The effect of higher estradiol levels during stimulation on pregnancy complications and placental histology

High estradiol levels in fresh embryo transfer cycles are not associated with detrimental impact on birth outcomes

PURPOSE

There is an unclear relationship between estradiol levels and fresh embryo transfer (ET) outcomes. We determined the relationship between estradiol on the day of trigger, in fresh ET cycles without premature progesterone elevation, and good birth outcomes (GBO).

METHODS

We identified autologous fresh ET cycles from 2015 to 2021 at multiple clinics in the USA. Patients with recurrent pregnancy loss, uterine factor, and elevated progesterone on the day of trigger (progesterone > 2 ng/mL or 3-day area under the curve > 4.5 ng/mL) were excluded. The primary outcome was GBO (singleton, term, live birth with appropriate weight). Log-binomial generalized estimating equations determined the likelihood of outcomes.

RESULTS

Of 17,608 fresh ET cycles, 5025 (29%) yielded GBO. Cycles with estradiol ≥ 4000 pg/mL had a greater likelihood of GBO compared to cycles < 1000 pg/mL (aRR = 1.32, 95% CI 1.13-1.54). Pairwise comparisons of estradiol between < 1000 pg/mL versus 1000-1999 pg/mL and 1000-1999 pg/mL versus 2000-2999 pg/mL revealed a higher likelihood of GBO with higher estradiol (aRR 0.83, 95% CI 0.73-0.95; aRR 0.91, 95% CI 0.85-0.97, respectively). Comparisons amongst more elevated estradiol levels revealed that the likelihood of GBO remained similar between groups (2000-2999 pg/mL versus 3000-3999 pg/mL, aRR 1.04, 95% CI 0.97-1.11; 3000-3999 pg/mL versus ≥ 4000 pg/mL, aRR 0.96, 95% CI 0.9-1.04).

CONCLUSION

In fresh ET cycles, higher estradiol levels were associated with an increased prevalence of GBO until estradiol 2000-2999 pg/mL, thereafter plateauing. In fresh ET candidates, elevated estradiol levels should not preclude eligibility though premature progesterone rise, and risk of ovarian hyperstimulation syndrome must still be considered.

High estrogen during ovarian stimulation induced loss of maternal imprinted methylation that is essential for placental development via overexpression of TET2 in mouse oocytes

BACKGROUND

Ovarian stimulation (OS) during assisted reproductive technology (ART) appears to be an independent factor influencing the risk of low birth weight (LBW). Previous studies identified the association between LBW and placenta deterioration, potentially resulting from disturbed genomic DNA methylation in oocytes caused by OS. However, the mechanisms by which OS leads to aberrant DNA methylation patterns in oocytes remains unclear.

METHODS

Mouse oocytes and mouse parthenogenetic embryonic stem cells (pESCs) were used to investigate the roles of OS in oocyte DNA methylation. Global 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) levels were evaluated using immunofluorescence or colorimetry. Genome-wide DNA methylation was quantified using an Agilent SureSelectXT mouse Methyl-Seq. The DNA methylation status of mesoderm-specific transcript homologue (Mest) promoter region was analyzed using bisulfite sequencing polymerase chain reaction (BSP). The regulatory network between estrogen receptor alpha (ERα, ESR1) and DNA methylation status of Mest promoter region was further detected following the knockdown of ERα or ten-eleven translocation 2 (Tet2).

RESULTS

OS resulted in a significant decrease in global 5mC levels and an increase in global 5hmC levels in oocytes. Further investigation revealed that supraphysiological β-estradiol (E2) during OS induced a notable decrease in DNA 5mC and an increase in 5hmC in both oocytes and pESCs of mice, whereas inhibition of estrogen signaling abolished such induction. Moreover, Tet2 may be a direct transcriptional target gene of ERα, and through the ERα-TET2 axis, supraphysiological E2 resulted in the reduced global levels of DNA 5mC. Furthermore, we identified that MEST, a maternal imprinted gene essential for placental development, lost its imprinted methylation in parthenogenetic placentas originating from OS, and ERα and TET2 combined together to form a protein complex that may promote Mest demethylation.

CONCLUSIONS

In this study, a possible mechanism of loss of DNA methylation in oocyte caused by OS was revealed, which may help increase safety and reduce epigenetic abnormalities in ART procedures.

The effect of oestrogen dose and duration in programmed frozen cycles on obstetric outcomes and placental findings

RESEARCH QUESTION

Does programmed frozen embryo transfer (FET) with high-dose oestrogen affect obstetric outcomes and placental findings?

