Increased miscarriage of euploid pregnancies in obese women undergoing cryopreserved embryo transfer

Which factors affect the live birth outcome of the first single euploid frozen-thawed blastocyst transfer in couples with balanced chromosomal translocations?

Objective

The objective of this study is to investigate the factors that influence the live birth rate (LBR) of the first single euploid frozen-thawed blastocyst transfer (FBT) cycles after preimplantation genetic testing for structural rearrangements (PGT-SR) in couples with balanced chromosomal translocations (BCT).

Design

Single center, retrospective and observational study.

Methods

A total of 336 PGT-SR and the first single euploid FBT cycles between July 2016 and December 2022 were included in this study. The patients were divided into two groups according to the live birth outcomes. The parameters of the study population, controlled ovarian stimulation cycles, and FBT cycles were analyzed. Multivariable binary logistic regression was performed to find the factors that affected the LBR.

Results

The percentage of blastocysts at developmental stage Day 5 compared to Day 6 (51.8% vs. 30.8%; P<0.001) and with morphology ≥BB compared to

Conclusion

The developmental stage and morphology of blastocyst affect the live birth outcome of the first single euploid FBT in BCT carriers undergoing PGT-SR.

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Key Words

• balanced chromosomal translocations
• euploid
• frozen-thawed blastocyst transfer
• live birth
• preimplantation genetic testing for structural rearrangements (PGT-SR)

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MESH Headings

• Humans
• Female
• Pregnancy
• Retrospective Studies
• Live Birth
• Translocation, Genetic
• Adult
• Embryo Transfer/methods
• Male
• Cryopreservation
• Pregnancy Rate
• Preimplantation Diagnosis/methods
• Birth Rate
• Fertilization in Vitro/methods
• Pregnancy Outcome
• Blastocyst
• Ovulation Induction/methods

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Affiliation(s)

Ruixiao Zhang Reproductive Medicine Center, Henan Provincial People’s Hospital, Zhengzhou, China Reproductive Medicine Center, Zhengzhou University People’s Hospital, Zhengzhou, China Reproductive Medicine Center, Henan University People’s Hospital, Zhengzhou, China
Yahui Hu Reproductive Medicine Center, Henan Provincial People’s Hospital, Zhengzhou, China Reproductive Medicine Center, Zhengzhou University People’s Hospital, Zhengzhou, China Reproductive Medicine Center, Henan University People’s Hospital, Zhengzhou, China
Chenchen Cui Reproductive Medicine Center, Henan Provincial People’s Hospital, Zhengzhou, China Reproductive Medicine Center, Zhengzhou University People’s Hospital, Zhengzhou, China Reproductive Medicine Center, Henan University People’s Hospital, Zhengzhou, China
Cuilian Zhang Reproductive Medicine Center, Henan Provincial People’s Hospital, Zhengzhou, China Reproductive Medicine Center, Zhengzhou University People’s Hospital, Zhengzhou, China Reproductive Medicine Center, Henan University People’s Hospital, Zhengzhou, China

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Higher live birth rates are associated with a normal body mass index in preimplantation genetic testing for aneuploidy frozen embryo transfer cycles: a Society for Assisted Reproductive Technology Clinic Outcome Reporting System study

OBJECTIVE

To determine whether body mass index (BMI) was associated with live birth in patients undergoing transfer of frozen-thawed preimplantation genetic testing for aneuploidy (PGT-A) embryos.

DESIGN

Retrospective cohort study of cycles reported to the Society for Assisted Reproductive Technology Clinic Outcome Reporting System.

SUBJECTS

All autologous and donor recipient PGT-A-tested cycles reported to the Society for Assisted Reproductive Technology Clinic Outcome Reporting System from 2014 to 2017.

INTERVENTION(S)

Body mass index.

MAIN OUTCOME MEASURE(S)

The primary outcome measure was the live birth rate, and the secondary outcome measures were the clinical pregnancy and biochemical pregnancy rates. Multivariable generalized additive mixed models and log-binomial models were used to model the relationship between BMI and outcome measures.

RESULT(S)

A total of 77,018 PGT-A cycles from 55,888 patients were analyzed. Of these cycles, 70,752 were autologous, and 6,266 were donor recipient. In autologous cycles, a statistically significant and clear nonlinear relationship was observed between the BMI and live birth rates, with the highest birth rates observed for the BMI range of 23-24.99 kg/m2. When using 23-24.99 kg/m2 as the referent, other BMI ranges demonstrated a lower probability of live birth and clinical pregnancy that continued to decrease as the BMI moved further from the reference value. Patients with a BMI of <18.5 kg/m2 had a 11% lower probability of live birth, whereas those with a BMI of ≥40 kg/m2 had a 27% lower probability than the referent.

CONCLUSION(S)

A normal-weight BMI range of 23-24.99 kg/m2 was associated with the highest probability of clinical pregnancy and live birth after a frozen-thawed PGT-A-tested blastocyst transfer in both autologous and donor recipient cycles. A BMI outside the range of 23-24.99 kg/m2 is likely associated with a malfunction in the implantation process, which is presumed to be related to a uterine factor and not an oocyte factor, as both autologous and donor recipient cycle outcomes were associated similarly with the BMI of the intended parent.

Frozen embryo transfer outcomes decline with increasing female body mass index in female but not male factor infertility: analysis of 56,564 euploid blastocyst transfers

OBJECTIVE

To evaluate the association of body mass index (BMI) with cycle outcomes after euploid frozen blastocyst transfer.

DESIGN

Retrospective cohort study.

SETTING

Not applicable.

PATIENT(S)

A total of 56,564 first single autologous euploid frozen embryo transfers from the 2016-2019 Society for Assisted Reproductive Technology database were analyzed using BMI and using World Health Organization BMI cohorts. Subanalyses were performed on cycles among patients with a sole diagnosis of polycystic ovary syndrome (PCOS) (n = 4,626) and among patients with only a male factor (n = 10,854).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy, pregnancy loss, and live birth (LB).

RESULT(S)

Success rates and adjusted odds ratios (aORs) with 95% confidence intervals (CIs) for all outcomes were most favorable among those with normal BMI and progressively worsened with increasing BMI. These trends persisted among patients with PCOS for clinical pregnancy (aOR, 0.99; 95% CI, 0.98-0.997), pregnancy loss (aOR, 1.02; 95% CI, 1.01-1.04), and LB (aOR, 0.98; 95% CI, 0.97-0.99), but not among patients with a male factor only for clinical pregnancy (aOR, 1.00; 95% CI, 0.99-1.01), pregnancy loss (aOR, 1.01; 95% CI, 0.99-1.03), or LB (aOR, 0.99; 95% CI, 0.98-1.00).

CONCLUSION(S)

In the largest cohort to date, increasing BMI was associated with decreased pregnancy and LB and increased pregnancy loss after euploid frozen embryo transfers among the entire cohort and among patients with a sole diagnosis of PCOS; however, these results were attenuated among patients with a sole diagnosis of male factor infertility, suggesting that associated female infertility diagnoses and not BMI alone may underlie this trend.

