Is Embryo Cryopreservation Causing Macrosomia-and What Else?

Association between frozen embryo transfer and childhood allergy: a retrospective cohort study

RESEARCH QUESTION

Does frozen embryo transfer (FET) increase the risk of allergic diseases in offspring?

DESIGN

This study followed up 653 singleton children: 166 born through FET and 487 born through natural conception. Demographic characteristics, perinatal information and allergic diseases of children and their parents were collected through clinical medical systems and questionnaires. Among these 653 children, allergen-specific immunoglobulin E (IgE) testing was performed using peripheral blood samples collected from 207 children: 145 in the FET group and 62 in the natural conception group. The prevalence of allergic diseases and positive rates of allergen-specific IgE testing were compared between the two groups with adjustments for confounding factors.

RESULTS

The prevalence of food allergy was significantly higher in children born through FET compared with children born through natural conception (adjusted OR = 3.154, 95% CI 1.895-5.250; P < 0.001). In addition, positive rates of food allergen sensitization were higher in children in the FET group compared with children in the natural conception group (adjusted OR = 5.769, 95% CI 2.859-11.751, P < 0.001). Children in the FET group had a higher positive sensitization rate to at least one allergen compared with children in the natural conception group (adjusted OR = 3.127, 95% CI 1.640-5.961, P < 0.001). No association was observed between FET and other allergic diseases, including asthma (P = 0.136), atopic dermatitis (P = 0.130) and allergic rhinitis (P = 0.922). Allergen sensitization IgE testing indicated no differences between the two groups in terms of positive sensitization rates of other common allergens, including animal and insect allergens (P = 0.627), inhaled outdoor allergens (P = 0.915) and inhaled outdoor allergens (P = 0.544).

CONCLUSION

This study suggests that children born through FET have increased risk of developing food allergy in early childhood.

hMG addition affects the change in progesterone level during IVF stimulation and LBR: a retrospective cohort study

BACKGROUND

Premature progesterone (P) rise during IVF stimulation reduces endometrial receptivity and is associated with lower pregnancy rates following embryo transfer (ET), which can influence provider recommendation for fresh or frozen ET. This study aimed to determine whether change in P level between in IVF baseline and trigger (𝚫P) is predictive of pregnancy outcome following fresh ET, and whether the ratio of gonadotropins influences P rise and, as a result, clinical pregnancy outcomes: clinical pregnancy rate (CPR) and live birth rates (LBR).

METHODS

Retrospective cohort study at a single fertility center at an academic institution. The peak P level and 𝚫P were modeled in relation to prediction of CPR and LBR, and the ratios of hMG:rFSH were also modeled in relation to prediction of peak P level on day of trigger, 𝚫P, and CPR/LBR in a total of 291 patients undergoing fresh embryo transfer after controlled ovarian hyperstimulation-IVF (COH-IVF).

RESULTS

𝚫P correlates with CPR, with the most predictive range for success as 𝚫P 0.7-0.85 ng/mL (p = 0.005, 95% CI 0.635, 3.636; predicting CPR of 88.9%). The optimal range for peak P in regard to pregnancy outcome was 0.15-1.349 ng/mL (p = 0.01; 95% CI for coefficient in model 0.48-3.570). A multivariable logistic model for prediction of CPR and LBR using either peak or 𝚫P supported a stronger association between 𝚫P and CPR/LBR as compared to peak P. Furthermore, an hMG:rFSH ratio of > 0.6 was predictive of lowest peak P (p = 0.010, 95% CI 0.035, 0.256) and smallest 𝚫P (p = 0.012, 95% CI 0.030, 0.243) during COH-IVF cycles. Highest CPRs were observed within hMG:rFSH ratios of 0.3-0.4 [75.6% vs. 62.5% within and outside of the range, respectively, (p = 0.023, 95% CI 0.119, 1.618)]. Highest LBRs were seen within the range of 0.3-0.6 hMG:rFSH, [LBR of 55.4% vs. 41.4% (p = 0.010, 95% CI 0.176, 1.311)].

CONCLUSIONS

Our data supports use of 𝚫P to best predict pregnancy rates and therefore can improve clinical decision making as to when fresh ET is most appropriate. Furthermore, we found optimal gonadotropin ratios can be considered to minimize P rise and to optimize CPR/LBR, emphasizing the importance of luteinizing hormone (LH) activity in COH-IVF cycles.

No major differences in perinatal and maternal outcomes between uninterrupted embryo culture in time-lapse system and conventional embryo culture

STUDY QUESTION

Is embryo culture in a closed time-lapse system associated with any differences in perinatal and maternal outcomes in comparison to conventional culture and spontaneous conception?

