Clinical Practice Guidelines and Recommendations by The World Association of Perinatal Medicine and Perinatal Medicine Foundation. Reporting Suspected Findings from Fetal Central Nervous System Examination

These guidelines follow the mission of the World Association of Perinatal Medicine, in collaboration with the Perinatal Medicine Foundation, which brings together groups and individuals worldwide, with the aim to improve prenatal detection of Central Nervous System anomalies and the appropriate referral of pregnancies with suspected fetal anomalies. In addition, this document provides further guidance for healthcare practitioners with the goal of standardizing the description of ultrasonographic abnormal findings.

First-trimester cesarean scar pregnancy: a comparative analysis of treatment options from the international registry

BACKGROUND

A cesarean scar pregnancy is an iatrogenic consequence of a previous cesarean delivery. The gestational sac implants into a niche created by the incision of the previous cesarean delivery, and this carries a substantial risk for major maternal complications. The aim of this study was to report, analyze, and compare the effectiveness and safety of different treatments options for cesarean scar pregnancies managed in the first trimester through a registry.

OBJECTIVE

This study aimed to evaluated the ultrasound findings, disease behavior, and management of first-trimester cesarean scar pregnancies.

STUDY DESIGN

We created an international registry of cesarean scar pregnancy cases to study the ultrasound findings, disease behavior, and management of cesarean scar pregnancies. The Cesarean Scar Pregnancy Registry collects anonymized ultrasound and clinical data of individual patients with a cesarean scar pregnancy on a secure, digital information platform. Cases were uploaded by 31 participating centers across 19 countries. In this study, we only included live and failing cesarean scar pregnancies (with or without a positive fetal heart beat) that received active treatment (medical or surgical) before 12+6 weeks' gestation to evaluate the effectiveness and safety of the different management options. Patients managed expectantly were not included in this study and will be reported separately. Treatment was classified as successful if it led to a complete resolution of the pregnancy without the need for any additional medical interventions.

RESULTS

Between August 29, 2018, and February 28, 2023, we recorded 460 patients with cesarean scar pregnancies (281 live, 179 failing cesarean scar pregnancy) who fulfilled the inclusion criteria and were registered. A total of 270 of 460 (58.7%) patients were managed surgically, 123 of 460 (26.7%) patients underwent medical management, 46 of 460 (10%) patients underwent balloon management, and 21 of 460 (4.6%) patients received other, less frequently used treatment options. Suction evacuation was very effective with a success rate of 202 of 221 (91.5%; 95% confidence interval, 87.8-95.2), whereas systemic methotrexate was least effective with only 38 of 64 (59.4%; 95% confidence interval, 48.4-70.4) patients not requiring additional treatment. Overall, surgical treatment of cesarean scar pregnancies was successful in 236 of 258 (91.5%, 95% confidence interval, 88.4-94.5) patients and complications were observed in 24 of 258 patients (9.3%; 95% confidence interval, 6.6-11.9).

CONCLUSION

A cesarean scar pregnancy can be managed effectively in the first trimester of pregnancy in more than 90% of cases with either suction evacuation, balloon treatment, or surgical excision. The effectiveness of all treatment options decreases with advancing gestational age, and cesarean scar pregnancies should be treated as early as possible after confirmation of the diagnosis. Local medical treatment with potassium chloride or methotrexate is less efficient and has higher rates of complications than the other treatment options. Systemic methotrexate has a substantial risk of failing and a higher complication rate and should not be recommended as first-line treatment.

WAPM-World Association of Perinatal Medicine Practice Guidelines: Fetal central nervous system examination

These practice guidelines follow the mission of the World Association of Perinatal Medicine in collaboration with the Perinatal Medicine Foundation, bringing together groups and individuals throughout the world, with the goal of improving the ultrasound assessment of the fetal Central Nervous System (CNS) anatomy. In fact, this document provides further guidance for healthcare practitioners for the evaluation of the fetal CNS during the mid-trimester ultrasound scan with the aim to increase the ability in evaluating normal fetal anatomy. Therefore, it is not intended to establish a legal standard of care. This document is based on consensus among perinatal experts throughout the world, and serves as a guideline for use in clinical practice.

WAPM-World Association of Perinatal Medicine practice guidelines: fetal central nervous system examination

These practice guidelines follow the mission of the World Association of Perinatal Medicine (WAPM) in collaboration with the Perinatal Medicine Foundation, bringing together groups and individuals throughout the world, with the goal of improving the ultrasound assessment of the fetal central nervous system (CNS) anatomy. In fact, this document provides further guidance for healthcare practitioners for the evaluation of the fetal CNS during the mid-trimester ultrasound scan with the aim to increase the ability in evaluating normal fetal anatomy. Therefore, it is not intended to establish a legal standard of care. This document is based on consensus among perinatal experts throughout the world, and serves as a guideline for use in clinical practice.

Risk factors, histopathology and diagnostic accuracy in posterior placenta accreta spectrum disorders: systematic review and meta-analysis

OBJECTIVE

To elucidate the risk factors, histopathological correlations and diagnostic accuracy of prenatal imaging in pregnancies complicated by posterior placenta accreta spectrum (PAS) disorders.

METHODS

MEDLINE, EMBASE and CINAHL were searched for studies reporting on women with posterior PAS. Inclusion criteria were women with posterior PAS confirmed either at surgery or on histopathological analysis. The outcomes explored were risk factors for posterior PAS, histopathological correlation and the diagnostic accuracy of ultrasound and magnetic resonance imaging (MRI) in detecting posterior PAS. Random-effects meta-analysis of proportions was used to analyze the data.

RESULTS

Twenty studies were included. Placenta previa was present in 92.8% (107/114; 17 studies) of pregnancies complicated by posterior PAS, while 76.1% (53/88; 11 studies) of women had had prior uterine surgery, mainly a Cesarean section (CS) or curettage and 82.5% (66/77; 10 studies) were multiparous. When considering histopathological analysis in women affected by posterior PAS, 77.5% (34/44; 11 studies) had placenta accreta, 19.5% (8/44; 11 studies) had placenta increta and 9.3% (2/44; 11 studies) had placenta percreta. Of the cases of posterior PAS disorder, 52.4% (31/63; 12 studies) were detected prenatally on ultrasound, while 46.7% (32/63; 12 studies) were diagnosed only at birth. When exploring the distribution of the classic ultrasound signs of PAS, placental lacunae were present in 39.0% (12/30; seven studies), loss of the clear zone in 41.1% (13/30; seven studies) and bladder-wall interruption in 16.6% (4/30; seven studies) of women, while none of the included cases showed hypervascularization at the bladder-wall interface. When assessing the role of MRI in detecting posterior PAS, 73.5% (26/32; 11 studies) of cases were detected on prenatal MRI, while 26.5% (6/32; 11 studies) were discovered only at the time of CS.