How the Oviduct Lipidomic Profile Changes over Time after the Start of an Obesogenic Diet in an Outbred Mouse Model

We investigated whether a high-fat/high-sugar (HF/HS) diet alters the lipidomic profile of the oviductal epithelium (OE) and studied the patterns of these changes over time. Female outbred Swiss mice were fed either a control (10% fat) or HF/HS (60% fat, 20% fructose) diet. Mice (n = 3 per treatment per time point) were sacrificed and oviducts were collected at 3 days and 1, 4, 8, 12 and 16 weeks on the diet. Lipids in the OE were imaged using matrix-assisted laser desorption ionisation mass spectrometry imaging. Discriminative m/z values and differentially regulated lipids were determined in the HF/HS versus control OEs at each time point. Feeding the obesogenic diet resulted in acute changes in the lipid profile in the OE already after 3 days, and thus even before the development of an obese phenotype. The changes in the lipid profile of the OE progressively increased and became more persistent after long-term HF/HS diet feeding. Functional annotation revealed a differential abundance of phospholipids, sphingomyelins and lysophospholipids in particular. These alterations appear to be not only caused by the direct accumulation of the excess circulating dietary fat but also a reduction in the de novo synthesis of several lipid classes, due to oxidative stress and endoplasmic reticulum dysfunction. The described diet-induced lipidomic changes suggest alterations in the OE functions and the oviductal microenvironment which may impact crucial reproductive events that take place in the oviduct, such as fertilization and early embryo development.

The association of gut microbiome with recurrent pregnancy loss: A comprehensive review

The steady-state gut microbiome not only promotes the metabolism and absorption of nutrients that are difficult to digest by the host itself, but also participates in systemic metabolism. Once the dynamic balance is disturbed, the gut microbiome may lead to a variety of diseases. Recurrent pregnancy loss (RPL) affects 1-2% of women of reproductive age, and its prevalence has increased in recent years. According to the literature review, the gut microbiome is a new potential driver of the pathophysiology of recurrent abortion, and the gut microbiome has emerged as a new candidate for clinical prevention and treatment of RPL. However, few studies have concentrated on the direct correlation between RPL and the gut microbiome, and the mechanisms by which the gut microbiome influences recurrent miscarriage need further investigation. In this review, the effects of the gut microbiome on RPL were discussed and found to be associated with inflammatory response, the disruption of insulin signaling pathway and the formation of insulin resistance, maintenance of immunological tolerance at the maternal-fetal interface due to the interference with the immune imbalance of Treg/Th17 cells, and obesity.

Detrimental actions of obesity-associated advanced glycation end-products on endometrial epithelial cell proliferation are alleviated by antioxidants

RESEARCH QUESTION

Advanced glycation end-products (AGE) are elevated in the uterine environment of obese infertile women. Can the detrimental effects of AGE on endometrial epithelial cells be mitigated with therapeutics, and recapitulated in a more physiologically relevant primary model (organoids)?

DESIGN

Human endometrial epithelial cells (ECC-1) were exposed to AGE at concentrations physiologically representative of uterine fluid in lean or obese individuals, and three potential therapeutics: 25 nmol/l receptor for AGE (RAGE) antagonist FPS-ZM1, 100 μmol/l metformin, or a combination of antioxidants (10 μmol/l N-acetyl-l-cysteine, 10 μmol/l N-acetyl-l-carnitine and 5 μmol/l α-lipoic acid). Real-time cell analysis (xCELLigence, ACEA Biosciences) determined the rate of adhesion and proliferation. The proliferation of organoid-derived cells and secretion of cytokines from organoids was characterized in the presence of AGE (n = 5). The uterine fluid of women undergoing assisted reproduction was profiled for AGE-associated inflammatory markers (n = 77).

RESULTS

ECC-1 proliferation was reduced by AGE from obese versus lean conditions and vehicle control (P = 0.04 and P < 0.001, respectively), and restored to a proliferation corresponding to lean conditions by antioxidants. AGE influenced organoid derived primary endometrial epithelial cell proliferation in a donor-dependent manner. AGE increased the organoid secretion of the proinflammatory cytokine CXCL16 (P = 0.006). Clinically, CXCL16 correlated positively to maternal body mass index (R = 0.264, P = 0.021) and intrauterine glucose concentration (R = 0.736, P < 0.0001).

CONCLUSIONS

Physiologically relevant concentrations of AGE alter endometrial epithelial cell function. Antioxidants restore the rate of proliferation of AGE-treated endometrial epithelial (ECC-1) cells. Primary endometrial epithelial cells, cultured as organoids, demonstrate altered proliferation and CXCL16 secretion in the presence of AGE equimolar with the uterine fluid from obese individuals.

Clinical and laboratory parameters associated with pregnancy outcomes in patients undergoing frozen euploid blastocyst transfer

RESEARCH QUESTION

Which factors impact on clinical pregnancy rate (CPR) and live birth rates (LBR) in euploid frozen embryo transfer (eFET) cycles?

DESIGN

Retrospective observational study including 1660 eFET cycles with 2439 euploid blastocysts, from November 2016 to December 2020. The impact of clinical and laboratory parameters on CPR, biochemical miscarriage rate (BMR), clinical miscarriage rate (CMR) and LBR was evaluated.

RESULTS

CPR per transfer was 63.4%, LBR per transfer 51.6%. CPR and LBR were significantly higher when double embryo transfer (DET) was performed (71.6% versus 57.7%, P < 0.001; 55.2% versus 49.1%, P = 0.016, respectively). However, pregnancy loss was significantly higher in the DET group (28.8% versus 22.8%, P = 0.02). When patients were classified by body mass index (BMI), no differences were observed for CPR, but CMR was lower (P < 0.001) and LBR higher (p = 0.031) for the normal BMI group. The natural cycle protocol revealed lower CMR (P < 0.001) and lower pregnancy loss (P < 0.001); subsequently, higher LBR (57.6%, 48.8%, 45.0%, P = 0.001) compared with hormonal replacement protocol and stimulated cycle. Day of trophectoderm biopsy affected CPR (P < 0.001) and LBR (P < 0.001), yet no differences were observed for BMR, CMR or pregnancy loss. The multivariate analysis showed that day 6/7 embryos had lower probabilities for pregnancy; overweight and obesity had a negative impact on LBR, and natural cycle improved LBR (adjusted odds ratio 1.445, 95% confidence interval 0.519-0.806).

CONCLUSIONS

Day of biopsy affected CPR, while BMI and endometrial preparation protocol were associated with LBR in eFET. DET should be discouraged as it will increase the risk of pregnancy loss. Women with higher BMI should be aware of the higher risk of pregnancy loss and lower LBR even though a euploid blastocyst is transferred.

Prediction of risk factors for first trimester pregnancy loss in frozen-thawed good-quality embryo transfer cycles using machine learning algorithms

PURPOSE

Can the risk factors that cause first trimester pregnancy loss in good-quality frozen-thawed embryo transfer (FET) cycles be predicted using machine learning algorithms?

METHODS

This is a retrospective cohort study conducted at Sisli Memorial Hospital, ART and Reproductive Genetics Center, between January 2011 and May 2021. A total of 3805 good-quality FET cycles were included in the study. First trimester pregnancy loss rates were evaluated according to female age, paternal age, body mass index (BMI), diagnosis of infertility, endometrial preparation protocols (natural/artificial), embryo quality (top/good), presence of polycystic ovarian syndrome (PCOS), history of recurrent pregnancy loss (RPL), recurrent implantation failure (RIF), severe male infertility, adenomyosis and endometriosis.