SUMMARY ANSWER

There were no significant differences between time-lapse and conventional embryo culture in preterm birth (PTB, <37 weeks), low birth weight (LBW, >2500 g) and hypertensive disorders of pregnancy for singleton deliveries, the primary outcomes of this study.

WHAT IS KNOWN ALREADY

Evidence from prospective trials evaluating the safety of time-lapse incubation for clinical use show similar embryo development rates, implantation rates, and ongoing pregnancy and live birth rates when compared to conventional incubation. Few studies have investigated if uninterrupted culture can alter risks of adverse perinatal outcomes presently associated with IVF when compared to conventional culture and spontaneous conceptions.

STUDY DESIGN, SIZE, DURATION

This study is a Swedish population-based retrospective registry study, including 7379 singleton deliveries after fresh embryo transfer between 2013 and 2018 from selected IVF clinics. Perinatal outcomes of singletons born from time-lapse-cultured embryos were compared to singletons from embryos cultured in conventional incubators and 71 300 singletons from spontaneous conceptions. Main perinatal outcomes included PTB and LBW. Main maternal outcomes included hypertensive disorders of pregnancy (pregnancy hypertension and preeclampsia).

PARTICIPANTS/MATERIALS, SETTING, METHODS

From nine IVF clinics, 2683 singletons born after fresh embryo transfer in a time-lapse system were compared to 4696 singletons born after culture in a conventional incubator and 71 300 singletons born after spontaneous conception matched for year of birth, parity, and maternal age. Patient and treatment characteristics from IVF deliveries were cross-linked with the Swedish Medical Birth Register, Register of Birth Defects, National Patient Register and Statistics Sweden. Children born after sperm and oocyte donation cycles and after Preimplantation Genetic testing cycles were excluded. Odds ratio (OR) and adjusted OR were calculated, adjusting for relevant confounders.

MAIN RESULTS AND THE ROLE OF CHANCE

In the adjusted analyses, no significant differences were found for risk of PTB (adjusted OR 1.11, 95% CI 0.87-1.41) and LBW (adjusted OR 0.86, 95% CI 0.66-1.14) or hypertensive disorders of pregnancy; preeclampsia and hypertension (adjusted OR 0.99, 95% CI 0.67-1.45 and adjusted OR 0.98, 95% CI 0.62-1.53, respectively) between time-lapse and conventional incubation systems. A significantly increased risk of PTB (adjusted OR 1.31, 95% CI 1.08-1.60) and LBW (adjusted OR 1.36, 95% CI 1.08-1.72) was found for singletons born after time-lapse incubation compared to singletons born after spontaneous conceptions. In addition, a lower risk for pregnancy hypertension (adjusted OR 0.72 95% CI 0.53-0.99) but no significant difference for preeclampsia (adjusted OR 0.87, 95% CI 0.68-1.12) was found compared to spontaneous conceptions. Subgroup analyses showed that some risks were related to the day of embryo transfer, with more adverse outcomes after blastocyst transfer in comparison to cleavage stage transfer.

LIMITATIONS, REASONS FOR CAUTION

This study is retrospective in design and different clinical strategies may have been used to select specific patient groups for time-lapse versus conventional incubation. The number of patients is limited and larger datasets are required to obtain more precise estimates and adjust for possible effect of additional embryo culture variables.

WIDER IMPLICATIONS OF THE FINDINGS

Embryo culture in time-lapse systems is not associated with major differences in perinatal and maternal outcomes, compared to conventional embryo culture, suggesting that this technology is an acceptable alternative for embryo incubation.

STUDY FUNDING/COMPETING INTEREST(S)

The study was financed by a research grant from Gedeon Richter. There are no conflicts of interest for all authors to declare.

TRIAL REGISTRATION NUMBER

N/A.

The HERA (Hyper-response Risk Assessment) Delphi consensus for the management of hyper-responders in in vitro fertilization

PURPOSE

To provide agreed-upon guidelines on the management of a hyper-responsive patient undergoing ovarian stimulation (OS) METHODS: A literature search was performed regarding the management of hyper-response to OS for assisted reproductive technology. A scientific committee consisting of 4 experts discussed, amended, and selected the final statements. A priori, it was decided that consensus would be reached when ≥66% of the participants agreed, and ≤3 rounds would be used to obtain this consensus. A total of 28/31 experts responded (selected for global coverage), anonymous to each other.

