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Obstetrics and Gynecology Sep 2023Vasa previa refers to unprotected fetal vessels running through the membranes over the cervix. Until recently, this condition was associated with an exceedingly high...
Vasa previa refers to unprotected fetal vessels running through the membranes over the cervix. Until recently, this condition was associated with an exceedingly high perinatal mortality rate attributable to fetal exsanguination when the membranes ruptured. However, ultrasonography has made it possible to diagnose the condition prenatally, allowing cesarean delivery before labor or rupture of the membranes. Several recent studies have indicated excellent outcomes with prenatally diagnosed vasa previa. However, outcomes continue to be dismal when vasa previa is undiagnosed before labor. Risk factors for vasa previa include second-trimester placenta previa and low-lying placentas, velamentous cord insertion, placentas with accessory lobes, in vitro fertilization, and multifetal gestations. Recognition of individuals who are at risk and screening them will greatly decrease the mortality rate from this condition. Because of the relative rarity of vasa previa, there are no randomized controlled trials to guide management. Therefore, recommendations on the diagnosis and management of vasa previa are based largely on cohort studies and expert opinion. This Clinical Expert Series review addresses the epidemiology, pathophysiology, natural history, diagnosis and management of vasa previa, as well as innovative treatments for the condition.
Topics: Female; Pregnancy; Humans; Vasa Previa; Cesarean Section; Fertilization in Vitro; Fetus; Labor, Obstetric
PubMed: 37590981
DOI: 10.1097/AOG.0000000000005287 -
Journal of Obstetrics and Gynaecology... Jul 2023To summarize the current evidence and to make recommendations for diagnosis and classification of vasa previa and for management of women with this diagnosis.
OBJECTIVE
To summarize the current evidence and to make recommendations for diagnosis and classification of vasa previa and for management of women with this diagnosis.
TARGET POPULATION
Pregnant women with vasa previa or low-lying fetal vessels.
OPTIONS
To manage vasa previa in hospital or at home, and to perform a cesarean delivery preterm or at term, or to allow a trial of labour when a diagnosis of vasa previa or low-lying fetal vessels is suspected or confirmed.
OUTCOMES
Prolonged hospitalization, preterm birth, rate of cesarean delivery, and neonatal morbidity and mortality.
BENEFITS, HARMS, AND COSTS
Women with vasa previa or low-lying fetal vessels are at an increased risk of maternal and fetal or postnatal adverse outcomes. These outcomes include a potentially incorrect diagnosis, need for hospitalization, unnecessary restriction of activities, an early delivery, and an unnecessary cesarean delivery. Optimization of diagnostic and management protocols can improve maternal and fetal or postnatal outcomes.
EVIDENCE
Medline, Pubmed, Embase, and the Cochrane Library were searched from inception to March 2022, using medical subject headings (MeSH) and keywords related to pregnancy, vasa previa, low-lying fetal vessels, antepartum hemorrhage, short cervix, preterm labour, and cesarean delivery. This document presents an abstraction of the evidence rather than a methodological review.
VALIDATION METHODS
The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).
INTENDED AUDIENCE
Obstetric care providers, including obstetricians, family physicians, nurses, midwives, maternal-fetal medicine specialists, and radiologists.
TWEETABLE ABSTRACT
Unprotected fetal vessels in placental membranes and cord that are close to the cervix, including vasa previa, need careful characterization by sonographic examination and evidence-based management to reduce risks to the baby and the mother during pregnancy and delivery.
SUMMARY STATEMENTS
RECOMMENDATIONS.
Topics: Pregnancy; Female; Infant, Newborn; Humans; Vasa Previa; Placenta; Premature Birth; Prenatal Care; Fetus
PubMed: 37209787
DOI: 10.1016/j.jogc.2023.05.009 -
Best Practice & Research. Clinical... Aug 2023Screening for clinically significant placenta accreta spectrum (PAS) is possible with a high degree of accuracy (both sensitivity and specificity >90-95%). The group of... (Review)
Review
Screening for clinically significant placenta accreta spectrum (PAS) is possible with a high degree of accuracy (both sensitivity and specificity >90-95%). The group of women to focus on are those with placenta previa and one or more prior Cesarean deliveries. Screening for PAS not associated with placenta previa is not as productive, and several false negatives have been described. The results of the screening program indicate that women have a low or high probability of PAS. Screen-positive women or those with uncertain ultrasound features should be referred to a center of excellence. Those confirmed to have a high probability of PAS should electively be delivered at such centers.
Topics: Pregnancy; Female; Humans; Placenta Accreta; Placenta Previa; Retrospective Studies; Cesarean Section; Ultrasonography; Placenta
PubMed: 37541113
DOI: 10.1016/j.bpobgyn.2023.102392 -
Seminars in Perinatology Feb 2024Stillbirth affects a large proportion of pregnancies world-wide annually and continues to be a major public health concern. Several causes of stillbirth have been...