CONCLUSIONS

Placenta previa, prior uterine surgery and multiparity represent the most commonly reported risk factors for posterior PAS. Ultrasound had a very low diagnostic accuracy in detecting these disorders prenatally. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Outcome of cesarean scar pregnancy according to gestational age at diagnosis: A systematic review and meta-analysis

OBJECTIVE

The association between the most severe types of placenta accreta spectrum disorders and caesarean scar pregnancy (CSP) poses the question of whether early diagnosis may impact the clinical outcome of these anomalies. The aim of this study is to report the outcome of cesarean scar pregnancy (CSP) diagnosed in the early (≤9 weeks) versus late (>9 weeks) first trimester of pregnancy.

STUDY DESIGN

Medline, Embase and Clinicaltrail.gov databases were searched. Studies including cases of CSP with an early (≤9 weeks of gestation) compared to a late (>9 weeks) first trimester diagnosis of CSP, followed by immediate treatment, were included in this systematic review. The primary outcome was a composite measure of severe maternal morbidity including either severe first trimester bleeding, need for blood transfusion, uterine rupture or emergency hysterectomy. The secondary outcomes were the individual components of the primary outcome. Random-effect meta-analyses were used to combine data.

RESULTS

Thirty-six studies (724 women with CSP) were included. Overall, composite adverse outcome complicated 5.9 % (95 % CI 3.5-9.0) of CSP diagnosed ≤9 weeks and 32.4 % (95 % CI 15.7-51.8) of those diagnosed >9 weeks. Massive hemorrhage occurred in 4.3 % (95 % CI 2.3-7.0) of women with early and in 28.0 % (95 % CI 14.1-44.5) of those with late first trimester diagnosis of CSP, while the corresponding figures for the need for blood transfusion were 1.5 % (95 % CI 0.6-2.8) and 15.8 % (95 % CI 5.5-30.2) respectively. Uterine rupture occurred in 2.5 % (95 % CI 1.2-4.1) of women with a prenatal diagnosis of CSP ≤ 9 weeks and in 7.5 % (95 % CI 2.5-14.9) of those with CSP > 9 weeks, while an emergency intervention involving hysterectomy was required in 3.7 % (95 % CI 2.2-5.4) and 16.3 % (95 % CI5.9-30.6) respectively. When computing the risk, early diagnosis of CSP was associated with a significantly lower risk of composite adverse outcome, (OR: 0.14; 95 % CI 0.1-0.4 p < 0.001).

CONCLUSIONS

Early first trimester diagnosis of CSP is associated with a significantly lower risk of maternal complications, thus supporting a policy of universal screening for these anomalies in women with a prior cesarean delivery although the cost-effectiveness of such policy should be tested in future studies.

Reproductive outcome after cesarean scar pregnancy: A systematic review and meta-analysis

INTRODUCTION

To evaluate subsequent reproductive among women with a prior cesarean scar pregnancy (CSP).

MATERIAL AND METHODS

MEDLINE, Embase and ClinicalTrials.gov databases were searched. Inclusion criteria were women with a prior CSP, defined as the gestational sac or trophoblast within the dehiscence/niche of the previous cesarean section scar or implanted on top of it. The primary outcome was the recurrence of CSP; secondary outcomes were the chance of achieving a pregnancy after CSP, miscarriage, preterm birth, uterine rupture and the occurrence of placenta accreta spectrum disorders. Subgroup analysis according to the management of CSP (surgical vs non-surgical) was also performed. Random effect meta-analyses of proportions were used to analyze the data.

RESULTS

Forty-four studies (3598 women with CSP) were included. CSP recurred in 17.6% of women. Miscarriage, preterm birth and placenta accreta spectrum disorders complicated 19.1% (65/341), 10.3% (25/243) and 4.0% of pregnancies, and 67.0% were uncomplicated. When stratifying the analysis according to the type of management, CSP recurred in 21% of women undergoing surgical and in 15.2% of those undergoing non-surgical management. Placenta accreta spectrum disorders complicated 4.0% and 12.0% of cases, respectively.

CONCLUSIONS

Women with a prior CSP are at high risk of recurrence, miscarriage, preterm birth and placenta accreta spectrum. There is still insufficient evidence to elucidate whether the type of management adopted (surgical vs non-surgical) can impact reproductive outcome after CSP. Further large, prospective studies sharing an objective protocol of prenatal management and long-term follow up are needed to establish the optimal management of CSP and to elucidate whether it may affect its risk of recurrence and pregnancy outcome in subsequent gestations.

Interobserver agreement in MRI assessment of severity of placenta accreta spectrum disorders

OBJECTIVE

To evaluate the level of agreement in the prenatal magnetic resonance imaging (MRI) assessment of the presence and severity of placenta accreta spectrum (PAS) disorders between examiners with expertise in the diagnosis and management of these conditions.

METHODS

This was a secondary analysis of a prospective study including women with placenta previa or low-lying placenta and at least one prior Cesarean delivery or uterine surgery, who underwent MRI assessment at a regional referral center for PAS disorders in Italy, between 2007 and 2017. The MRI scans were retrieved from the hospital electronic database and assessed by four examiners, who are considered to be experts in the diagnosis and surgical management of PAS disorders. The examiners were blinded to the ultrasound diagnosis, histopathological findings and clinical data of the patients. Each examiner was asked to assess 20 features on the MRI scans, including the presence, depth and topography of placental invasion. Depth of invasion was defined as the degree of adhesion and invasion of the placenta into the myometrium and uterine serosa (placenta accreta, increta or percreta) and the histopathological examination of the removed uterus was considered the reference standard. Topography of the placental invasion was defined as the site of placental invasion within the uterus in relation to the posterior bladder wall (posterior upper bladder wall and uterine body, posterior lower bladder wall and lower uterine segment and cervix or no visible bladder invasion) and the site of invasion at surgery was considered the reference standard. The degree of interrater agreement (IRA) was evaluated by calculating both the percentage of observed agreement among raters and the Fleiss kappa (κ) value.

