Midtrimester hemoperitoneum caused by placenta percreta in association with elevated maternal serum alpha-fetoprotein level

Placenta Accreta Spectrum Diagnosis Challenges and Controversies in Current Obstetrics: A Review

Background

Placenta accreta spectrum (PAS) is the most common obstetric complication in current obstetrics in which the placenta is fully or partially attached to the uterine myometrial layer at delivery. This is commonly due to the deficiency of the uterine interface between the uterine endometrial and myometrial layers leading to abnormal decidualization at the uterine scar area, which permits the abnormally placental anchoring villous and trophoblasts, deeply invade the myometrium. The prevalence of PAS is globally at rising trends every day in modern obstetrics originally due to the high increasing rate of cesarean sections, placenta previa, and assisted reproductive technology (ART). Thus, the early and precise diagnosis of PAS is imperative to prevent maternal intrapartum or postpartum bleeding complications.

Objective

The main aim of this review is to debate the current challenges and controversies in the routine diagnosis of PAS diseases in obstetrics.

Data Source

We retrospectively reviewed the recent articles on different methods of diagnosing PAS in PubMed, Google Scholar, Web of Science, Medline, Embase, and other website databases.

Results

Despite that, the standard ultrasound is a reliable and key tool for the diagnosis of PAS, the lack of ultrasound features does not exclude the diagnosis of PAS. Therefore, clinical assessment of risk factors, MRI tests, serological markers, and placental histopathological tests are also indispensable for the prediction of PAS. Previously, limited studies reached a high sensitivity rate of diagnosis PAS in appropriate cases, while many studies recommended the inclusion of different diagnosis methods to improve the diagnosis accuracy.

Conclusion

A multidisciplinary squad with well-experienced obstetricians, radiologists, and histopathologists should be involved in the establishment of the early and conclusive diagnosis of PAS.

Uterine body placenta accreta spectrum: A detailed literature review

Placenta accreta spectrum (PAS) is a major obstetrical problem whose incidence is rising. Current guidelines recommend screening of all women with placenta previa and risk factors for PAS between 20 and 24 weeks. Risk factors, diagnosis, and management of previa PAS are well established, but an apparently normal location of the placenta does not exclude PAS. Literature data are scarce on uterine body PAS, which carries a high risk of maternal and neonatal adverse outcome, but is still easily missed on prenatal ultrasound. We conducted a comprehensive review to identify possible risk factors, clinical presentations, and diagnostic modalities of uterine PAS. A total of 133 cases were found during a 70-year period (1949-2019). The vast majority of them presented with signs of uterine rupture, even prior to the viability threshold of 24 weeks (up to 45%). Major risk factors included previous cesarean delivery, uterine curettage, uterine surgery, Asherman's syndrome, manual removal of the placenta, endometritis, high parity, young maternal age, in vitro fertilization, radiotherapy, uterine artery embolization, and uterine leiomyoma. Diagnosis was pre-symptomatic in only 3% of cases. Future studies should differentiate between previa PAS and uterine body PAS.

Obstetrical complications associated with abnormal maternal serum markers analytes

OBJECTIVE

To review the obstetrical outcomes associated with abnormally elevated or decreased level of one or more of the most frequently measured maternal serum marker analytes used in screening for aneuploidy. To provide guidance to facilitate the management of pregnancies that have abnormal levels of one of more markers and to assess the usefulness of these markers as a screening test.

OPTIONS

Perinatal outcomes associated with abnormal levels of maternal serum markers analytes are compared with the outcomes of pregnancies with normal levels of the same analytes or the general population.

EVIDENCE

The Cochrane Library and Medline were searched for English-language articles published from 1966 to February 2007, relating to maternal serum markers and perinatal outcomes. Search terms included PAPP-A (pregnancy associated plasma protein A), AFP (alphafetoprotein), hCG (human chorionic gonadotropin), estriol, unconjugated estriol, inhibin, inhibin-A, maternal serum screen, triple marker screen, quadruple screen, integrated prenatal screen, first trimester screen, and combined prenatal screen. All study types were reviewed. Randomized controlled trials were considered evidence of the highest quality, followed by cohort studies. Key individual studies on which the recommendations are based are referenced. Supporting data for each recommendation are summarized with evaluative comments and references. The evidence was evaluated using the guidelines developed by the Canadian Task Force on Preventive Health Care.

VALUES

The evidence collected was reviewed by the Genetics Committee of the Society of Obstetricians and Gynaecologists of Canada.