RESULTS

The first trimester pregnancy loss rate was 18.2% (693/ 3805). The presence of RPL increased first trimester pregnancy loss (OR = 7.729, 95%CI = 5.908-10.142, P = 0.000). BMI, which is > 30, increased first trimester pregnancy loss compared to < 25 (OR = 1.418, 95%CI = 1.025-1.950, P = 0.033). Endometrial preparation with artificial cycle increased first trimester pregnancy loss compared to natural cycle (OR = 2.101, 95%CI = 1.630-2.723, P = 0.000). Female age, which is 35-37, increased first trimester pregnancy loss compared to < 30 (OR = 1.617, 95%CI = 1.120-2.316, P = 0.018), and female age, which is > 37, increased first trimester pregnancy loss compared to < 30 (OR = 2.286, 95%CI = 1.146-4,38, P = 0.016). The presence of PCOS increased first trimester pregnancy loss (OR = 1.693, 95%CI = 1.198-2.390, P = 0.002). The number of previous IVF cycles, which is > 3, increased first trimester pregnancy loss compared to < 3 (OR = 2.182, 95%CI = 1.708-2.790, P = 0.000).

CONCLUSIONS

History of RPL, RIF, advanced female age, presence of PCOS, and high BMI (> 30 kg/m2) were the factors that increased first trimester pregnancy loss.

The effect of maternal body mass index on embryo division timings in women undergoing in vitro fertilization

Objective

To measure the impact of maternal body mass index (BMI) on the morphokinetics of embryo development as monitored by a time-lapse system.

Design

A retrospective chart review of in vitro fertilization (IVF) cycles from September 2016 to January 2019.

Setting

Academic IVF practice.

Patients

Patients <age 38 years undergoing IVF with their own gametes.

Interventions

Not applicable.

Main outcome measures

The primary outcome was to compare embryo division timings between morbidly obese, obese, overweight, and normal-weight patients. A multilevel mixed effects model was performed to investigate the relationships between BMI categories and embryo division timings. Log or square transformation were used to improve fit.

Results

A total of 366 patients met inclusion criteria, yielding 4,475 embryos: 1,948 embryos from 162 normal-weight women (BMI 18.5-24.9), 1,242 embryos from 96 overweight women (BMI 25.0-29.9), 1,119 embryos from 91 obese women (BMI 30.0-39.9), and 166 embryos from 17 morbidly obese women (BMI ≥40). There were no differences in age, Antimüllerian hormone, or IVF cycle outcomes among the different BMI categories. When comparing embryo division timings based on BMI, controlling for covariates, embryos from obese patients had a shorter time to division to 2 cell embryo (T2) than normal-weight patients. When analyzing BMI as a continuous variable, there was no significant relationship between BMI and embryo division timing.

Conclusions

Early embryo divisions were accelerated in only certain categories of obesity. This suggests a more complex mechanism for the effect of obesity on embryo development that may not be perceptible through the assessment of cell division timing events.

BMI and miscarriage after IVF

PURPOSE OF REVIEW

To summarize recent findings related to the risk of miscarriage in women with elevated BMI undergoing IVF, and the mechanisms involved in said risk.

RECENT FINDINGS

Miscarriage rates are increased in overweight and obese women in both natural and assisted reproduction. Oocyte and embryo quality assessed according to classic morphological static parameters does not seem to be affected by excessive female body weight. Despite the initial lack of consensus between studies regarding embryo morphokinetics in obese women, blastocyst formation and quality have recently been shown to be similar across BMI groups, even in the case of euploid embryos. However, some metabolomic differences have been described in oocytes and embryos from obese women, thus pointing to a functional alteration. In women with elevated BMI, the percentage of aneuploid embryos is similar to that of normal weight women, and rates of miscarriage are higher, despite the transfer of euploid embryos. Therefore, the origin of the increased pregnancy loss rate after IVF in these women may be related to metabolomic, epigenetic or mitochondrial oocyte and embryo disturbances, or to the abnormal endocrine, metabolic and inflammatory uterine environment induced by obesity, which seems to be also responsible for other numerous complications during pregnancy and the in-utero fetal programming of postnatal diseases. A displacement of the window of implantation in obese women undergoing artificial endometrial preparation has recently been described and may be related to the poorer embryo implantation rates and increased risk of miscarriage observed following fresh and frozen embryo transfers with autologous oocytes, and with donated ova in recipients with extremely high BMI.

SUMMARY

Female obesity is related to poorer outcome in natural and assisted conception, including an increased risk of miscarriage. Embryo morphology, assessed by conventional methods or by morphokinetics, does not seem to be affected by excess weight, with similar blastocyst formation and quality than normal weight women reported in IVF cycles. Embryo aneuploidy is not increased, and higher miscarriages rates are seen after euploid embryo transfer in obese women. Disturbances of the uterus or its environment induced by female obesity seem to be the most likely cause of the increased risk of miscarriage, although metabolomic, epigenetic or mitochondrial oocyte and embryo dysfunction cannot be ruled out as cannot congenital anomalies. In the context of all the above, weight reduction before pregnancy should be advised in obese women trying to become pregnant.

Maternal body mass index is not associated with increased rates of maternal embryonic aneuploidy

OBJECTIVE

To evaluate the relationship between maternal body mass index (BMI) and embryonic aneuploidy of maternal origin.

DESIGN

Retrospective cohort analysis.

SETTING

University hospital-based reproductive center.

PATIENTS

Maternal origin of aneuploidy was available for 453 cycles and 1,717 embryos.

INTERVENTIONS

Data regarding BMI were collected before egg retrieval. Comparison groups included underweight (BMI, <18.5 kg/m²), normal weight (BMI, 18.5-24.9 kg/m²), overweight (BMI, 25-29.9 kg/m²), and obese (BMI, ≥30 kg/m²). Overall embryonic aneuploidy and maternal aneuploidy rates were compared. The aneuploidy rate was the number of embryos with either maternal or mixed (maternal and paternal) aneuploidy divided by the total number of embryos tested.

MAIN OUTCOME MEASURES

Overall embryonic aneuploidy and maternal aneuploidy rates.

RESULTS

Maternal aneuploidy rate was 51.5% for BMI of ≥30 kg/m² and 39.3% for BMI of <30 kg/m². Female age as well as several in vitro fertilization characteristics were significantly different across groups and were included in the adjusted model. Both the overall embryonic aneuploidy rate (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.11-1.59) and the maternal aneuploidy rate (OR, 1.64; 95% CI, 1.25-2.16) increased with increasing maternal BMI. However, after controlling for significant confounders, BMI did not significantly predict the rate of maternal aneuploidy (OR, 1.16; 95% CI, 0.85-1.59).

CONCLUSIONS

Maternal BMI did not correlate with embryonic aneuploidy of maternal origin after adjusting for confounders.