RESULTS

Forty-six women were included in the study. The median gestational age at MRI was 33.8 (interquartile range, 33.1-34.0) weeks. A final diagnosis of placenta accreta, increta and percreta was made in 15.2%, 17.4% and 50.0% patients, respectively. There was excellent agreement between the four examiners in the assessment of the overall presence of a PAS disorder (IRA, 92.1% (95% CI, 86.8-94.0%); κ, 0.90 (95% CI, 0.89-1.00)). However, there was significant heterogeneity in IRA when assessing the different MRI signs suggestive of a PAS disorder. There was excellent agreement between the examiners in the identification of the depth of placental invasion on MRI (IRA, 98.9% (95% CI, 96.8-100.0%); κ, 0.95 (95% CI, 0.89-1.00)). However, agreement in assessing the topography of placental invasion was only moderate (IRA, 72.8% (95% CI, 72.7-72.9%); κ, 0.56 (95% CI, 0.54-0.66)). More importantly, when assessing parametrial invasion, which is one of the most significant prognostic factors in women affected by PAS, the agreement was substantial and moderate in judging the presence of invasion in the coronal (IRA, 86.6% (95% CI, 86.5-86.7%); κ, 0.69 (95% CI, 0.59-0.71)) and axial (IRA, 78.6% (95% CI, 78.5-78.7%); κ, 0.56 (95% CI, 0.33-0.60)) planes, respectively. Likewise, interobserver agreement in judging the presence and the number of newly formed vessels in the parametrial tissue was moderate (IRA, 88.0% (95% CI, 88.0-88.1%); κ, 0.59 (95% CI, 0.45-0.68)) and fair (IRA, 66.7% (95% CI, 66.6-66.7%); κ, 0.22 (95% CI, 0.12-0.37)), respectively.

CONCLUSIONS

MRI has excellent interobserver agreement in detecting the presence and depth of placental invasion, while agreement between the examiners is lower when assessing the topography of invasion. The findings of this study highlight the need for a standardized MRI staging system for PAS disorders, in order to facilitate objective correlation between prenatal imaging, pregnancy outcome and surgical management of these patients. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Prenatal ultrasound staging system for placenta accreta spectrum disorders

OBJECTIVES

To develop a prenatal ultrasound staging system for placenta accreta spectrum (PAS) disorders in women with placenta previa and to evaluate its association with surgical outcome, placental invasion and the clinical staging system for PAS disorders proposed by the International Federation of Gynecology and Obstetrics (FIGO).

METHODS

This was a secondary retrospective analysis of prospectively collected data from women with placenta previa. We classified women according to the following staging system for PAS disorders, based upon the presence of ultrasound signs of PAS in women with placenta previa: PAS0, placenta previa with no ultrasound signs of invasion or with placental lacunae but no evidence of abnormal uterus-bladder interface; PAS1, presence of at least two of placental lacunae, loss of the clear zone or bladder wall interruption; PAS2, PAS1 plus uterovescical hypervascularity; PAS3, PAS1 or PAS2 plus evidence of increased vascularity in the inferior part of the lower uterine segment potentially extending into the parametrial region. We explored whether this ultrasound staging system correlates with surgical outcome (estimated blood loss (EBL, mL), units of packed red blood cells (PRBC), fresh frozen plasma (FFP) and platelets (PLT) transfused, operation time (min), surgical complications defined as the occurrence of any damage to the bladder, ureters or bowel, length of hospital stay (days) and admission to intensive care unit (ICU)) and depth of placental invasion. The correlation between the present ultrasound staging system and the clinical grading system proposed by FIGO was assessed. Prenatal and surgical management were not based on the proposed prenatal ultrasound staging system. Linear and multiple regression models were used.

RESULTS

Two-hundred and fifty-nine women were included in the analysis. Mean EBL was 516 ± 151 mL in women with PAS0, 609 ± 146 mL in those with PAS1, 950 ± 190 mL in those with PAS2 and 1323 ± 533 mL in those with PAS3, and increased significantly with increasing severity of PAS ultrasound stage. Mean units of PRBC transfused were 0.05 ± 0.21 in PAS0, 0.10 ± 0.45 in PAS1, 1.19 ± 1.11 in PAS2 and 4.48 ± 2.06 in PAS3, and increased significantly with PAS stage. Similarly, there was a progressive increase in the mean units of FFP transfused from PAS1 to PAS3 (0.0 ± 0.0 in PAS1, 0.25 ± 1.0 in PAS2 and 3.63 ± 2.67 in PAS3). Women presenting with PAS3 on ultrasound had significantly more units of PLT transfused (2.37 ± 2.40) compared with those with PAS0 (0.03 ± 0.18), PAS1 (0.0 ± 0.0) or PAS2 (0.0 ± 0.0). Mean operation time was longer in women with PAS3 (184 ± 32 min) compared with those with PAS1 (153 ± 38 min) or PAS2 (161 ± 28 min). Similarly, women with PAS3 had longer hospital stay (7.4 ± 2.1 days) compared with those with PAS0 (3.4 ± 0.6 days), PAS1 (6.4 ± 1.3 days) or PAS2 (5.9 ± 0.8 days). On linear regression analysis, after adjusting for all potential confounders, higher PAS stage was associated independently with a significant increase in EBL (314 (95% CI, 230-399) mL per one-stage increase; P < 0.001), units of PRBC transfused (1.74 (95% CI, 1.33-2.15) per one-stage increase; P < 0.001), units of FFP transfused (1.19 (95% CI, 0.61-1.77) per one-stage increase; P < 0.001), units of PLT transfused (1.03 (95% CI, 0.59-1.47) per one-stage increase; P < 0.001), operation time (38.8 (95% CI, 31.6-46.1) min per one-stage increase; P < 0.001) and length of hospital stay (0.83 (95% CI, 0.46-1.27) days per one-stage increase; P < 0.001). On logistic regression analysis, increased severity of PAS was associated independently with surgical complications (odds ratio, 3.14 (95% CI, 1.36-7.25); P = 0.007), while only PAS3 was associated with admission to the ICU (P < 0.001). All women with PAS0 on ultrasound were classified as having Grade-1 PAS disorder according to the FIGO grading system. Conversely, of the women presenting with PAS1 on ultrasound, 64.1% (95% CI, 48.4-77.3%) were classified as having Grade-3, while 35.9% (95% CI, 22.7-51.6%) were classified as having Grade-4 PAS disorder, according to the FIGO grading system. All women with PAS2 were categorized as having Grade-5 and all those with PAS3 as having Grade-6 PAS disorder according to the FIGO system.