Stillbirth affects a large proportion of pregnancies world-wide annually and continues to be a major public health concern. Several causes of stillbirth have been identified and include obstetrical complications, placental abnormalities, fetal malformations, infections, and medical complications in pregnancy. Placental abnormalities such as placental abruption, chorioangioma, vasa previa, and umbilical cord abnormalities have been identified as causes of death for a significant proportion of stillbirths. In the absence of placental abnormalities, the gross and histologic changes in the placenta in stillbirth are found when secondary to other etiologies. Here we describe both gross and histologic changes of the placenta that are associated with stillbirth.
Topics: Pregnancy; Female; Humans; Stillbirth; Placenta; Placenta Diseases; Abruptio Placentae; Public Health
PubMed: 38199875
DOI: 10.1016/j.semperi.2023.151871 -
Human Reproduction Update Sep 2023The number of frozen embryo transfers (FET) has increased dramatically over the past decade. Based on current evidence, there is no difference in pregnancy rates when... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The number of frozen embryo transfers (FET) has increased dramatically over the past decade. Based on current evidence, there is no difference in pregnancy rates when natural cycle FET (NC-FET) is compared to artificial cycle FET (AC-FET) in subfertile women. However, NC-FET seems to be associated with lower risk of adverse obstetric and neonatal outcomes compared with AC-FET cycles. Currently, there is no consensus about whether NC-FET needs to be combined with luteal phase support (LPS) or not. The question of how to prepare the endometrium for FET has now gained even more importance and taken the dimension of safety into account as it should not simply be reduced to the basic question of effectiveness.
OBJECTIVE AND RATIONALE
The objective of this project was to determine whether NC-FET, with or without LPS, decreases the risk of adverse obstetric and neonatal outcomes compared with AC-FET.
SEARCH METHODS
A systematic review and meta-analysis was carried out. A literature search was performed using the following databases: CINAHL, EMBASE, and MEDLINE from inception to 10 October 2022. Observational studies, including cohort studies, and registries comparing obstetric and neonatal outcomes between singleton pregnancies after NC-FET and those after AC-FET were sought. Risk of bias was assessed using the ROBINS-I tool. The quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach. We calculated pooled odds ratios (ORs), pooled risk differences (RDs), pooled adjusted ORs, and prevalence estimates with 95% CI using a random effect model, while heterogeneity was assessed by the I2.
OUTCOMES
The conducted search identified 2436 studies, 890 duplicates were removed and 1546 studies were screened. Thirty studies (NC-FET n = 56 445; AC-FET n = 57 231) were included, 19 of which used LPS in NC-FET. Birthweight was lower following NC-FET versus AC-FET (mean difference 26.35 g; 95% CI 11.61-41.08, I2 = 63%). Furthermore NC-FET compared to AC-FET resulted in a lower risk of large for gestational age (OR 0.88, 95% 0.83-0.94, I2 = 54%), macrosomia (OR 0.81; 95% CI 0.71-0.93, I2 = 68%), low birthweight (OR 0.81, 95% CI 0.77-0.85, I2 = 41%), early pregnancy loss (OR 0.73; 95% CI 0.61-0.86, I2 = 70%), preterm birth (OR 0.80; 95% CI 0.75-0.85, I2 = 20%), very preterm birth (OR 0.66, 95% CI 0.53-0.84, I2 = 0%), hypertensive disorders of pregnancy (OR 0.60, 95% CI 0.50-0.65, I2 = 61%), pre-eclampsia (OR 0.50; 95% CI 0.42-0.60, I2 = 44%), placenta previa (OR 0.84, 95% CI 0.73-0.97, I2 = 0%), and postpartum hemorrhage (OR 0.43; 95% CI 0.38-0.48, I2 = 53%). Stratified analyses on LPS use in NC-FET suggested that, compared to AC-FET, NC-FET with LPS decreased preterm birth risk, while NC-FET without LPS did not (OR 0.75, 95% CI 0.70-0.81). LPS use did not modify the other outcomes. Heterogeneity varied from low to high, while quality of the evidence was very low to moderate.
WIDER IMPLICATIONS
This study confirms that NC-FET decreases the risk of adverse obstetric and neonatal outcomes compared with AC-FET. We estimate that for each adverse outcome, use of NC-FET may prevent 4 to 22 cases per 1000 women. Consequently, NC-FET should be the preferred treatment in women with ovulatory cycles undergoing FET. Based on very low quality of evidence, the risk of preterm birth be decreased when LPS is used in NC-FET compared to AC-FET. However, because of many uncertainties-the major being the debate about efficacy of the use of LPS-future research is needed on efficacy and safety of LPS and no recommendation can be made about the use of LPS.
Topics: Pregnancy; Infant, Newborn; Female; Humans; Birth Weight; Premature Birth; Luteal Phase; Lipopolysaccharides; Cryopreservation; Embryo Transfer; Pregnancy Rate; Retrospective Studies
PubMed: 37172270
DOI: 10.1093/humupd/dmad011 -
American Journal of Obstetrics &... Aug 2023This systematic review and meta-analysis aimed to assess clinical characteristics related to pathologically proven placenta accreta spectrum without placenta previa. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
This systematic review and meta-analysis aimed to assess clinical characteristics related to pathologically proven placenta accreta spectrum without placenta previa.