Association between clinical and IVF laboratory parameters and miscarriage after single euploid embryo transfers

BACKGROUND

The goal of this study was to investigate which factors, excluding embryo aneuploidies, are associated with miscarriage in patients who have undergone a single euploid blastocyst transfer.

METHODS

Retrospective, observational and multicenter study with 2832 patients undergoing preimplantational genetic testing for aneuploidies (PGT-A) due to repeated implantation failure, recurrent pregnancy loss, advanced maternal age or severe male factor were transferred one single euploid embryo.

RESULTS

One of the main findings was a significant relationship between body mass index (BMI) and miscarriage rates (13.4% in underweight women, 12.1% in normal weight, 14.5% in overweight, and 19.2% in obese women, odds ratio [OD] 1.04; 95% confidence interval [CI], 1.01-1.07 p = 0.006). Endometrial thickness (OD 0.65; 95%, 0.52-0.77 p = 0.04) and type of endometrial preparation (natural cycle or hormone replacement cycle) (OD 0.77; 95%, 0.52-0.77, p = 0.04) were also associated with miscarriage rates.

CONCLUSIONS

BMI was strongly associated to miscarriage rates. We also observed a weaker association with endometrial thickness and with the type of endometrial preparation (natural cycle or hormone replacement cycle). None of the other studied variables (biopsy day, maternal and male age, duration of infertility, cycle length, previous miscarriages, previous live births, previous In Vitro Fertilization (IVF) cycles, endometrial pattern and/or diagnosis) were associated with miscarriage rates.

Blastocyst formation is similar in obese and normal weight women: a morphokinetic study

STUDY QUESTION

Does the embryo cleavage pattern and rate of blastocyst formation differ between normal weight and obese women undergoing IVF?

SUMMARY ANSWER

Embryo morphokinetic development, final blastocyst formation rate and blastocyst morphology do not differ between obese and normal weight women.

WHAT IS KNOWN ALREADY

Female obesity has been related to impaired IVF outcomes. Although the mechanisms responsible for this detrimental effect are thought to include impaired oocyte and embryo quality and reduced endometrial receptivity, they are yet to be confirmed. Embryo quality has been commonly assessed using static morphological criteria. Only three studies have analysed the progress of embryos up to the blastocyst stage in women with elevated BMI, but they have used small samples of patients or have obtained contradictory results.

STUDY DESIGN, SIZE, DURATION

This retrospective, cohort study, was performed from January 2016 to May 2020. A total of 3316 ICSI cycles from 2822 women were included, of which 1251 cycles were part of a preimplantation genetic testing programme. In total, 17 848 embryos were analysed.

PARTICIPANTS/MATERIALS, SETTING, METHODS

This study reports on the IVF cycles of infertile women, with a known BMI, who underwent ICSI and whose embryos were grown until the fifth/sixth day of development in a time-lapse system. Patients were grouped as follows. Underweight was defined as a BMI <18.5 kg/m2; normal weight was a BMI of 18.5-24.9 kg/m2; overweight was a BMI of 25-29.9 kg/m2; and obesity was a BMI of ≥30 kg/m2. Embryo development was assessed on an external computer with analysis software.

MAIN RESULTS AND THE ROLE OF CHANCE

Despite an initial slower pattern of embryo development, the blastocyst formation rate on day 5 or on day 5 plus day 6 did not differ in obese women with respect to the other three BMI groups. Moreover, based on the evaluation of inner cell mass and the trophectoderm on both days of blastocyst development, embryo quality was similar across the BMI groups, as were the pattern of development and arrest up to blastocyst formation and the distribution of the categories of full, expanded and hatching blastocysts.

LIMITATIONS, REASONS FOR CAUTION

Limitations include the retrospective analysis of data, the use of BMI as the only parameter to define normal/abnormal female body weight, and the lack of complete information about clinical outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

Blastocyst formation and embryo morphokinetics are not affected by female obesity, and the poorer IVF outcomes described for such women are probably due to deficient endometrial receptivity. The role of endometrial progesterone exposure on the day of embryo transfer should be analysed in future studies as a possible determining factor.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was used and there are no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Maternal body mass index associates with blastocyst euploidy and live birth rates: the tip of an iceberg?

RESEARCH QUESTION

Does maternal preconceptional body mass index (BMI) associate with mean blastocyst euploidy rate (m-ER) per patient and live birth rate (LBR) after vitrified-warmed euploid single embryo transfer (SET)?

DESIGN

Observational study conducted between April 2013 and March 2020 at a private IVF clinic, involving 1811 Caucasian women undergoing trophectoderm biopsy and comprehensive chromosome testing. The outcomes of 1125 first vitrified-warmed euploid SET were also analysed. Patients were clustered as normal weight (BMI 18.5-25; n = 1392 performing 859 SET), underweight (BMI <18.5; n = 160 performing 112 SET) and overweight (BMI >25; n = 259 performing 154 SET). m-ER per patient was the primary outcome. The secondary outcomes were all clinical outcomes per euploid SET. All data were adjusted for confounders through regression analyses.

RESULTS

The m-ER per patient decreases as maternal BMI increases from 17 up to 22-23 before reaching a plateau. A linear regression adjusted for maternal age confirmed this moderate association (unstandardized coefficient B: -0.6%, 95% confidence interval [CI]: -1.1 to -0.1%, P = 0.02). All clinical outcomes were similar between normal weight and underweight women. Overweight women, instead, showed higher miscarriage rate per clinical pregnancy (n = 20/75, 26.7% versus n = 67/461, 14.5%; odds ratio [OR] adjusted for blastocyst quality and day of full blastulation: 2.0, 95% CI: 1.1-3.6, P = 0.01) and lower LBR per SET (n = 55/154, 35.7% versus n = 388/859, 45.2%; OR adjusted for blastocyst quality and day of full blastulation: 0.67, 95% CI: 0.46-0.96, P = 0.03).

CONCLUSION

These data indicate a need for future research on more sensitive metrics to assess body fat mass and distribution, as well as on the mechanisms leading to lipotoxicity, thereby impairing embryo competence and/or endometrial receptivity. Overweight women should be informed of their higher risk for miscarriage and, whenever possible, encouraged to lose weight, especially before transfer.

Influence of social determinants on fertility: a critical review

PURPOSE OF REVIEW

Intrinsic factors, such as age, weight and lifestyle habits, together with extrinsic factors, such as socioeconomic level, must be considered when it comes to reproductive healthcare. Over the last few years, studies that attempt to respond to the participation and interaction of these factors in subfertility have been published; however, some questions remain unanswered.

RECENT FINDINGS

Although there are little modifiable factors for women, it is possible to influence other factors, such as behavioural or cultural factors in order to minimize fertility problems; however, they are often highly influenced by each other.

SUMMARY

Advanced age, obesity, sedentary lifestyle, alcohol, tobacco and other compounds, have a clearly negative effect and may extend time-to-pregnancy, although the responsible mechanisms and the magnitude of the detriment that they produce in the reproductive health are yet to be studied. Economic context and new environmental factors are a current challenge for reproductive health too.

Body mass index is not associated with embryo ploidy in patients undergoing in vitro fertilization with preimplantation genetic testing

OBJECTIVE

To assess the association between body mass index (BMI) and embryo aneuploidy and mosaicism in a cohort of patients undergoing in vitro fertilization (IVF) with trophectoderm biopsy for preimplantation genetic testing for aneuploidy (PGT-A) using next-generation sequencing technology.

