Is Preimplantation Genetic Testing Associated with Increased Risk of Abnormal Placentation After Frozen Embryo Transfer?

OBJECTIVE: This study aimed to assess the association of preimplantation genetic testing (PGT) with abnormal placentation among a cohort of pregnancies conceived after frozen embryo transfer (FET). STUDY DESIGN: This is a retrospective cohort study of women who conceived via FET at the University of California, San Francisco from 2012 to 2016 with resultant delivery at the same institution. The primary outcome was abnormal placentation, including placenta accreta, retained placenta, abruption, placenta previa, vasa previa, marginal or velamentous cord insertion, circumvallate placenta, circummarginate placenta, placenta membranacea, bipartite placenta, and placenta succenturiata. Diagnosis was confirmed by reviewing imaging, delivery, and pathology reports. Our secondary outcome was hypertensive disease of pregnancy. RESULTS: A total of 311 pregnancies were included in analysis; 158 (50.8%) underwent PGT. Baseline demographic characteristics were similar between groups except for age at conception and infertility diagnosis. Women with PGT were more likely to undergo single embryo transfer (82.3 vs. 64.1%, p < 0.001). There were no statistically significant differences in the rate of the primary outcome (26.6 vs. 27.4%, p = 0.86) or hypertensive disorders of pregnancy (33.5 vs. 33.3%, p = 0.97), which remained true after multivariate analysis was performed. CONCLUSION: Among pregnancies conceived after FET, PGT is not associated with a statistically significant increased risk of abnormal placentation or hypertensive disorders of pregnancy. KEY POINTS: · In pregnancies conceived by FET, PGT is not associated with increased risk of abnormal placentation.. · In pregnancies conceived by FET, PGT is not associated with increased risk of hypertensive disorders.. · Differences in outcomes of PGT pregnancies may be related to FET rather than trophectoderm biopsy..

The Case for Standardizing Cesarean Delivery Technique: Seeing the Forest for the Trees.

In this Commentary, we explain the case for a standardized cesarean delivery surgical technique. There are three strong arguments for a standardized approach to cesarean delivery, the most common major abdominal surgery performed in the world. First, standardization within institutions improves safety, efficiency, and effectiveness in health care delivery. Second, surgical training among obstetrics and gynecology residents would become more consistent across hospitals and regions, and proficiency in performing cesarean delivery measurable. Finally, standardization would strengthen future trials of cesarean delivery technique by minimizing the potential for aspects of the surgery which are not being studied to bias results. Before 2013, more than 155 randomized controlled trials, meta-analyses or systematic reviews were published comparing various aspects of cesarean delivery surgical technique. Since 2013, an additional 216 similar studies have strengthened those recommendations and offered evidence to recommend additional cesarean delivery techniques. However, this amount of cesarean delivery technique data creates a forest for the trees problem, making it difficult for a clinician to synthesize this volume of data. In response to this difficulty, we propose a comprehensive, evidence-based and standardized approach to cesarean delivery technique.

Prevention of RhD Alloimmunization: A Comparison of Four National Guidelines.

OBJECTIVE: The objective of this study was to compare national guidelines on the prevention of RhD alloimmunization. STUDY DESIGN: We performed a review of four national guidelines on prevention of alloimmunization from the American Congress of Obstetricians and Gynecologists, Royal College of Obstetricians and Gynaecologists, Society of Obstetricians and Gynaecologists of Canada, and The Royal Australian and New Zealand College of Obstetricians and Gynaecologists. We compared the indications/contraindications, timing, dosing, formulation and route of anti-D immune globulin, and management of unique circumstances. The references were compared with regard to the number of randomized control trials, Cochrane Reviews, and systematic reviews/meta-analyses cited. RESULTS: Variation exists in recommendations on the timing and need for consent prior to routine antenatal anti-D immune globulin administration, prophylaxis for unique circumstances (e.g., threatened abortion < 12 weeks, complete molar pregnancy), and the use of cell-free fetal DNA testing for fetal RhD genotype. CONCLUSION: These variations in recommendations reflect the heterogeneity of the literature on the prevention of alloimmunization and highlight the need for synthesis of evidence to create an international guideline on prevention of alloimmunization. This may improve safety, quality, optimize outcomes, and stimulate future trials.

Evidence-Based Cesarean Delivery for the Nonobstetrician.

Cesarean delivery (CD) is one of the most common major surgeries performed in the United States and worldwide. Surgical techniques evaluated in well-designed randomized controlled trials (RCTs) that demonstrate maternal benefit should be incorporated into practice. The objective of this review is to provide a summary of surgical techniques of the procedure and review the evidence basis for them for the nonobstetrician. The following techniques with the strongest evidence should be commonly performed, when feasible: (1) prophylactic antibiotics with a single dose of ampicillin or first-generation cephalosporin prior to skin incision; (2) postpartum hemorrhage prevention with oxytocin infusion of 10 to 40 IU in 1 L crystalloid over 4 to 8 hours; (3) low transverse skin incision; (4) blunt or sharp subcutaneous and fascial expansion; (5) blunt, cephalad-caudad uterine incision expansion; (6) spontaneous placental removal; (7) blunt-tip needle usage during closure; (8) subcutaneous suture closure (running or interrupted) if thickness is ≥2 cm; and (9) skin closure with suture. Although the number of RCTs designed to optimize maternal and neonatal outcomes of this common procedure is encouraging, further work is needed to minimize surgical morbidity. Optimal methods for postpartum hemorrhage prevention, adhesion prevention, and venous thromboembolism prophylaxis remain ongoing areas of active research, with outcomes that could markedly improve maternal morbidity and mortality. If evidence of a surgical technique appears preferred over another, clinicians should be comfortable adopting the evidence-based technique when performing and teaching CD.