BENEFITS, HARMS, AND COSTS

The benefit expected from this guideline is to facilitate early detection of potential adverse pregnancy outcomes when risks are identified at the time of a maternal serum screen. It will help further stratification of risk and provide options for pregnancy management to minimize the impact of pregnancy complications. The potential harms resulting from such practice are associated with the so called false positive (i.e., uncomplicated pregnancies labelled at increased risk for adverse perinatal outcomes), the potential stress associated with such a label, and the investigations performed for surveillance in this situation. No cost-benefit analysis is available to assess costs and savings associated with this guideline. SUMMARY STATEMENTS: 1. An unexplained level of a maternal serum marker analyte is defined as an abnormal level after confirmation of gestational age by ultrasound and exclusion of maternal, fetal, or placental causes for the abnormal level. (III) 2. Abnormally elevated levels of serum markers are associated with adverse pregnancy outcomes in twin pregnancies, after correction for the number of fetuses. Spontaneous or planned mutifetal reductions may result in abnormal elevations of serum markers. (II-2) RECOMMENDATIONS: 1. In the first trimester, an unexplained low PAPP-A (< 0.4 MoM) and/or a low hCG (< 0.5 MoM) are associated with an increased frequency of adverse obstetrical outcomes, and, at present, no specific protocol for treatment is available. (II-2A) In the second trimester, an unexplained elevation of maternal serum AFP (> 2.5 MoM), hCG (> 3.0 MoM), and/or inhibin-A (> or =2.0 MoM) or a decreased level of maternal serum AFP (< 0.25 MoM) and/or unconjugated estriol (< 0.5 MoM) are associated with an increased frequency of adverse obstetrical outcomes, and, at present, no specific protocol for treatment is available. (II-2A) 2. Pregnant woman with an unexplained elevated PAPP-A or hCG in the first trimester and an unexplained low hCG or inhibin-A and an unexplained elevated unconjugated estriol in the second trimester should receive normal antenatal care, as this pattern of analytes is not associated with adverse perinatal outcomes. (II-2A) 3. The combination of second or third trimester placenta previa and an unexplained elevated maternal serum AFP should increase the index of suspicion for placenta accreta, increta, or percreta. (II-2B) An assessment (ultrasound, MRI) of the placental-uterine interface should be performed. Abnormal invasion should be strongly suspected, and the planning of delivery location and technique should be done accordingly. (III-C) 4. A prenatal consultation with the medical genetics department is recommended for low unconjugated estriol levels (<0.3 MoM), as this analyte pattern can be associated with genetic conditions. (II-2B) 5. The clinical management protocol for identification of potential adverse obstetrical outcomes should be guided by one or more abnormal maternal serum marker analyte value rather than the false positive screening results for the trisomy 21 and/or the trisomy 18 screen. (II-2B) 6. Pregnant woman who are undergoing renal dialysis or who have had a renal transplant should be offered maternal serum screening, but interpretation of the result is difficult as the level of serum hCG is not reliable. (II-2A) 7. Abnormal maternal uterine artery Doppler in association with elevated maternal serum AFP, hCG, or inhibin-A or decreased PAPP-A identifies a group of women at greater risk of IUGR and gestational hypertension with proteinuria. Uterine artery Doppler measurements may be used in the evaluation of an unexplained abnormal level of either of these markers. (II-2B) 8. Further research is recommended to identify the best protocol for pregnancy management and surveillance in women identified at increased risk of adverse pregnancy outcomes based on an abnormality of a maternal serum screening analyte. (III-A) 9. In the absence of evidence supporting any specific surveillance protocol, an obstetrician should be consulted in order to establish a fetal surveillance plan specific to the increased obstetrical risks (maternal and fetal) identified. This plan may include enhanced patient education on signs and symptoms of the most common complications, increased frequency of antenatal visits, increased ultrasound (fetal growth, amniotic fluid levels), and fetal surveillance (biophysical profile, arterial and venous Doppler), and cervical length assessment. (III-A) 10. Limited information suggests that, in women with elevated hCG in the second trimester and/or abnormal uterine artery Doppler (at 22-24 weeks), low-dose aspirin (60-81 mg daily) is associated with higher birthweight and lower incidence of gestational hypertension with proteinuria. This therapy may be used in women who are at risk. (II-2B) 11. Further studies are recommended in order to assess the benefits of low-dose aspirin, low molecular weight heparin, or other therapeutic options in pregnancies determined to be at increased risk on the basis of an abnormal maternal serum screening analyte. (III-A) 12. Multiple maternal serum markers screening should not be used at present as a population-based screening method for adverse pregnancy outcomes (such as preeclampsia, placental abruption, and stillbirth) outside an established research protocol, as sensitivity is low, false positive rates are high, and no management protocol has been shown to clearly improve outcomes. (II-2D) When maternal serum screening is performed for the usual clinical indication (fetal aneuploidy and/or neural tube defect), abnormal analyte results can be utilized for the identification of pregnancies at risk and to direct their clinical management. (II-2B) Further studies are recommended to determine the optimal screening method for poor maternal and/or perinatal outcomes. (III-A).

Placenta percreta--two cases and review of the literature

Two cases of placenta pecreta confirmed histologically were treated conservatively with retention of the uterus. Both later went on to have successful pregnancies.

The management of placenta percreta: conservative and operative strategies

OBJECTIVE

Our purpose was to assess preferences for the management of placenta percreta and identify aspects of care related to an improved outcome.

STUDY DESIGN

Both an analysis of a questionnaire issued to members of the Society of Perinatal Obstetricians and a retrospective study at our institution were used to obtain case histories of women with placenta percreta during a recent 3-year period.

RESULTS

Fifty-five of the 109 cases (50%) reported by members of the Society of Perinatal Obstetricians were suspected ante partum. Complications associated with this disorder included uterine rupture (3 cases), transfusion of > 10 units (44 cases, 40%), ureteral ligation or fistula formation (5 cases each, 5%), infection (31 cases, 28%), perinatal death (10 cases, 9%), and maternal death (8 cases, 7%). Management options included surgical removal of the uterus and involved tissues (101 cases, 93%) and conservative treatment with the placenta left in situ after delivery (8 cases, 7%). More members of the Society of Perinatal Obstetricians responding to our survey opted for conservative management if adjacent tissues were involved (69% with extension into the bladder or gastrointestinal tract) compared with 31% when the percreta was confined to the uterus, p < 0.001. Conservative therapy was also associated with less blood loss in reported cases (median units red blood cells transfused, 0 vs 7, p = 0.003). Two of the three cases of placenta percreta at our institution were identified ante partum. The third case represents the first reported with antepartum identification of percreta followed by deliberate conservative treatment.

CONCLUSIONS

With greater involvement of surrounding tissues, conservative treatment was preferred in hemodynamically stable patients. If surgical excision of the placenta is attempted or necessary, physicians experienced in pelvic dissection must be involved because of the frequency of maternal morbidity and mortality.