DESIGN

Retrospective cohort study.

SETTING

Academic center.

PATIENTS

Patients undergoing their first IVF cycle with trophectoderm biopsy and PGT-A at our center between January 1, 2017, and August 31, 2020. Patients classified as underweight on the basis of BMI (BMI <18.5 kg/m²) and patients who underwent fresh embryo transfers were excluded.

INTERVENTION

None.

MAIN OUTCOME MEASURES

Number and proportion of aneuploid, mosaic, and euploid embryos.

RESULTS

The patients were stratified according to the World Health Organization's BMI classification: normal weight (18.5-24.9 kg/m², n = 1,254), overweight (25-29.9 kg/m², n = 351), and obese (≥30 kg/m², n = 145). Age-adjusted regression models showed no relationship between BMI classification and the number or proportion of aneuploid embryos. There were no statistically significant associations between BMI classifications and the number or proportion of mosaic or euploid embryos. A subgroup analysis of patients classified into age groups of <35, 35-40, and >40 years similarly showed no relationships between BMI and embryo ploidy outcomes.

CONCLUSION

Body mass index was not associated with the number or proportion of aneuploid, mosaic, or euploid embryos in this large cohort of patients undergoing IVF with PGT-A, suggesting that the negative effect of excess weight on reproductive outcomes was independent of the ploidy status of the embryo cohort.

Which factors affect the likelihood of miscarriage after single euploid blastocyst transfer?

RESEARCH QUESTION

Which parameters affect the likelihood of miscarriage after single euploid frozen-thawed blastocyst transfer (FBT)?

DESIGN

In this retrospective study, clinical and laboratory data from 1051 single euploid FBTs were evaluated. Exclusion criteria were endocrine or systemic pathologies, uterine anomalies or pathologies, unilateral or bilateral hydrosalpinx, karyotypic abnormalities (either maternal or paternal) or thrombophilia. Patients were divided into two groups according to pregnancy outcome: live birth and miscarriage.

RESULTS

Body mass index (BMI) (25.98 ± 0.5 versus 24.36 ± 0.21, P = 0.019), duration of infertility (6.62 ± 0.54 versus 4.92 ± 0.18, P = 0.006) and number of previous miscarriages (1.36 ± 0.13 versus 0.79 ± 0.05, P < 0.001) were significantly higher in the miscarriage group (n = 100) than in the live birth group (n = 589). Although the trophectoderm and inner cell mass (ICM) percentage scores were not statistically different among the miscarriage and live birth groups, the percentage of day-6 biopsied embryos was significantly higher in the miscarriage group. Binary logistic regression analysis revealed that BMI (OR 1.083, 95% CI 1.013 to 1.158, P = 0.02) and number of previous miscarriages (OR 1.279, 95% CI 1.013 to 1.158, P = 0.038) were independent factors for miscarriage. Patients with elevated BMI and a higher number of miscarriages were at increased risk of miscarriage.

CONCLUSION

After a single euploid FBT, BMI and number of previous miscarriages are predictors of miscarriage. Lifestyle interventions before FBT may decrease miscarriage rates.

Female obesity increases the risk of miscarriage of euploid embryos

OBJECTIVE

To determine whether female body mass index (BMI) is associated with an increased risk of miscarriage after euploid embryo transfer.

DESIGN

A retrospective, observational, multicenter cohort study.

SETTING

University-affiliated in vitro fertilization center.

PATIENT(S)

In this study, 3,480 cycles of in vitro fertilization with preimplantation genetic testing for aneuploidy (PGT-A) in the blastocyst stage and euploid embryo transfer were divided into four groups according to patient BMI.

INTERVENTION(S)

In vitro fertilization with PGT-A.

MAIN OUTCOME MEASURE(S)

The primary outcome was the miscarriage rate, which included both biochemical and clinical miscarriages. Secondary outcomes were implantation, pregnancy, clinical pregnancy, and live birth rates.

RESULT(S)

Cycles were divided into four groups according to BMI (kg/m²): underweight (<18.5; n = 155), normal weight (18.5-24.9; n = 2,549), overweight (25-29.9; n = 591), and obese (≥30; n = 185). The number of PGT-A cycles per patient was similar in the four groups. Fertilization rate, day of embryo biopsy, technique of chromosomal analysis, number of euploid embryos, number of transferred embryos, and method of endometrial preparation for embryo transfer were similar in the four BMI groups. Miscarriage rates were significantly higher in women with obesity compared to women with normal weight, mainly due to a significant increase in the clinical miscarriage rates. Live birth rates also were lower in women with obesity. Obesity in women and day 6 trophectoderm biopsy were found to influence the reduced live birth rate.

CONCLUSION(S)

Women with obesity experience a higher rate of miscarriage after euploid embryo transfer than women with a normal weight, suggesting that other mechanisms than aneuploidy are responsible for this outcome.

Can embryo morphokinetic parameters predict euploid pregnancy loss?

OBJECTIVE

To use time-lapse imaging to compare embryo morphokinetic parameters between embryos resulting in euploid pregnancy loss and euploid embryos resulting in live birth.

DESIGN

Retrospective cohort study.

SETTING

Single academic fertility center.

PATIENT(S)

All euploid single embryo transfers between October 2015 and January 2018.

INTERVENTION(S)

Collection and analysis of baseline characteristics, cycle parameters, and outcomes.

MAIN OUTCOME MEASURE(S)

Embryo morphokinetic measurements assessed with time-lapse imaging for time to syngamy (TPNf), time to two cells, time to three cells, time to four cells, time to eight cells, time to morula, and time to blastocyst.

RESULT(S)

The study included 192 euploid single-embryo transfers. Of these, the pregnancy rate was 78% (150 of 193) and the live-birth rate was 63% (121 of 193). There were 43 transfers that did not result in pregnancy, 15 biochemical pregnancy losses, 13 clinical losses, and 121 live births. There was no statistically significant difference in age, body mass index, or number of oocytes retrieved between the groups. Unadjusted and adjusted models revealed no differences in the morphokinetics of embryos resulting in euploid miscarriage compared with those resulting in live birth.

CONCLUSION(S)

Embryos that resulted in a euploid miscarriage did not display evidence of abnormal morphokinetics on time-lapse imaging. Euploid pregnancy loss is likely multifactorial, including both embryo and endometrial factors. Further research is needed to identify factors that can predict and prevent euploid loss.

Advanced glycation end products present in the obese uterine environment compromise preimplantation embryo development

RESEARCH QUESTION

Proinflammatory advanced glycation end products (AGE), highly elevated within the uterine cavity of obese women, compromise endometrial function. Do AGE also impact preimplantation embryo development and function?