CONCLUSION

Ultrasound staging of PAS disorders is feasible and correlates with surgical outcome, depth of invasion and the FIGO clinical grading system. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

The clinical outcome of cesarean scar pregnancies implanted "on the scar" versus "in the niche"

BACKGROUND

The term cesarean scar pregnancy refers to placental implantation within the scar of a previous cesarean delivery. The rising numbers of cesarean deliveries in the last decades have led to an increased incidence of cesarean scar pregnancy. Complications of cesarean scar pregnancy include morbidly adherent placenta, uterine rupture, severe hemorrhage, and preterm labor. It is suspected that cesarean scar pregnancies that are implanted within a dehiscent scar ("niche") behave differently compared with those implanted on top of a well-healed scar. To date there are no studies that have compared pregnancy outcomes between cesarean scar pregnancies implanted either "on the scar" or "in the niche."

OBJECTIVES

The purpose of this study was to determine the pregnancy outcome of cesarean scar pregnancy implanted either "on the scar" or "in the niche."

STUDY DESIGN

This was a retrospective 2-center study of 17 patients with cesarean scar pregnancy that was diagnosed from 5-9 weeks gestation (median, 8 weeks). All cesarean scar pregnancies were categorized as either implanted or "on the scar" (group A) or "in the niche" (group B), based on their first-trimester transvaginal ultrasound examination. Clinical outcomes based on gestational age at delivery, mode of delivery, blood loss at delivery, neonate weight and placental histopathologic condition were compared between the groups with the use of the Mann-Whitney U test. Myometrial thickness overlying the placenta was compared among all the patients who required hysterectomy and those who did not with the use of the Mann-Whitney U test. Myometrial thickness was also correlated with gestational age at delivery with the use of Spearman's correlation.

RESULTS

Group A consisted of 6 patients; group B consisted of 11 patients. Gestational age at delivery was lower in group B (median, 34 weeks; range, 20-36 weeks) than in group A (median, 38 weeks; range, 37-39 weeks; P=.001). In group A, 5 patients were delivered via cesarean delivery (with normal placenta), and 1 patient underwent a cesarean-hysterectomy for placenta accreta. In group B, 10 patients had a cesarean-hysterectomy for placenta increta/percreta, and 1 patient underwent gravid-hysterectomy for vaginal bleeding at 20 weeks gestation. Blood loss was increased, but not significantly higher in group B (median, 1200 mL; range, 600-4000 mL) than in group A (median, 700 mL; range, 600-1400 mL; P=.117). Myometrium was statistically significantly thinner in the patients group that require hysterectomy (median, 1 mm; range, 0-2 mm) than in the group that did not (median, 5 mm; range, 4-9 mm; P=.001). Myometrial thickness showed a positive correlation with the gestational age (r=0.820; P<.0005).

CONCLUSION

Patients with cesarean scar pregnancy implanted "on the scar" had a substantially better outcome compared with patients in whom the cesarean scar pregnancy implanted "in the niche." Myometrial thickness <2 mm in the first-trimester ultrasound examination is associated with morbidly adherent placenta at delivery.

Selective Reduction Using Intravascular Potassium Chloride Injection after Laser Surgery for Twin-Twin Transfusion Syndrome

Selective reduction (SR) via intravascular potassium chloride (KCl) injection is contraindicated in monochorionic twins due to the presence of placental vascular communications, which may serve as a conduit for inter-twin passage of KCl or allow exsanguination of the living twin into the demised twin. After successful selective laser photocoagulation of communicating vessels (SLPCV) for twin-twin transfusion syndrome (TTTS), the twins' circulatory systems are rendered independent. Theoretically, intravascular KCl injection into one twin after successful SLPCV should not result in passage of the feticidal agent nor cause hemodynamic alterations in the co-twin. We describe 3 cases of 1,069 patients (0.3%) that underwent SLPCV for TTTS between 2003 and 2013 and subsequent SR. SLPCV was successfully completed at 180, 226, and 230 weeks' gestational age for Quintero stages III, IV, and III TTTS, respectively. SR via intravascular KCl injection was later performed at maternal request due to the risk of neurological compromise in one twin at 226, 254, and 236 weeks' gestational age. All co-twins survived after SR, and no neurological sequelae were suspected after birth. Further study is necessary before SR can be routinely considered after laser surgery for TTTS.

The contribution of birth defects to preterm birth and low birth weight

OBJECTIVE

To assess the impact of birth defects on preterm birth and low birth weight.

METHODS

Data from a large, prospective multi-center trial, the First and Second Trimester Evaluation of Risk (FASTER) Trial, were examined. All live births at more than 24 weeks of gestation with data on outcome and confounders were divided into two comparison groups: 1) those with a chromosomal or structural abnormality (birth defect) and 2) those with no abnormality detected in chromosomes or anatomy. Propensity scores were used to balance the groups, account for confounding, and reduce the bias of a large number of potential confounding factors in the assessment of the impact of a birth defect on outcome. Multiple logistic regression analysis was applied.

RESULTS

A singleton liveborn infant with a birth defect was 2.7 times more likely to be delivered preterm before 37 weeks of gestation (95% confidence interval [CI] 2.3-3.2), 7.0 times more likely to be delivered preterm before 34 weeks (95% CI 5.5-8.9), and 11.5 times more likely to be delivered very preterm before 32 weeks (95% CI 8.7-15.2). A singleton liveborn with a birth defect was 3.6 times more likely to have low birth weight at less than 2,500 g (95% CI 3.0-4.3) and 11.3 times more likely to be very low birth weight at less than 1,500 g (95% CI 8.5-15.1).