DATA SOURCES
A literature search of PubMed, the Cochrane database, and Web of Science was performed from inception to September 7, 2022.
STUDY ELIGIBILITY CRITERIA
The primary outcomes were invasive placenta (including increta or percreta), blood loss, hysterectomy, and antenatal diagnosis. In addition, maternal age, assisted reproductive technology, previous cesarean delivery, and previous uterine procedures were investigated as potential risk factors. The inclusion criteria were studies evaluating the clinical presentation of pathologically diagnosed PAS without placenta previa.
METHODS
Study screening was conducted after duplicates were identified and removed. The quality of each study and the publication bias were assessed. Forest plots and I statistics were calculated for each study outcome for each group. The main analysis was a random-effects analysis.
RESULTS
Among 2598 studies that were initially retrieved, 5 were included in the review. With the exception of 1 study, 4 studies were included in the meta-analysis. This meta-analysis showed that placenta accreta spectrum without placenta previa was associated with less risk of invasive placenta (odds ratio, 0.24; 95% confidence interval, 0.16-0.37), blood loss (mean difference, -1.19; 95% confidence interval, -2.09 to -0.28) and hysterectomy (odds ratio, 0.11; 95% confidence interval, 0.02-0.53), and more difficult to diagnose prenatally (odds ratio, 0.13; 95% confidence interval, 0.04-0.45) than placenta accreta spectrum with placenta previa. In addition, assisted reproductive technology and a previous uterine procedure were strong risk factors for placenta accreta spectrum without placenta previa, whhereas previous cesarean delivery was a strong risk factor for placenta accreta spectrum with placenta previa.
CONCLUSION
The differences in clinical aspects of placenta accreta spectrum with and without placenta previa need to be understood.
Topics: Pregnancy; Female; Humans; Placenta Accreta; Retrospective Studies; Placenta Previa; Hysterectomy; Risk Factors
PubMed: 37211089
DOI: 10.1016/j.ajogmf.2023.101027 -
Cureus May 2024Placenta previa poses significant risks to maternal and perinatal health, yet its management remains challenging. This comprehensive review synthesizes current evidence... (Review)
Review
Placenta previa poses significant risks to maternal and perinatal health, yet its management remains challenging. This comprehensive review synthesizes current evidence on maternal and perinatal outcomes in placenta previa, addressing its epidemiology, pathophysiology, diagnosis, and management strategies. Placenta previa complicates pregnancies, with increasing incidence linked to factors such as advanced maternal age and rising cesarean rates. Maternal complications, including hemorrhage and placenta accreta spectrum disorders, pose substantial risks. At the same time, perinatal outcomes are marked by increased rates of preterm birth, intrauterine growth restriction, and neonatal morbidity and mortality. Timely diagnosis and appropriate management, including antenatal corticosteroids and multidisciplinary care, are critical for optimizing outcomes. Future research should focus on improving diagnostic methods, evaluating novel interventions, and assessing long-term neurodevelopmental outcomes. This review underscores the importance of informed clinical practice and ongoing research efforts to enhance outcomes for women and infants affected by placenta previa.
PubMed: 38841031
DOI: 10.7759/cureus.59737 -
Journal of Perinatal Medicine Feb 2024Using cases from our own experience and from the published literature on amniotic fluid embolism (AFE), we seek to improve on existing criteria for diagnosis and discern... (Review)
Review
OBJECTIVES
Using cases from our own experience and from the published literature on amniotic fluid embolism (AFE), we seek to improve on existing criteria for diagnosis and discern associated risk factors. Additionally, we propose a novel theory of pathophysiology.
METHODS
This retrospective case review includes eight cases of AFE from two hospital systems and 21 from the published literature. All cases were evaluated using the modified criteria for research reporting of AFE by Clark et al. in Am J Obstet Gynecol, 2016;215:408-12 as well as our proposed criteria for diagnosis. Additional clinical and demographic characteristics potentially correlated with a risk of AFE were included and analyzed using descriptive analysis.
RESULTS
The incidence of AFE was 2.9 per 100,000 births, with five maternal deaths in 29 cases (17.2 %) in our series. None of the cases met Clark's criteria while all met our criteria. 62.1 % of patients were over the age of 32 years and two out of 29 women (6.9 %) conceived through fertilization. 6.5 % of cases were complicated by fetal death. Placenta previa occurred in 13.8 %. 86.2 % of women had cesarean sections of which 52.0 % had no acute maternal indication.
CONCLUSIONS
Our criteria identify more patients with AFE than others with a low likelihood of false positives. Clinical and demographic associations in our review are consistent with those previously reported. A possible relationship between cesarean birth and risk of AFE was identified using our criteria. Additionally, we propose a new hypothesis of pathophysiology.
Topics: Humans; Pregnancy; Female; Adult; Embolism, Amniotic Fluid; Retrospective Studies; Cesarean Section; Risk Factors; Incidence
PubMed: 38082418
DOI: 10.1515/jpm-2023-0365