DESIGN

Mouse embryos were cultured in AGE equimolar to uterine fluid concentrations in lean (1-2 µmol/l) or obese (4-8 µmol/l) women. Differential nuclear staining identified cell allocation to inner cell mass (ICM) and trophectoderm (TE) (day 4 and 5 of culture). Cell apoptosis was examined by terminal deoxynucleotidyl transferase-mediated dUDP nick-end labelling assay (day 5). Day 4 embryos were placed on bovine serum albumin/fibronectin-coated plates and embryo outgrowth assessed 93 h later as a marker of implantation potential. AGE effects on cell lineage allocation were reassessed following pharmacological interventions: either 12.5 nmol/l AGE receptor (RAGE) antagonist; 0.1 nmol/l metformin; or combination of 10 µmol/l acetyl-l-carnitine, 10 µmol/l N-acetyl-l-cysteine, and 5 µmol/l alpha-lipoic acid.

RESULTS

8 µmol/l AGE reduced: hatching rates (day 5, P < 0.01); total cell number (days 4, 5, P < 0.01); TE cell number (day 5, P < 0.01), and embryo outgrowth (P < 0.01). RAGE antagonism improved day 5 TE cell number.

CONCLUSIONS

AGE equimolar with the obese uterine environment detrimentally impact preimplantation embryo development. In natural cycles, prolonged exposure to AGE may developmentally compromise embryos, whereas following assisted reproductive technology cycles, placement of a high-quality embryo into an adverse 'high AGE' environment may impede implantation success. The modest impact of short-term RAGE antagonism on improving embryo outcomes indicates preconception AGE reduction via pharmacological or dietary intervention may improve reproductive outcomes for overweight/obese women.

Measuring serum estradiol and progesterone one day prior to frozen embryo transfer improves live birth rates

BACKGROUND

Given no consensus in the literature, this study sought to determine if a protocol of measuring serum estradiol and progesterone the day prior to frozen embryo transfer (FET) improves likelihood of pregnancy and livebirth.

METHODS

This was a retrospective time-series study of women undergoing autologous vitrified-warmed blastocyst programmed FETs at an academic institution. Live birth rates were compared between a surveillance protocol, where serum estrogen and progesterone surveillance are performed the day prior to a programmed FET, and a standard protocol, whereby no hormonal lab evaluation is performed the day prior.

RESULTS

Three hundred seventy-nine standard FET and 524 surveillance FET cycles were performed. Patients in the surveillance protocol were significantly more likely to achieve live birth (51% vs. 39%; aOR 1.6, 95%CI [1.2, 2.2]). Obese women were noted to be more likely to have lower progesterone hormone levels on surveillance labs (OR 3.2, 95%CI [2.0, 5.3]). However those whose hormonal medication dose was modified because of pre-transfer labs were as likely to achieve live birth as those whose dose was not modified (47% vs. 53%; aOR 0.8, 95%CI [0.6, 1.2]).

CONCLUSIONS

Cycles with the surveillance protocol were more likely to result in live birth. Patients with low levels of pre-transfer hormones, such as obese patients, likely have lower pregnancy rates. It is possible that when these levels were corrected after measurement, pregnancy rates improved to match those whose levels were not low enough to warrant intervention.

Parameters impacting the live birth rate per transfer after frozen single euploid blastocyst transfer

Background

To assess the predictive value of patient characteristics, controlled ovarian stimulation and embryological parameters on the live birth outcome of single euploid frozen-warmed blastocyst transfer (FBT).

Methods

This was a retrospective cohort study including 707 single FBTs after preimplantation genetic testing for aneuploidy (PGT-A) that were performed from October 1, 2015, to January 1, 2018. The effects of patient-, cycle- and embryology-related parameters on the live birth outcome after FBT were assessed.

Results

In the subgroup analysis based on live birth, patients who achieved a live birth had a significantly lower body mass index (BMI) than patients who did not achieve a live birth (22.7 (21.5–24.6) kg/m² vs 27 (24–29.2) kg/m², p<0.001). The percentage of blastocysts with inner cell mass (ICM) A or B was significantly higher among patients achieving a live birth, at 91.6% vs. 82.6% (p<0.001). Day-5 biopsies were also more prevalent among patients achieving a live birth, at 82.9% vs 68.1% (p<0.001). On the other hand, the mitochondrial DNA (mtDNA) levels were significantly lower among cases with a successful live birth, at 18.7 (15.45–23.68) vs 20.55 (16.43–25.22) (p = 0.001). The logistic regression analysis showed that BMI (p<0.001, OR: 0.789, 95% CI [0.734–0.848]), day of trophectoderm (TE) biopsy (p<0.001, OR: 0.336, 95% CI [0.189–0.598]) and number of previous miscarriages (p = 0.004, OR: 0.733, 95% CI [0.594–0.906]) were significantly correlated with live birth. Patients with elevated BMIs, cycles in which embryos were biopsied on day-6 and a higher number of miscarriages were at increased risks of reduced live birth rates.

Conclusion

A high BMI, an embryo biopsy on day-6 and a high number of miscarriages negatively affect the live birth rate after single euploid FBT.

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 (E₂) 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.

Risk factors and role of low molecular weight heparin in obstetric complications among women with inherited thrombophilia - a cohort study

Introduction

Although there is a vast literature regarding the association between inherited thrombophilia, obstetric complications and the effect of low molecular weight heparin (LMWH), these are controversial and we have not found publications related to additional risk factors other than thrombophilia.

Our objectives were to assess the prevalence of miscarriage, placenta-mediated pregnancy complications and fetal loss in pregnant women with IT, establishing associated risk factors and the effect of LMWH.

Materials and methods

A retrospective cohort of pregnant women with IT was formed. Risk factors considered were: high-risk IT, age ≥35 years, body mass index ≥25 and ≥30, assisted reproductive technology, antiphospholipid antibodies, autoimmune disease, first-degree family history of obstetric complications and personal history of venous or arterial thromboembolic disease, the outcomes being M, FL and PMPC.

Results and conclusions

Data from 250 pregnancies in 88 women were obtained.

There were 112 (45%) Ms, 13 (5.2%) FLs and 25 (10%) PMPCs.

High-risk IT was associated with FL (OR = 4.96; 95% CI, 1.42–17.3). Antiphospholipid antibodies and family history of obstetric complications were associated with PMPC (OR = 7.12; 95% CI, 1.89–26.74, OR = 3.88; 95% CI, 1.18–12.78, respectively). The LMWH presented a benefit in the combined outcome (any obstetric complication, OR = 0.25; 95% CI, 0.12–0.54) and M (OR = 0.41; 95% CI, 0.20–0.82).

We conclude that obstetric complications are common in women with IT. Antiphospholipid antibodies, family history of obstetric complications and high-risk IT might be additional risk factors. The LMWH has an apparent protective effect against obstetric complications, which is consistent with some previous studies.

