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Balut : fertilized eggs and the making of culinary capital in the Filipino diaspora
\"Grounded in folkloristics and anthropology, Margaret Magat explores both the traditional and popular culture contexts of balut. Balut - fertilized duck or chicken eggs that have developed into fully formed embryos with feathers and beaks - is a delicacy which elicits passionate responses. Hailed as an aphrodisiac in Filipino culture, balut is often seen and used as an object of revulsion and disgust in western popular culture. Drawing on interviews, participant observation, reality television programs, travel shows,food blogs, and balut-eating contests, Magat examines balut production and consumption, its role in drinking rituals, sex, and the supernatural, vampire-like legends behind it. Balut reveals how traditional foods are used in the performance of identity and ethnicity, inspiring a virtual online cottage industry via social media as well as the impact globalization and migration are having on cultural practices and food consumption across the world. The first academic book on balut, this is essential reading for anyone in food studies, folklore studies, anthropology, and Asian American studies\"-- Provided by publisher.
Book
Embryo Politics
Since the first fertilization of a human egg in the laboratory in 1968, scientific and technological breakthroughs have raised ethical dilemmas and generated policy controversies on both sides of the Atlantic. Embryo, stem cell, and cloning research have provoked impassioned political debate about their religious, moral, legal, and practical implications. National governments make rules that govern the creation, destruction, and use of embryos in the laboratory-but they do so in profoundly different ways.
InEmbryo Politics, Thomas Banchoff provides a comprehensive overview of political struggles aboutembryo research during four decades in four countries-the United States, the United Kingdom, Germany, and France. Banchoff's book, the first of its kind, demonstrates the impact of particular national histories and institutions on very different patterns of national governance. Over time, he argues, partisan debate and religious-secular polarization have come to overshadow ethical reflection and political deliberation on the moral status of the embryo and the promise of biomedical research. Only by recovering a robust and public ethical debate will we be able to govern revolutionary life-science technologies effectively and responsibly into the future.
eBook
Does the transfer of a poor quality embryo with a good quality embryo benefit poor prognosis patients?
Background
While single embryo transfer (SET) is widely advocated, double embryo transfer (DET) remains preferable in clinical practice to improve IVF success rate, especially in poor prognosis patients with only poor quality embryos (PQEs) available in addition to one or no good quality embryos (GQEs). Furthermore, previous studies suggest PQE might adversely affect the implantation of a GQE when transferred together. This study aims to evaluate the effect of transferring an additional PQE with a GQE on the outcomes in poor prognosis patients.
Methods
A total of 5037 frozen-thawed blastocyst transfer (FBT) cycles between January 2012 and May 2019 were included. Propensity score matching was applied to control for potential confounders, and we used generalized estimating equations (GEE) models to identify the association between the effect of an additional PQE and the outcomes.
Results
Overall, transferring a PQE with GQE (Group GP) achieved significantly higher pregnancy rate (PR), live birth rate (LBR) and multiple pregnancy rate (MPR) than GQE only (group G). The addition of a PQE increased LBR in patients aged 35 and over and in patients who received over 3 cycles of embryo transfer (ET) (48.1% vs 27.2%, OR:2.56, 95% CI: 1.3–5.03 and 46.6% vs 35.4%, OR:1.6, 95% CI: 1.09–2.35), but not in women under 35 and in women who received less than 3 cycles of ET (48.7% vs 43.9%, OR:1.22, 95% CI: 0.93–1.59 and 48.3% vs 41.4%, OR:1.33, 95% CI: 0.96–1.85). Group GP resulted in significantly higher MPR than group G irrespective of age and the number of previous IVF cycles.
Conclusions
An additional PQE does not negatively affect the implantation potential of the co-transferred GQE. Nevertheless, the addition of a PQE contributes to both live birth and multiple birth in poor prognosis patients. Physicians should still balance the benefits and risks of DET.
Journal Article
Comparisons of benefits and risks of single embryo transfer versus double embryo transfer: a systematic review and meta-analysis
Background
Evidence referring to the trade-offs between the benefits and risks of single embryo transfer (SET) versus double embryo transfer (DET) following assisted reproduction technology are insufficient, especially for those women with a defined embryo quality or advanced age.
Methods
A systematic review and meta-analysis was conducted according to PRISMA guidelines. PubMed, EMBASE, Cochrane Library and
ClinicalTrials.gov
were searched based on established search strategy from inception through February 2021. Pre-specified primary outcomes were live birth rate (LBR) and multiple pregnancy rate (MPR). Odds ratio (OR) with 95% confidence interval (CI) were pooled by a random-effects model using R version 4.1.0.