CONCLUSION

Birth defects are associated with preterm birth and low birth weight after controlling for multiple confounding factors, including shared risk factors and pregnancy complications, using propensity scoring adjustment in multivariable regression analysis. The independent effects of risk factors on perinatal outcomes such as preterm birth and low birth weight, usually complicated by numerous confounding factors, may benefit from the application of this methodology, which can be used to minimize bias and account for confounding. Furthermore, this suggests that clinical and public health interventions aimed at preventing birth defects may have added benefits in preventing preterm birth and low birth weight.

LEVEL OF EVIDENCE

II.

Early Access to Prenatal Care

OBJECTIVE

To investigate racial disparities in perinatal mortality in women with early access to prenatal care.

METHODS

A prospectively collected database from a large, multicenter investigation of singleton pregnancies, the FASTER trial, was queried. Patients were recruited from an unselected obstetric population between 1999 and 2002. A total of 35,529 pregnancies with early access to prenatal care were reviewed for this analysis. The timing of perinatal loss was assessed. The following intervals were evaluated: fetal demise at less than 24 weeks of gestation, fetal demise at 24 or more weeks of gestation, and neonatal demise. Perinatal mortality was defined as the sum of these three intervals.

RESULTS

The study population was 5% black, 22% Hispanic, 68% white, and 5% other. All minority races experienced higher rates of intrauterine growth restriction, preeclampsia, preterm premature rupture of membranes, gestational diabetes, placenta previa, preterm birth, very-preterm birth, cesarean delivery, light vaginal bleeding, and heavy vaginal bleeding compared with the white population. Overall perinatal mortality was 13 per 1,000 (471/35,529). The adjusted odds ratios (95% confidence intervals) for perinatal mortality (utilizing the white population as the referent race) were: black 3.5 (2.5-4.9), Hispanic 1.5 (1.2-2.1), and other 1.9 (1.3-2.8).

CONCLUSION

Racial disparities in perinatal mortality persist in contemporary obstetric practice despite early access to prenatal care.

LEVEL OF EVIDENCE

II-2.

Endoscopic closure of fetal membrane defects: comparing iatrogenic versus spontaneous rupture cases

OBJECTIVE

Currently, physicians manage preterm premature rupture of membranes (PPROM) by expectant management or termination of the gestation. A therapy aimed at sealing membranes would be optimal to maintain the pregnancy and achieve a normal neonate. Our objective was to compare an endoscopic technique for intrauterine closure of fetal membrane defects after both iatrogenic and spontaneous rupture of membranes.

METHODS

Our technique was performed on four patients experiencing PPROM spontaneously and four patients after genetic amniocentesis. Intrauterine endoscopy allowed direct visualization of membrane defects. Rapid sequential injections of platelets, fibrin glue and powdered collagen slurry were administered at the site of the defect and of trocar placement. Sonography for amniotic fluid index, nitrazine and fern testing and pad count were performed after each procedure at three intervals: immediately post-procedure, and after 24 and 48 h.

RESULTS

Eight patients underwent endoscopic intrauterine sealing of ruptured membranes between 16 and 24 weeks of gestation: four were spontaneous ruptures and four were ruptures post-amniocentesis. In the post-amniocentesis group, three patients delivered viable infants at 26, 32 and 34 weeks. In one patient, the membranes ruptured again 12 h after the sealing procedure and she decided to undergo termination of pregnancy. Of the four spontaneous rupture patients, two experienced preterm labor and delivery within 2 days of the procedure. One patient was diagnosed with fetal demise 12 h post-procedure, and one patient delivered a neonate at 31 weeks of gestation with severe respiratory distress syndrome.

CONCLUSIONS

This technique for sealing ruptured membranes is effective after amniocentesis, but may not be of benefit with spontaneous rupture.

The role of ultrasound evaluation in the detection of early-stage epithelial ovarian cancer

OBJECTIVE

Epithelial ovarian cancer kills more women than all other gynecologic malignancies combined because of our inability to detect early-stage disease. Ultrasonography has demonstrated usefulness in the detection of ovarian cancer in asymptomatic women, but its value for the detection of early-stage epithelial ovarian cancer in women of increased risk is uncertain. We examined the usefulness of sonography in the detection of early-stage epithelial ovarian cancer in asymptomatic high-risk women who participated in the National Ovarian Cancer Early Detection Program.

STUDY DESIGN

Only asymptomatic women of increased risk for the development of ovarian cancer with initial normal gynecologic and ultrasound examinations were eligible to participate in the institutional review board-approved National Ovarian Cancer Early Detection Program. Participants underwent comprehensive gynecologic and ultrasound examinations every 6 months. Increased risk includes women with at least 1 affected first-degree relative with ovarian cancer; a personal history of breast, ovarian, or colon cancer; > or =1 affected first- and second-degree relatives with breast and or ovarian cancer; inheritance of a breast cancer mutation from an affected family member, or membership within a recognized cancer syndrome.

RESULTS

The average age of the 4526 women who were evaluated was 46 years; 2610 women were premenopausal, and 1916 women were postmenopausal. A total of 12,709 scans have been performed since 1990. Visualization of both ovaries was noted in 98% of premenopausal and in 94% of postmenopausal women. Fourteen women had undergone unilateral salpingo-oophorectomy. Recall rates at less than the routine 6-month interval were 0.4% in the premenopausal and 0.3% in postmenopausal women. A total of 98 women with persistent adnexal masses were identified, and 49 invasive surgical procedures were performed that diagnosed 37 benign ovarian tumors and 12 gynecologic malignancies. All cancers were detected in asymptomatic women who had normal ultrasound and physical examinations 12 and 6 months before the cancer diagnosis. The detected malignancies were fallopian tube carcinoma (stage IIIC; n = 4 women), primary peritoneal carcinoma (n = 4 women; stage IIIA, 1 woman; stage IIIB, 2 women; stage IIIC, 1 woman), epithelial ovarian cancer (stages IIIA and IIIB; n = 2 women), and endometrial adenocarcinoma (stage IA; n = 2 women). Additionally 37 primary and 12 recurrent breast carcinomas were detected by physical examination. A total of 184 women with genetic predisposition (breast cancer positive) have undergone a prophylactic bilateral salpingo-oophorectomy; 23% of these procedures found atypical hyperplasia, and unexpectedly, 2 women (1%) were found to have stage III (A and B) primary peritoneal carcinoma.

CONCLUSION

This study demonstrates the limited value of diagnostic ultrasound examination as an independent modality for the detection of early-stage epithelial ovarian cancer in asymptomatic women who are at increased risk for disease.