Increased body mass index associated with increased preterm delivery in frozen embryo transfers

The present study was performed to investigate whether maternal body mass index (BMI) affected the live birth (LB) outcomes of frozen embryo transfers (FET) in patients who underwent freeze-all treatment cycles. The autologous intracytoplasmic sperm injection (ICSI) cycles with blastocyst freeze-all cycles performed between February 2015 and January 2016 were retrospectively investigated. The 1188 subsequent FET performed were grouped according to maternal BMI classes for analysis; underweight (<18.5 kg/m²; 3.5%), normal-weight (18.5-24.9 kg/m²; 40.1%), overweight (25.0-29.9 kg/m²; 33.7%), or obese (classes I-III; ≥30.0 kg/m²; 22.8%). Uni- and multivariate analyses were performed, with LB as the primary outcome measure. In the categorical analyses of only the single blastocyst transfers (SBT), positive pregnancy (PP), LB and total pregnancy loss (totPL) rates were similar in the maternal BMI classes; however, the preterm delivery (PTD) rate in the obese class was significantly higher. In the multiple logistic regression models, maternal age was the most significant predictor of LB (OR = 0.9, 95%CI (0.90-0.98), p = .006) and the maternal BMI was the most significant predictor of PTD (OR = 1.1, 95% CI (1.02-1.14), p = .010). In conclusion, maternal BMI was the most significant variable in the outcome of PTD, with obese female patients at an increased risk of PTD. Impact statement What is known already? Obesity is rising worldwide to epidemic proportions and is expected to continue rising in the foreseeable future. Overweight and obesity not only increases the morbidity and mortality in the female populations but also significantly increases the risks of infertility in the women of reproductive age. Body mass index (BMI) has been the most widely used measure to describe the body weight of infertile patients. What do the results of this study add? Underweight, overweight and obesity do not significantly contribute to live birth outcomes. Maternal BMI was a significant predictor of PTD, with obesity most significantly at risk of PTD. What are the implications of these findings for clinical practice and/or further research? The evidence suggests that the weight management policy remain unchanged in IVF practice, with weight loss recommended for both young and ageing infertile patients. Performing a 'therapeutic' freeze-all IVF in the patients with weight-associated infertility may be a more suitable treatment strategy.

Effects of maternal body mass index on pregnancy outcome after 8570 artificial insemination cycles with donor's sperm

Increased body mass index (BMI) might have an adverse effect on pregnancy. However, the influence of BMI on the pregnancy outcomes after artificial insemination with donor's sperm (AID) had been rarely reported. This study aimed to investigate the correlation between BMI and AID. The pregnancy outcome of 8570 AID cycles was retrospectively analyzed. BMI was categorized as underweight (<18.5 kg/m²; group A), normal weight (18.5-23.9 kg/m²; group B), overweight (24-27.9 kg/m²; group C), and obese (≥28 kg/m²; group D). The results showed that cumulative pregnancy rate and cumulative live birth rate in groups A, B, C and D tended to decrease as BMI increased; however, abortion rate, and ectopic pregnancy rate in groups A, B, C, and D exhibited a gradual increase in the tendency. Cesarean delivery rate also increased as BMI increased. Birth defect rate in the group D were significantly higher than that in the group A. Interestingly, the pregnancy rate was gradually decreased with increasing age in groups A, B, and C, but this was not observed in the group D. The findings suggested that BMI can affect the pregnancy outcomes after AID; it is important to achieve a normal BMI prior to AID treatments.

The effect of female body mass index on in vitro fertilization cycle outcomes: a multi-center analysis

PURPOSE

The aim of this study is to examine the impact of female body mass index (BMI) on IVF cycle outcomes.

METHODS

This is a retrospective cohort study including 51,198 women who initiated their first autologous IVF cycle in 13 fertility centers in the USA between 2009 and 2015. The effect of underweight, overweight, and obese BMI on four different IVF cycle outcomes (cycle cancellation, oocyte and embryo counts, and ongoing clinical pregnancy [OCP]) was evaluated in logistic or Poisson regression analyses with confounders adjusted.

RESULTS

Women with an overweight or obese BMI experienced worse outcomes than those with a normal BMI. These differences included (1) greater odds of cycle cancellation (aOR [95%CI] 1.17 [1.08, 1.26] for overweight, 1.28 [1.15, 1.41] for class-I obesity, and 1.50 [1.33, 1.68] for class-II/III obesity, P < .001 for all); (2) fewer oocytes retrieved (aIRR [95%CI] 0.98 [0.98,0.99] for class-I obesity, 0.93 [0.92,0.94] for class-II/III obesity, P < .001 for both); (3) fewer usable embryos (aIRR [95%CI] 0.98 [0.97,0.99] for overweight, 0.97 [0.96,0.99] for class-I obesity, 0.95 [0.93,0.97] for class-II/III obesity, P < .01 for all); and (4) lower odds of OCP (aOR [95%CI] 0.89 [0.83,0.95] for class-I obesity, 0.86 [0.79,0.93] for class-II/III obesity, P < .001 for both). In a subgroup analysis based on primary infertility diagnosis, these trends persisted in those with male or uterine factor and were especially pronounced in women with ovulatory dysfunction or PCOS.

CONCLUSIONS

A BMI above the normal range was an independent negative prognostic factor for multiple outcomes, including cycle cancellation, oocyte and embryo counts, and OCP. These negative outcomes were most profound in women with class-II/III obesity, ovulatory dysfunction, or PCOS.

High Body Mass Index is associated with an expansion of endometrial T Regulatory cell and macrophage populations

Obesity is associated with implantation failure, miscarriage, low-grade inflammation and a reduction in peripheral immune-suppressive T regulatory (Treg) cells. Therefore, we postulated that this reduction may also extend to the endometrium and cause embryonic loss. In a cohort of 40 infertile women, without implantation failure or recurrent miscarriage, we examined the density of Treg cells, macrophages and natural killer (NK) cells in mid-luteal endometrial biopsies. Significant positive correlations were observed between BMI and endometrial Treg cells and macrophages, but no relationship with NK cells. We postulate that this change may be a positive adaption to minimise adiposity related inflammation.

The rate of euploid miscarriage is increased in the setting of adenomyosis

STUDY QUESTION

Does the rate of miscarriage increase in the setting of adenomyosis independent of other known risk factors for miscarriage such as maternal age, BMI, embryo genetic status?

SUMMARY ANSWER

Adenomyosis and high BMI both significantly increase miscarriage risk independent of each other, maternal age and embryo health. This study is the first to suggest that ultra-long down regulation GnRH agonist treatment may reduce the rate of early pregnancy loss in adenomyosis patients.

WHAT IS KNOWN ALREADY

The presence of adenomyosis is known to be associated with lower rates of successful implantation and increased risk of early pregnancy loss. However, it is presently unclear whether this reproductive impairment is directly mediated by adenomyosis itself, or indirectly caused by adenomyosis association with known risk factors for miscarriage such as obesity and advancing maternal age/foetal aneuploidy.

STUDY DESIGN SIZE DURATION

A retrospective cohort study was undertaken in a private infertility (IVF) clinic examining the outcome for women (n = 345) undergoing the transfer of a genetically screened frozen-thawed embryo between 2012 and 2015.

PARTICIPANTS/MATERIALS SETTING AND METHOD

A total of 171 women who successfully conceived (positive serum βhCG) following the transfer of a single euploid good morphology frozen-thawed embryo were included in analysis after meeting the inclusion criteria. Only the first conception cycle for each patient was included in the study. Patients with known pre-existing medical risk factors for miscarriage (e.g. thrombophilia, poorly controlled diabetes, coeliac disease, SLE, uterine septum, chromosomal abnormalities) and those women undergoing treatment using donated oocytes and surrogacy were excluded. Patients were then classified as having adenomyosis or not based on a high-quality pelvic ultrasound or MRI. The direct and indirect effects of adenomyosis and BMI on overall miscarriage rate by 12 weeks gestation was then assessed using multivariate logistic regression and mediation analysis. Furthermore, the data were also analysed to elucidate the influence of GnRH ultra-long down-regulation therapy on miscarriage rates.