DESIGN

A retrospective cohort of live singleton deliveries at a single institution between 2009 and 2017, including deliveries attained by IVF with programmed FET; oocyte recipients were excluded. High-dose oestrogen was defined as a daily dose >6 mg throughout treatment. All placentas were evaluated regardless of complication status and the Amsterdam classification was used to analyse findings.

RESULTS

A total of 57 deliveries in the high-dose oestrogen group were compared with 274 controls. The high-dose oestrogen group displayed significantly longer duration of oestrogen treatment (18.8 ± 4.9 versus 13.3 ± 2.7 days, P < 0.001), total cumulative oestrogen dose (149.7 ± 46.1 versus 80.3 ± 16.8 mg, P < 0.001) and lower endometrial thickness (8.5 ± 1.4 versus 9.8 ± 1.7 mm, P < 0.001). After adjustment for confounders, higher dose oestrogen was found to be associated with a lower average birthweight (coefficient -252.4 g, 95% confidence interval [CI] -483.5 to -21.2), a higher rate of low-birthweight neonates (adjusted odds ratio [aOR] 4.88, 95% CI 1.05 to 22.57), bilobated placentas (aOR 3.36, 95% CI 1.04 to 10.89), accessory lobes (aOR 8.74, 95% CI 1.24 to 61.5), accelerated villous maturation (aOR 2.06, 95% CI 1.09 to 3.87), retroplacental haematoma (aOR 5.39, 95% CI 1.11 to 26.13) and maternal malperfusion lesions (aOR 1.46, 95% CI 1.04 to 2.05).

CONCLUSION

A higher daily oestrogen dose in programmed FET is associated with low birthweight and placental changes, although this may relate to altered endometrial properties and not to the treatment itself.

Does a history of recurrent pregnancy loss affect subsequent obstetric outcomes and placental findings in in vitro fertilization?

PURPOSE

To assess perinatal outcomes and placental findings in in vitro fertilization (IVF) patients with previous recurrent pregnancy loss (RPL).

METHODS

This was a retrospective cohort of live singleton births following IVF at a single university-affiliated center between 2009 and 2017. Outcomes were compared between patients with previous RPL, defined as two miscarriages (RPL group), and patients without RPL (control group). Placental examination was performed for all deliveries irrelevant of complications, and findings categorized according to the Amsterdam Placental Workshop Consensus.

RESULTS

One hundred seventy-two deliveries of women with previous RPL (RPL group) were compared to 885 controls. Maternal age, 36.2 ± 4.2 vs. 35.4 ± 4.2 years, p = 0.02, and rate of uterine fibroids, 12.7% vs. 7.3%, p = 0.01, were higher in the RPL group. The rate of nulliparity was lower in the RPL group, 63.3% vs. 74.1%, p = 0.003. Unexplained infertility and diminished ovarian reserve were more common in the RPL group and male factor infertility in controls. There was a lower rate of fresh embryo transfer in the RPL group, 50.5% vs. 64.7%, p < 0.001, and reduced endometrial thickness. Similar obstetric outcomes were noted in the groups after adjustment for confounders. Placental examinations were notable for lower placental thickness, β - 0.17 cm, 95%CI - 0.30-(- 0.0), a lower rate of velamentous cord insertion, aOR 0.44, 95%CI 0.20-0.95, and a higher rate of villous infarction, aOR 2.82, 95%CI 1.28-6.20 in the RPL group.

CONCLUSION

In IVF patients with a history of RPL, subsequent deliveries were associated with a limited number of placental lesions, yet with similar obstetric outcomes.

Recent Advances in the Synthesis, Characterization, and Application of Carbon Nanomaterials for the Removal of Endocrine-Disrupting Chemicals: A Review

The large-scale production and frequent use of endocrine-disrupting chemicals (EDCs) have led to the continuous release and wide distribution of these pollutions in the natural environment. At low levels, EDC exposure may cause metabolic disorders, sexual development, and reproductive disorders in aquatic animals and humans. Adsorption treatment, particularly using nanocomposites, may represent a promising and sustainable method for EDC removal from wastewater. EDCs could be effectively removed from wastewater using various carbon-based nanomaterials, such as carbon nanofiber, carbon nanotubes, graphene, magnetic carbon nanomaterials, carbon membranes, carbon dots, carbon sponges, etc. Important applications of carbon nanocomposites for the removal of different kinds of EDCs and the theory of adsorption are discussed, as well as recent advances in carbon nanocomposite synthesis technology and characterization technology. Furthermore, the factors affecting the use of carbon nanocomposites and comparisons with other adsorbents for EDC removal are reviewed. This review is significant because it helps to promote the development of nanocomposites for the decontamination of wastewater.