding the presence of an ectopic pregnancy.

Do levels of serum cancer antigen 125 and creatine kinase predict the outcome in pregnancies of unknown location?

BACKGROUND

The aim of this study was to evaluate the role of maternal serum cancer antigen 125 (CA 125) and creatine kinase (CK) levels in predicting the outcome of pregnancies of unknown location (PUL).

METHODS

Prospective observational study. Women classified as PUL were recruited. Final outcome of each PUL was established: failing PUL, intrauterine pregnancy (IUP), ectopic pregnancy (EP) or persisting PUL. The persisting PUL group almost certainly represent ultrasonically missed EP and were included in EP group. Serum CK and CA 125 were measured at 0 and 48 h. The values at presentation and the change in levels after 2 days were used in the analysis. We incorporated the most significant of variables into a multinomial logistic regression model to predict all outcomes. The performance of this model was evaluated using receiver operating characteristic (ROC) curves.

RESULTS

In all, 4698 consecutive women were scanned; 403 were classified as PUL, 27 were lost to follow-up. Of the 376 women eligible, 297 had complete data and therefore were recruited. Mean age and mean gestation were 30.0 years and 43.3 days respectively. Final outcomes: 153 failing PUL (51.5%), 116 IUP (39.1%) and 28 EP (9.4%). Mean serum CK levels at 0 and 48 h were 88.5 and 86.8 IU/l respectively. Mean serum CA 125 levels at 0 and 48 h were 43.8 and 40.1 kIU/l respectively. 81.1% of women had CK and CA 125 ratios (CK 48 h/CK 0 h, CA 125 48 h/CA125 0 h) between 0.7 and 1.3. CA 125 ratio was the only significant variable in the three outcome groups (P < 0.0001). Logistic regression analysis incorporating CA 125 ratio gave an area under ROC curve of 0.782 (SE = 0.041) for failing PUL, 0.768 (SE = 0.043) for IUP and 0.560 (SE = 0.078) for EP. This model was capable of distinguishing failing PUL from IUP, but was not able to detect EP.

CONCLUSIONS

Absolute levels of serum CK and CA 125 at the defined times cannot be used to predict the outcome of PUL. Although the CA 125 ratio when incorporated into logistic regression model can distinguish failing PUL from IUP, its inability to detect the high risk PUL, i.e. the developing EP, renders it inappropriate for use in the clinical setting.

A prospective evaluation of a single-visit strategy to manage pregnancies of unknown location

BACKGROUND

The aim was to assess whether women with a pregnancy of unknown location (PUL) can be safely excluded from potentially unnecessary multiple clinic visits.

METHODS

A single-visit protocol was developed based upon data from 200 consecutive PULs. PULs were divided into groups according to the probable risk of ectopic pregnancy. Those PULs with an initial serum progesterone < or =10 nmol/l or a serum HCG of < or =25 U/l were deemed to be at low risk and classified as resolving or failing PULs. Those PULs with an initial serum progesterone of >50 nmol/l, regardless of serum HCG, were thought to be a probable intra-uterine pregnancy (IUP) and were also classified as being low risk. Those PULs with an initial serum progesterone of 10-50 nmol/l and a serum HCG of >25 U/l were classified as being at high risk. This protocol was then tested prospectively on 318 consecutive PULs. Management was based solely on the basis of an initial transvaginal ultrasound scan (TVS) and a single measurement of HCG and progesterone taken at the time of initial consultation.

RESULTS

A total of 5544 consecutive women were scanned, of which 560 (10.1%) women were classified as PULs. Forty-two were lost to follow-up and therefore 518 (9.34%) were analysed. In the training set of 200 PULs, there were 111 (55.5%) failing PULs, 67 (33.5%) IUPs and 22 (11%) ectopic pregnancies. In the test set of 318, there were 189 (59.4%) failing PULs, 114 (35.8%) IUPs and 15 (4.7%) ectopic pregnancies. For the training group, the sensitivity and specificity of a single visit to detect low-risk PULs were 77 and 82%, respectively. The positive (PPV) and negative predictive values (NPV) were 97 and 31%, respectively. For the test group of 318 PULs, the sensitivity and specificity were 84 and 33%, respectively. The PPV and NPV were 96 and 9.4%, respectively.

CONCLUSIONS

A single-visit strategy based on commonly used criteria eliminates 84% of non-ectopic pregnancies correctly from the system. However, as 67% of ectopic pregnancies are discharged without adequate follow-up, a single-visit strategy should not be used as an alternative to the current multi-visit strategy used in most units.

The use of a new logistic regression model for predicting the outcome of pregnancies of unknown location

BACKGROUND

The aim of this study was to generate and evaluate new logistic regression models from simple demographic and hormonal data to predict the outcome of pregnancies of unknown location (PULs).

METHODS

Data were collected prospectively from 185 consecutive women classified as having a PUL by transvaginal scan; blood was taken at presentation and 48 h later to measure serum progesterone and HCG. These women were followed-up until the outcome was established: an intrauterine pregnancy (IUP), an ectopic pregnancy (EP) or a failing PUL. Three multi-categorical logistic regression models were tested. M1 was based on the HCG ratio (rate of change in HCG over 48 h), M2 was based on the average progesterone level (the mean of the progesterone level at 0 and 48 h) and M3 was based on the patient's age.

RESULTS

A total of 102 failing PULs, 63 IUPs and 20 EPs were used in the training set to develop the new models. The best of these models, M3, gave a retrospective area under the receiver operating characteristic (ROC) curve of 0.984 for failing PUL, 0.995 for IUP and 0.920 for EP. All three models were tested prospectively on the test set of 196 cases. M1 outperformed M2 and M3 when tested prospectively. The area under the ROC curve (AUC) was 0.975 for failing PUL, 0.966 for IUP and 0.885 for EP. M1, for the detection of EP, had a sensitivity of 91.7%, a specificity of 84.2%, a positive likelihood ratio of 5.8, a positive predictive value of 27.5% and a negative predictive value of 99.4%.

CONCLUSIONS

The logistic regression model M1, can predict which PULs will become failing PULs, IUPs and, most importantly, EPs based on the patient's HCG ratio alone.