MAIN RESULTS AND ROLE OF CHANCE

Overall, the adjusted rate of miscarriage was higher in those patients with adenomyosis compared to those without (44.1 vs 15.3%, P < 0.0001), with most of these miscarriages occurring at the early biochemical stage. The rate of miscarriage was especially high in adenomyosis patients not receiving GnRH agonist pre-treatment (82.4%), compared to those patients who did receive GnRH pre-treatment (35.7%, P = 0.0089).

LIMITATIONS REASONS FOR CAUTION

The study is mainly limited by its small sample size and retrospective design which carries inherent potential for bias (i.e. misclassification and errors due to inadequate clinical notes). The small sample size precluded analysis to distinguish how the extent of adenomyosis disease may modify miscarriage risk (i.e. focal or diffuse disease). Furthermore, the relatively low number of adenomyosis patients not receiving GnRH agonist treatment, plus the non-randomized nature of the decision not to offer such treatment, precludes definitive conclusions on the benefit of GnRH agonist therapy to reduce miscarriage risk.

WIDER IMPLICATIONS OF THE FINDINGS

Considering the significant emotional and financial impact of miscarriage, we suggest screening of all women undergoing IVF treatment for the presence of adenomyosis, with consideration given to ultra-long down regulation GnRH agonist treatment in any woman identified as having adenomyosis. Furthermore, given the persistent and often progressive nature of the disease, adenomyosis should also be considered as a potential uterine cause of recurrent miscarriage. Finally, we hope our study highlights the need for high-quality prospective RCT to be undertaken to provide superior evidence for the potential benefit of GnRH agonist pre-treatment.

STUDY FUNDING/COMPETING INTERESTS

K.T. is a practicing IVF gynaecologist and holds a minority stake in the publicly listed company Monash IVF. The other authors declare that they have no conflict of interest. This study was financially supported by Flinders University Medical School.

Promoting healthy lifestyle in fertility clinics; an Australian perspective

STUDY QUESTION

Are Australian fertility clinics adequately addressing unhealthy lifestyle in patients seeking fertility treatment?

SUMMARY ANSWER

This study has highlighted deficiencies in practices and education around managing patients with unhealthy lifestyle undergoing fertility treatment.

WHAT IS KNOWN ALREADY

The association between lifestyle and fertility is well documented, with obesity and smoking being of particular concern to fertility and pregnancy outcomes. Guidelines recommend that unhealthy lifestyle is addressed prior to conception, yet anecdotal experience suggests this is not being addressed. Lifestyle modification programmes can be effective in improving pregnancy rates and outcomes, however, recruitment to such programmes can be challenging.

STUDY DESIGN SIZE, DURATION

A cohort study of Australian fertility clinics’ attitudes and practices regarding lifestyle modification to augment reproductive treatment outcomes was conducted between August and October 2015.

PARTICIPANTS/MATERIALS, SETTING, METHOD

An online survey was administered to senior fertility nurses, from all registered fertility clinics in Australia. Data were collated and subjected to a univariate data analysis, where frequency tables were produced for each question. A separate qualitative analysis was undertaken of data from open ended questions.

MAIN RESULTS AND THE ROLE OF CHANCE

Fifty-three out of 85 potential respondents (62.4%), all from different clincis, completed the survey, with almost all acknowledging the importance of addressing unhealthy lifestyle before offering ART treatment. However, most clinics did not offer internal resources to assist with lifestyle modification. Whilst the promotion of healthy lifestyle was recognised as a key component of the role of a fertility nurse, participants did not feel that nurses were best equipped to provide lifestyle modification programmes, owing to a lack of resources and specific skills in this area. Suggested areas for improved practice included prioritising general health prior to offering treatment, and further utilising and upskilling nurses to assist with lifestyle modification programmes.

LIMITATIONS REASONS FOR CAUTION

The survey was completed by only one nurse from each clinic and as such may not be entirely representative of all clinic practices.

WIDER IMPLICATIONS OF THE FINDINGS

Fertility clinics are likely to see an increasing number of patients with unhealthy lifestyle, resulting in health concerns such as obesity. The results of this study provide an insight into how unhealthy lifestyle is currently being addressed in fertility clinics and suggested areas that could be targeted for improving practice and outcomes.

STUDY FUNDING/COMPETING INTERESTS

No conflict of interest to declare. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

TRIAL REGISTRATION NUMBER

NA

Duration of blastulation may be associated with ongoing pregnancy rate in single euploid blastocyst transfer cycles

Not all euploid embryos implant, necessitating additional tools to select viable blastocysts in preimplantation genetic screening cycles. In this retrospective cohort study, 129 consecutive patients who underwent 129 single euploid blastocyst transfers in cryopreserved embryo transfer cycles were included. All embryos were individually cultured in a time-lapse incubator from intracytoplasmic sperm injection up to trophoectoderm biopsy. Twenty-three time-lapse morphokinetic variables were tested among patients with (n = 68) or without (n = 61) ongoing pregnancy. All 23 time-lapse morphokinetic variables, apart from duration of blastulation (tB-tSB), were comparable between patients with or without ongoing pregnancy. Duration of blastulation was significantly shorter in patients with ongoing pregnancy (8.1 ± 3.2 versus 9.5 ± 3.4 h; P = 0.014); shorter duration of blastulation remained an independent predictor for ongoing pregnancy, when tested by logistic regression analysis (OR 0.81; 95% CI 0.70 to 0.93). One important limitation of this study, and a reason for caution, is the use of multiple comparisons, which can lead to differences at the 0.05 level simply by chance or random variation. Nonetheless, the study suggests that when more than one euploid blastocyst is available, priority might be given to those with a shorter duration of blastulation.

Genetic and hemostasiological predictors of IVF pregnancy

The performed clinical laboratory and instrumental research involved 93 pregnant women after IVF: 36 with progressive pregnancy and 57 women with missed abortion at term 6-8 weeks. The following parameters were evaluated: family history of thrombosis, menstrual function, gynecological and other diseases, duration of infertility treatment, pelvic organs sonography, hemostasis evaluation and thrombophilia genes investigation. The association of polymorphic allele 455 A of gene FGB with the risk of nondeveloping pregnancy after IVF was revealed. The genotype presence of allele 455 A of gene FGB increases the risk of miscarriage after IVF. The research has also revealed the association of polymorphic allele 4 G of gene PAI-1 in polymorphic locus 675:4 G/5 G with the risk of miscarriage. The received data on hemostatic system at an early term of pregnancy after IVF demonstrate enough stability and consistent thrombocytic and coagulative hemostasis of all examined women. Patients with progressive pregnancy have a considerably lower level of platelets than the patients with miscarriage. The average content of fibrinogen in women with progressive pregnancy is considerably higher than that in the patients in other groups. APTT is positively higher in patients of group A. The average content of SFMC in patients of group A was positively higher. The patients with non-developing pregnancy after IVF showed a considerably lower SFMC content.