The closure of iatrogenic membrane defects after amniocentesis and endoscopic intrauterine procedures

OBJECTIVE

To describe a new technique for wound closure after endoscopic intrauterine procedures which prevents amniotic fluid leakage after the procedure.

STUDY DESIGN

This is an observational study which reviews a new technique under an IRB-approved protocol. The rationale for this study was the increasing frequency of intrauterine endoscopic procedures. The most common complication of these procedures is persistent leakage of amniotic fluid from puncture sites, which can result in preterm labor and preterm delivery. Thus, these procedures carry a high morbidity rate that may overcome the benefit of the intervention. We have employed a new technique, which has successfully prevented amniotic fluid leakage following the procedure. The instruments used for the endoscopic procedures were no larger than 3.5 mm for all cases. A sealant of platelets was rapidly injected followed by injection of fibrin glue and powdered collagen slurry at each puncture site. Sonography for modified AFI, clinical examination for nitrazine and ferning, and pad count were performed after each procedure at three intervals: immediately after the procedure, 24 h and 48 h.

RESULTS

Eight patients undergoing an endoscopic intrauterine procedure (either cord ligation for twin-twin transfusion syndrome or sealing of ruptured membranes after amniocentesis) were included. All patients were treated between 18 and 24 weeks of gestation. Sonography, clinical examination and pad count revealed no evidence of amniotic fluid leakage either intra-abdominally or vaginally in any of the patients. There was 1 patient who ruptured membranes 12 h after the procedure due to severe vomiting. Another patient elected to terminate the pregnancy 48 h after the procedure without evidence of leakage. The remaining patients continued for 8 weeks or more without fluid leakage.

CONCLUSION

The technique described, immediate sealing of puncture wounds following endoscopic intrauterine procedures, is effective in preventing amniotic fluid loss after the procedure.

Three-dimensional ultrasound to differentiate epigastric heteropagus conjoined twins from a TRAP sequence

Twin reversed arterial perfusion sequence and epigastric heteropagus conjoined twins may appear similar antenatally. Three-dimensional ultrasound evaluated the relationship of a completely formed fetus and an adjacent second body consisting of a pelvis with 2 lower extremities, confirming the final diagnosis when two-dimensional ultrasound was unsuccessful. Three-dimensional ultrasound is useful in diagnosing epigastric heteropagus conjoined twins.

First-trimester diagnosis of sacrococcygeal teratoma: the role of three-dimensional ultrasound

A fetus was suspected of having a sacrococcygeal teratoma (SCT) on routine nuchal translucency evaluation by sonography at 12+3 weeks. The patient was referred for three-dimensional (3D) sonography to further delineate the extent of the mass. In this case, real-time scanning of the mass in 3D mode assisted the diagnosis of the mass and patient counseling. We present what we believe to be the first case of SCT imaged in the first trimester using 3D ultrasound.

Evaluation of endometrial polyps

OBJECTIVE

Endometrial polyps are relatively common in all groups of women. More polyps are being diagnosed with the widespread use of transvaginal ultrasound scanning and sonohysterography. The reported incidence of malignancy is low. The potential benefit of a noninvasive technique to distinguish benign from malignant polyps is obvious. This study was undertaken to evaluate endometrial polyps by color flow Doppler ultrasound scanning and histopathologic examination.

STUDY DESIGN

This was an observational study of patients with an endometrial polyp on sonohysterography who underwent interrogation of their polyp with color Doppler ultrasound scanning and subsequently polypectomy. Polyp volume, resistive index, pulsatility index, indication for scan (bleeding vs incidental), and patient age were correlated with histopathologic type of the polyp (nonfunctional, proliferative, secretory, hyperplastic, or malignant).

RESULTS

Of 61 patients studied, 42 patients (68.9%) were scanned for abnormal bleeding, and 19 patients (31.1%) had their polyps discovered incidentally. There were no statistically significant differences between histologic categories and the resistive index, pulsatility index, or size of the polyp. The age of patients with nonfunctional polyps was significantly greater than any other group (P <.001). Ninety-four percent of the functional polyps were discovered because of abnormal bleeding; 38% of the nonfunctional polyps were discovered incidentally (P <.001).

CONCLUSION

The data suggest that the objective assessment of blood flow impedance (resistive index, pulsatility index) in endometrial polyps and the size of these polyps cannot replace surgical removal and pathologic evaluation to predict histologic type. Patients with nonfunctional polyps were older and less likely to have vaginal bleeding.

Real-time spectral analysis of the fetal EEG: a new approach to monitoring sleep states and fetal condition during labor

Adverse perinatal events affecting cerebral functions are a major cause of neonatal mortality, morbidity, and long-term neurologic deficit. Intrapartum fetal EEG, which records fetal brain electrical activity, provides a monitoring modality for evaluating the fetal CNS during labor. In this study, we describe a new approach to such monitoring that is based on real-time spectral analysis of the fetal EEG during labor. Fourteen pregnant women with uncomplicated term pregnancies who went into labor participated in the study. Two suction-cup electrodes were applied to the fetal scalp at the occipitoparietal or parietal region after rupture of membranes. Real-time spectral analysis was used to determine the frequency and amplitude of the fetal EEG signal. The spectral edge frequency (SEF) was calculated as the frequency below which 90% of the power in the power spectrum resides. The average EEG amplitude and the SEF were displayed using the density spectral array technique. Fetal heart rate and intrauterine pressure were also measured. Two fundamental EEG patterns were identified: high-voltage slow activity and low-voltage fast activity. The SEF was found to be an excellent index of cyclic EEG activity. Fetal heart rate demonstrated increased variability and an elevated baseline during low-voltage fast activity, whereas both parameters decreased during high-voltage slow activity. During episodes of variable decelerations in the fetal heart rate, a decrease in the SEF was observed, accompanied by an increased EEG voltage. The results obtained substantiate the presence of sleep cycles in the human fetus. This kind of cortical activity monitoring may enable rapid alertness to cerebral hypoxia and allow for prompt intervention, thereby decreasing the risk for birth asphyxia and subsequent brain damage.