Results
Eighty-five studies (14 randomized controlled trials and 71 observational studies) were eligible. Compared with DET, SET decreased the probability of a live birth (OR = 0.78, 95% CI: 0.71–0.85,
P <
0.001,
n
= 62), and lowered the rate of multiple pregnancy (0.05, 0.04–0.06,
P <
0.001,
n
= 45). In the sub-analyses of age stratification, both the differences of LBR (0.87, 0.54–1.40,
P
= 0.565,
n
= 4) and MPR (0.34, 0.06–2.03,
P
= 0.236,
n
= 3) between SET and DET groups became insignificant in patients aged ≥40 years. No significant difference in LBR for single GQE versus two embryos of mixed quality [GQE + PQE (non-good quality embryo)] (0.99, 0.77–1.27,
P =
0.915,
n
= 8), nor any difference of MPR in single PQE versus two PQEs (0.23, 0.04–1.49,
P =
0.123,
n
= 6). Moreover, women who conceived through SET were associated with lower risks of poor outcomes, including cesarean section (0.64, 0.43-0.94), antepartum haemorrhage (0.35, 0.15-0.82), preterm birth (0.25, 0.21-0.30), low birth weight (0.20, 0.16-0.25), Apgar1 < 7 rate (0.12, 0.02-0.93) or neonatal intensive care unit admission (0.30, 0.14-0.66) than those following DET.
Conclusions
In women aged < 40 years or if any GQE is available, SET should be incorporated into clinical practice. While in the absence of GQEs, DET may be preferable. However, for elderly women aged ≥40 years, current evidence is not enough to recommend an appropriate number of embryo transfer. The findings need to be further confirmed.
Journal Article
Impact of Group vs Individual Embryo Culture Strategies on Blastocyst and Clinical Outcomes
Embryo culture is one of the most important steps in an assisted reproduction laboratory. Embryos can be cultured individually, one embryo per media drop, or in groups, culturing several embryos in the same media drop. Due to the controversy generated on this subject, we wondered which embryo culture method would have the best results in terms of quality and blastocyst formation rate. We designed a prospective randomized study comparing two different embryo culture strategies: group and individual embryo culture. The data were obtained from 830 embryos from 103 egg donation treatments. The zygotes were randomized into two groups: individual culture (group 1) or group culture (group 2). The embryos were cultured in 35-µl drops until day 5 when they were classified morphologically. We observed a significant increase in the blastocyst formation rate and in the usable embryo rate in individual culture on day 5 compared to group culture. However, good embryo quality (A/B blastocysts), implantation, and pregnancy rates were similar regardless of the type of embryo-culture. As a conclusion, individual culture may increase blastocyst formation rate and may benefit embryo quality on day 5. Our results support previous reports suggesting that individual culture could improve embryo development.
Journal Article
Measuring the serum progesterone level on the day of transfer can be an additional tool to maximize ongoing pregnancies in single euploid frozen blastocyst transfers
Background
Endometrial preparation with hormone replacement therapy (HRT) is the preferred regimen for clinicians due to the opportunity to schedule the day of embryo transfer and for patients due to the requirement of fewer visits for frozen-warmed embryo transfers (FET). The increasing number of FETs raises the question of the serum P levels required to optimize the pregnancy outcome on the embryo transfer day.
Methods
This prospective cohort study includes patients who underwent single euploid FET. All patients received HRT with oestradiol valerate (EV) and 100 mg of intramuscular (IM) progesterone (P). FET was scheduled 117–120 h after the first IM administration of 100 mg P. The serum P level was analyzed 1 h before the embryo transfer (ET). In all cycles, only embryos that were biopsied on day 5 were utilized for FET. Next generation sequencing (NGS) was used for comprehensive chromosomal analysis.
Results
Overall, the ongoing pregnancy rate (OPR) was 58.9% (99/168). Data were then categorized according to the presence (Group I;
n
= 99) or the absence (Group II;
n
= 69) of an ongoing pregnancy. No significant differences regarding, female age, body mass index (BMI), number of previous miscarriages, number of previous live birth, sperm concentration, number of oocytes retrieved, number of mature oocytes (MII), rate of fertilized oocytes with two pronuclei (2PN), trophectoderm score, inner cell mass (ICM) score, endometrial thickness (mm), oestrodiol (E
2
) and P levels prior to IM P administration were found between two groups. The P levels on the day of ET (ng/ml) were significantly higher in Group I (28 (5.6–76.4) vs 16.4 (7.4–60)
p
= 0.039). The P level on the day of ET was a predictor of a higher OPR (
p
< 0.001 OR: 1.033 95%CI [1.009–1.056]) after multivariate analysis. The ROC curve showed a significant predictive value of serum P levels on the day of ET for OPR, with an AUC (95%CI) = 0.716 (0.637–0.795). The optimal cut-off value for prediction of the OPR was a P level of 20.6 ng/ml (71.7% sensitivity, 56.5% specificity).
Conclusions
The present study suggests a minimum threshold of the serum
P
value on the day of ET that needs to be reached in HRT cycles to optimize the clinical outcome. Individualization of the P dosage should be evaluated in further studies.
Journal Article