Recent advances in the field of ovarian tissue cryopreservation and opportunities for research.

PURPOSE: The purpose of this study was to summarize the latest advances and successes in the field of ovarian tissue cryopreservation while identifying gaps in current knowledge that suggest opportunities for future research. METHODS: A systematic review was performed according to PRISMA guidelines for all relevant full-text articles in PubMed published in English that reviewed or studied historical or current advancements in ovarian tissue cryopreservation and auto-transplantation techniques. RESULTS: Ovarian tissue auto-transplantation in post-pubertal women is capable of restoring fertility with over 80 live births currently reported with a corresponding pregnancy rate of 23 to 37%. The recently reported successes of live births from transplants, both in orthotopic and heterotopic locations, as well as the emerging methods of in vitro maturation (IVM), in vitro culture of primordial follicles, and possibility of in vitro activation (IVA) suggest new fertility options for many women and girls. Vitrification, as an ovarian tissue cryopreservation technique, has also demonstrated successful live births and may be a more cost-effective method to freezing with less tissue injury. Further, transplantation via the artificial ovary with an extracellular tissue matrix (ECTM) scaffolding as well as the effects of sphingosine-1-phosphate (SIP) and fibrin modified with heparin-binding peptide (HBP), heparin, and a vascular endothelial growth factor (VEGF) have demonstrated important advancements in fertility preservation. As a fertility preservation method, ovarian tissue cryopreservation and auto-transplantation are currently considered experimental, but future research may pave the way for these modalities to become a standard of care for women facing the prospect of sterility from ovarian damage.

Investigation of Intrapartum Parenteral Magnesium Sulfate as an Independent Risk Factor for Postpartum Hemorrhage Using Quantitative Blood Loss Assessment.

BACKGROUND: Magnesium sulfate is used for seizure prophylaxis in preeclampsia and for fetal neuroprotection when delivery is anticipated before 32 weeks of gestation. Existing risk assessment tools for postpartum hemorrhage often identify the use of magnesium sulfate as an intrapartum risk factor. Previous studies examining the association between the use of magnesium sulfate and postpartum hemorrhage have relied largely on qualitative estimates of blood loss rather than quantitative estimates of blood loss. OBJECTIVE: This study aimed to determine whether intrapartum administration of magnesium sulfate is associated with an increased risk of postpartum hemorrhage using a quantitative blood loss assessment via the use of graduated drapes and weight differences in surgical supplies. STUDY DESIGN: This case-control study was conducted to test the hypothesis that intrapartum parenteral administration of magnesium sulfate is not independently associated with postpartum hemorrhage. All deliveries at our tertiary-level academic medical center between July 2017 and June 2018 were reviewed. Of note, 2 categories of postpartum hemorrhage were defined: the traditional definition (>500 mL for vaginal delivery and >1000 mL for cesarean delivery) and the contemporary definition (>1000 mL regardless of delivery mode). Statistical analyses using the chi-square test, Fisher exact test, t test, or Wilcoxon rank-sum test were performed to compare the patients who did and did not receive magnesium sulfate concerning the rates of postpartum hemorrhage, pre- and postdelivery hemoglobin level, and rates of blood transfusion. RESULTS: A total of 1318 deliveries were included, with postpartum hemorrhage rates of 12.2% (traditional definition) and 6.2% (contemporary definition). Multivariate logistic regression did not find the use of magnesium sulfate as an independent risk factor by either definition (odds ratio, 1.44 [95% confidence interval, 0.87-2.38] and 1.34 [95% confidence interval, 0.71-2.54]). The only significant independent risk factor was cesarean delivery, by both definitions (odds ratio, 2.71 [95% confidence interval, 1.85-3.98] and 19.34 [95% confidence interval, 8.55-43.72]). CONCLUSION: In our study population, intrapartum administration of magnesium sulfate was not found to be an independent risk factor for postpartum hemorrhage. Cesarean delivery was determined as an independent risk factor, consistent with previous reports.

Maternal outcomes according to cesarean uterine incision between 23 and 27 weeks' gestation.

OBJECTIVE: Cesarean delivery between 23 and 27 weeks' gestation is a risk factor for performing classical and inverted T uterine incisions. When attempting cesarean delivery via a low transverse incision at a very preterm gestational age, having difficulty in delivery of the fetus may require conversion to an inverted T-incision. We sought to examine maternal short-term outcomes according to the type of attempted uterine incisions in preterm deliveries. STUDY DESIGN: This was a multihospital retrospective cohort study of women undergoing cesarean delivery between 23 0/7 and 27 6/7 week' gestation from 2005 through 2014. Cases were classified as attempting low transverse incision if the uterine incision was a low transverse or an inverted T incision. Composite maternal outcome (postpartum hemorrhage, transfusion, endometritis, sepsis, wound infection, deep venous thrombosis/pulmonary embolism, hysterectomy, respiratory complications, and intensive care unit admission) was compared between cases where a low transverse incision was attempted and those with a classical uterine incision. We also examined operative time and Apgar score at 5 minutes. Multivariable logistic regression or linear regression was used to obtain adjusted p-value or adjusted odds ratios (aOR) with 95% confidence interval (95%CI), controlling for maternal age, gestational age, body mass index (kg/m2), and preterm premature rupture of membranes. RESULTS: Of 311 women undergoing cesarean delivery between 23 0/7 and 27 6/7 week' gestation, attempting low transverse incision occurred in 127 (41%). Of these, conversion to an inverted T or J uterine incision occurred in 14 (11%). There was no difference in the composite outcome between cases with attempting low transverse incision and those with classical incision (17.3 versus 23.4%, respectively; aOR 0.58 [95%CI 0.30-1.11]). Cases in which a low transverse uterine incision was attempted had shorter median operative time (46 versus 55 minutes; adjusted p-value < 0.01). No differences were seen in the Apgar score at 5 minutes (adjusted p-value = .81). CONCLUSION: The incidence of conversion from a low transverse to an inverted T uterine incision in very preterm cesarean deliveries was low. Attempting a low transverse compared to a classical uterine incision was associated with similar odds of the primary outcome and shorter operative time.

Mechanical homeostasis is altered in uterine leiomyoma.

OBJECTIVE: Uterine leiomyoma produce an extracellular matrix (ECM) that is abnormal in its volume, content, and structure. Alterations in ECM can modify mechanical stress on cells and lead to activation of Rho-dependent signaling and cell growth. Here we sought to determine whether the altered ECM that is produced by leiomyoma was accompanied by an altered state of mechanical homeostasis. STUDY DESIGN: We measured the mechanical response of paired leiomyoma and myometrial samples and performed immunogold, confocal microscopy, and immunohistochemical analyses. RESULTS: Leiomyoma were significantly stiffer than matched myometrium. The increased stiffness was accompanied by alteration of the ECM, cell shape, and cytoskeleton in leiomyoma, compared with myometrial samples from the same uterus. Levels of AKAP13, a protein that is known to activate Rho, were increased in leiomyoma compared to myometrium. AKAP13 was associated with cytoskeletal filaments of immortalized leiomyoma cells. CONCLUSION: Leiomyoma cells are exposed to increased mechanical loading and show structural and biochemical features that are consistent with the activation of solid-state signaling.