Accurate diagnosis of postabortal placental remnant by sonohysterography and color Doppler sonographic studies

The decision whether to perform uterine curettage for postabortal bleeding depends on the ability to demonstrate placental remnants in the uterine cavity. However, diagnosis of postabortal trophoblastic residua by conventional ultrasonography may be inconclusive. We report our experience with the use of combined sonohysterography and color Doppler to demonstrate a placental polyp after early pregnancy termination.

Heterotopic pregnancy after ovulation induction and assisted reproductive technologies: a literature review from 1971 to 1993

OBJECTIVE

To review and analyze records on heterotopic pregnancy occurring after ovulation induction and assisted reproductive technologies.

DATA IDENTIFICATION

Case reports in the English literature related to the topic were identified through a computerized bibliography search up to December 1993.

CONCLUSIONS

The incidence of heterotopic pregnancies increased in recent years because of the escalating use of new reproductive technologies in infertile patients and has stabilized at approximately 1:100 pregnancies with these procedures. The main reasons for development of such a condition in these patients are past tubal or pelvic disease and multiple ovulations or multiple ET. Progress has been made in diagnosis of heterotopic pregnancy during the last two decades, mainly because of development of ultrasonographic techniques, especially transvaginal ultrasonography. Treatment of heterotopic pregnancy should be prompt to avoid maternal morbidity and mortality from extensive intraperitoneal bleeding. No increased intrauterine fetal mortality due to hemoperitoneum has been proven in the present review, except in advanced cornual pregnancies. More experience is needed for application of new treatment modalities such as salpingocentesis, which are used successfully for ectopic pregnancy, in treatment of heterotopic pregnancy. With early diagnosis and skillful treatment, the outcome of the intrauterine pregnancy is favorable and its survival rate should increase in the future.

Age and the ovarian follicle pool assessed with transvaginal ultrasonography

OBJECTIVE

We tested whether transvaginal ultrasonography could detect the age-related decrease in follicle counts that has been observed in autopsy studies.

STUDY DESIGN

Thirty-one healthy volunteers in three age groups (22 to 25, 30 to 33, and 39 to 42 years) underwent ultrasonography in the follicular and luteal phases of the menstrual cycle. At the conclusion of the study the 124 ovarian scans were randomly ordered and antral follicles > or = 2 mm were counted by an evaluator unaware of age. Ordinary least-squares linear regression was used to estimate the associations of age with the total antral follicle count and with ln (1 + follicle count).

RESULTS

The numbers of antral follicles > or = 2 mm decreased by about 60% between 22 and 42 years. Age-related decreases were similar for both phases of the cycle and held for both smaller (2 to 3.5 mm) and larger (>3.5 mm) follicles.

CONCLUSION

We hypothesize that ultrasonographically derived counts of follicles provide a measure of reproductive age that may help to predict age-related phenomena.

International, collaborative experience of 1789 patients having multifetal pregnancy reduction: a plateauing of risks and outcomes

OBJECTIVE

To develop the most up-to-date, complete data base of multifetal pregnancy reduction (MFPR) from cases, and to provide the best counseling for couples with multifetal pregnancies.

METHODS

From nine centers in five countries, 1789 completed MFPR cases were collected and outcomes evaluated. Pregnancy losses were defined as through 24 weeks and deliveries categorized in groups of 25-28, 29-32, 33-36, and 37 or more weeks.

RESULTS

Overall, the pregnancy loss rate was 11.7% but varied from a low of 7.6% for triplets to twins and increased with each additional starting number to 22.9% for sextuplets or higher. Early premature deliveries (25-28 weeks) were 4.5% and varied with starting number. Loss rates by finishing number were highest for triplets and lowest for twins, but gestational age at delivery was highest for singletons.

CONCLUSIONS

Multifetal pregnancy reduction has been shown to be a safe and effective method to improve outcome in multifetal pregnancies. Outcomes are worse with higher-order gestations and support the need for continued vigilance of fertility therapy.

The psychological effects of multifetal pregnancy reduction

OBJECTIVE

To study the psychological effects of multifetal pregnancy reduction.

DESIGN AND SETTING

Hour-long semistructured telephone interviews with both multifetal pregnancy reduction patients and control subjects.

PATIENTS

Forty-two multifetal pregnancy reduction patients were contacted within 1 year of undergoing the procedure. Forty-four control subjects had become pregnant after infertility evaluation or treatment but conceived only a single fetus or twins and thus did not consider fetal termination.

MAIN OUTCOME MEASURES

Standardized measures of depressive disorder and current psychiatric symptoms, as well as questions about emotional reactions to multifetal pregnancy reduction.

RESULTS

Reduction patients who were pregnant or postpartum at the time of the interview (n = 34) were no more likely than pregnant or postpartum controls (n = 34) to report episodes of depression or high psychiatric symptom levels. The same proportion (14.7%) of both reduction patients and controls with a successful pregnancy outcome met criteria for an episode of major depressive disorder occurring during the 9 months before the interview. In contrast, the 8 reduction patients who spontaneously aborted the entire pregnancy and the 10 controls who spontaneously aborted reported significantly higher rates of the full depressive syndrome.

CONCLUSIONS

Multifetal pregnancy reduction is experienced as stressful and distressing. However, when pregnancy outcome is successful, the medical intervention does not put women at significant risk for affective illness or elevated levels of psychiatric symptoms.

Transvaginal ultrasonographic evaluation of the cervix before labor: presence of cervical wedging is associated with shorter duration of induced labor

OBJECTIVE

Our purpose was to test the hypothesis that transvaginal ultrasonographically determined characteristics of the cervix are associated with duration of induced labor.

STUDY DESIGN

Fifty-three patients scheduled for induction of labor underwent transvaginal ultrasonography and digital cervical examinations before labor induction. Cox proportional-hazards multiple regression analysis was performed to determine the variables that made a significant contribution to the prediction of latent-phase and total labor duration. In the analysis the possible confounding effects of exogenous prostaglandin, previous vaginal delivery, and previous termination of pregnancy were controlled.

RESULTS

Latent-phase and total labor duration were significantly associated with the presence of cervical wedging noted on transvaginal ultrasonography and administration of prostaglandin but not with the result of digital examination of cervical effacement or dilatation. Latent-phase duration was also associated with cervical length measured by transvaginal ultrasonography. The presence of wedging was significantly associated with shorter latent (15.9 +/- 1.7 vs 34.1 +/- 3.8 hours, p = 0.0001) and total (22.0 +/- 1.8 vs 38.3 +/- 3.6 hours, p = 0.0001) labor length.

CONCLUSION

The presence of wedging and decreased cervical length observed by transvaginal ultrasonography is associated with a shorter duration of induced labor and may be useful in the evaluation of induction candidates.

Transabdominal versus transcervical and transvaginal multifetal pregnancy reduction: international collaborative experience of more than one thousand cases

OBJECTIVES

Two major approaches for multifetal pregnancy reduction have been developed over the past several years: transabdominal potassium chloride by injection and pelvic procedures by either transcervical aspiration or transvaginal potassium chloride injection or by an automated spring-loaded puncture device. The purpose of this study was to create the largest database from among the world's largest centers to assess possible differences in efficacy and complication rates by transabdominal or transcervical or multifetal pregnancy reduction.

STUDY DESIGN

Data on over 1000 completed pregnancies that underwent multifetal pregnancy reduction by both methods from major centers with among the highest worldwide experience were combined. Transabdominal cases were divided temporally (1986 through 1991 and 1991 through 1993).

RESULTS

Transabdominal multifetal pregnancy reduction was successfully performed on 846 patients and transcervical or transvaginal on 238 patients. Transcervical or transvaginal reduction is performed earlier and starts and finishes with fewer embryos. In 12.6% of cases transcervical or transvaginal reduction left a singleton as opposed to 4.4% for transabdominal reduction. Pregnancy losses (up to 24 weeks) were observed in 13.1% of transcervical or transvaginal cases and in 16.2% of transabdominal cases early in the series and 8.8% of late transabdominal cases. Transcervical or transvaginal reduction may be safer very early in gestation and transabdominal safer later in the first trimester. Premature deliveries were comparable, with only about 5% delivered between 25 and 28 weeks. The smaller starting numbers for transcervical and transvaginal reduction may explain a slightly higher term delivery rate. The transabdominal route tends to reduce the fundal embryos and the transcervical and transvaginal the lower ones. The significance of this is not clear.

CONCLUSIONS

(1) Multifetal pregnancy reduction by either method is a relatively safe and efficient method for improving outcome in multifetal pregnancies. (2) More than 84% are delivered at > 33 weeks. (3) The experience and preference of the operator are probably the key determinants for an individual patient. (4) An inverse relationship of starting and finishing number to loss rates and gestational age at delivery suggests that there still is a cost of iatrogenic multifetal pregnancies, even if multifetal pregnancy reduction can be successfully performed.

First-trimester fetal biometry using transvaginal sonography

First-trimester fetal biometry using transvaginal sonography is now feasible and desirable due to improved imaging and probe maneuverability. A study of 144 early normal pregnancies with precise dates is presented. Regression models were constructed for the crown-rump length, biparietal diameter, head circumference and abdominal circumference. Error analysis of the technique and calculations was performed. First-trimester fetal biometry may be used for obtaining precise estimates of gestational age and may help to detect early fetal maldevelopment resulting in abnormal growth.

Emergency room use of transvaginal ultrasonography by obstetrics and gynecology residents

OBJECTIVE

The objective of this study was to evaluate the feasibility and diagnostic value of the emergency room use of transvaginal ultrasonography operated by the obstetrics and gynecology residents.

STUDY DESIGN

One hundred sixty-eight patients scanned in the emergency room constituted the study group and were compared with 61 patients for whom emergency room scanning was not available. Scanning and no-scanning days alternated for a 6-month period. The Student t test was used in the analysis.

RESULTS

By comparing the two patient groups a statistically significant (p less than 0.0001) difference was seen in the time spent by the group of patients scanned in the emergency room (40 minutes) when compared with that of the patients for whom no emergency room scanning was available (215 minutes). The residents expressed high confidence in the scanning procedure. There were six misdiagnosed cases, three of them nonruptured ectopic gestations. However, none of these patients was discharged without adequate treatment.

CONCLUSION

The study confirmed our hypothesis that obstetrics and gynecology residents can operate and should have available ultrasonography machines in the emergency departments to render quicker and better patient care.

Changes in uterine blood flow during human pregnancy

A transvaginal duplex Doppler ultrasonography system was used to measure blood flow characteristics in the ascending uterine artery before and during pregnancy. The system uses a 5 MHz Doppler transducer coupled to a 6.5 MHz imaging probe. There was a steady increase in volume flow rate in the left ascending uterine artery from a mean of 94.5 ml/min before pregnancy to a mean of 342 ml/min in late gestation (reflecting a 3.5-fold increase). With the assumption of equal flow on both uterine arteries, the fraction of the cardiac output that is distributed to these vessels was calculated to be 3.5% in early pregnancy and to reach 12% near term. The mean diameter of this vessel in the nonpregnant state was 1.6 mm, increasing to 3.7 mm toward term. The resistance to flow, expressed as the peak systolic to end-diastolic flow velocity ratio, declined from a mean of 5.3 in the nonpregnant state to a mean of 2.3 near term. These changes reflect the perpetual growth and development of the uteroplacental circulation, which provides the metabolic demands of the growing fetus throughout gestation.

Dating the early pregnancy by sequential appearance of embryonic structures

A total of 97 transvaginal scans were performed from 4 to 12 weeks' gestation in normal and accurately dated gestations. The sequential appearance of six structures were examined: (1) the gestational sac only was present during week 4; (2) the yolk sac appeared in week 5; (3) the fetal pole with detectable heart motion was first seen in week 6; (4) the single unpartitioned ventricle in the brain marked week 7; (5) the falx cerebri appeared during week 9; and (6) the appearance and the disappearance of the physiologic midgut herniation were seen in week 8 and week 11, respectively. Inasmuch as the time in gestation at which these structures appear characterizes the gestational age more than any measurement at this age, we propose a practical method to determine the correct gestational age in early first-trimester pregnancy.

Transvaginal salpingocentesis: a new technique for treating ectopic pregnancy

Transvaginal sonography is an important tool for diagnosing ectopic pregnancy. In this report the transvaginal passage of a needle, with sonographic guidance, into a tubal gestational sac with a live fetus is demonstrated. We injected potassium chloride solution to arrest cardiac activity, terminating the ectopic pregnancy without surgical intervention. The new therapeutic use of transvaginal sonography is an important addition to the treatment of this prevalent disease.