RESULTS

A total of 26/28 statements reached consensus. The most relevant are summarized here. The target number of oocytes to be collected in a stimulation cycle for IVF in an anticipated hyper-responder is 15-19 (89.3% consensus). For a potential hyper-responder, it is preferable to achieve a hyper-response and freeze all than aim for a fresh transfer (71.4% consensus). GnRH agonists should be avoided for pituitary suppression in anticipated hyper-responders performing IVF (96.4% consensus). The preferred starting dose in the first IVF stimulation cycle of an anticipated hyper-responder of average weight is 150 IU/day (82.1% consensus). ICoasting in order to decrease the risk of OHSS should not be used (89.7% consensus). Metformin should be added before/during ovarian stimulation to anticipated hyper-responders only if the patient has PCOS and is insulin resistant (82.1% consensus). In the case of a hyper-response, a dopaminergic agent should be used only if hCG will be used as a trigger (including dual/double trigger) with or without a fresh transfer (67.9% consensus). After using a GnRH agonist trigger due to a perceived risk of OHSS, luteal phase rescue with hCG and an attempt of a fresh transfer is discouraged regardless of the number of oocytes collected (72.4% consensus). The choice of the FET protocol is not influenced by the fact that the patient is a hyper-responder (82.8% consensus). In the cases of freeze all due to OHSS risk, a FET cycle can be performed in the immediate first menstrual cycle (92.9% consensus).

CONCLUSION

These guidelines for the management of hyper-response can be useful for tailoring patient care and for harmonizing future research.

The utility of all-freeze IVF cycles depends on the composition of study populations

BACKGROUND

Because often introduced without proper validation studies, so-called "add-ons" to IVF have adversely affected in vitro fertilization (IVF) outcomes worldwide. All-freeze cycles (embryo banking, EB) with subsequently deferred thaw cycles are such an "add-on" and, because of greatly diverging reported outcomes, have become increasingly controversial. Based on "modeling" with selected patient populations, we in this study investigated whether reported outcome discrepancies may be the consequence of biased patient selection.

RESULTS

In four distinct retrospective case control studies, we modeled in four cohort pairings how cryopreservation with subsequent thaw cycles affects outcomes differently in good-, average- and poor-prognosis patients: (i) 127 fresh vs. 193 frozen donor-recipient cycles to model best-prognosis patients; (ii) 741 autologous fresh non-donor IVF cycles vs. 217 autologous frozen non-donor IVF cycles to model average prognosis patients; (iii) 143 favorably selected autologous non-donor IVF cycles vs. the same 217 frozen autologous cycles non-donor to monitor good- vs. average-prognosis patients; and (iv) 598 average and poor-prognosis autologous non-donor cycles vs. the same 217 frozen autologous non-donor cycles to model poor vs. average prognosis patients. In best-prognosis patients, EB marginally improved IVF outcomes. In unselected patients, EB had no effects. In poor-prognosis patients, EB adversely affected IVF outcomes. Unexpectedly, the study also discovered independent-of-age-associated chromosomal abnormalities, a previously unreported effect of recipient age on miscarriage risk in donor-egg recipients.

CONCLUSIONS

In poor-prognosis patients, EB cycles should be considered contraindicated. In intermediate-prognosis patients EB does not appear to change outcomes, not warranting additional cost and time delays. Therefore, only good-prognosis patients are candidates for EB, though they will experience only marginal benefits that may not be cost-effective.

Assisted Reproductive Technology without Embryo Discarding or Freezing in Women ≥40 Years: A 5-Year Retrospective Study at a Single Center in Italy

The protocols commonly used in assisted reproductive technology (ART) consist of long-term embryo culture up to the blastocyst stage after the insemination of all mature oocytes, the freezing of all the embryos produced, and their subsequent transfer one by one. These practices, along with preimplantation genetic testing, although developed to improve the live birth rate (LBR) and reduce the risk of multiple pregnancies, are drawing attention to the possible increase in obstetric and perinatal risks, and adverse epigenetic consequences in offspring. Furthermore, ethical-legal concerns are growing regarding the increase in cryopreservation and storage of frozen embryos. In an attempt to reduce the risk associated with prolonged embryo culture and avoid embryo storage, we have chosen to inseminate a limited number of oocytes not exceeding the number of embryos to be transferred, after two days or less of culture. We retrospectively analyzed 245 ICSI cycles performed in 184 infertile couples with a female partner aged ≥40 from January 2016 to July 2021. The results showed a fertilization rate of 95.7%, a miscarriage rate of 48.9%, and a LBR of 10% with twin pregnancies of 16.7%. The cumulative LBR in our group of couples was 13%. No embryos were frozen. In conclusion, these results suggest that oocyte selection and embryo transfer at the cleaving stage constitute a practice that has a LBR comparable to that of the more commonly used protocols in older women who have reduced ovarian reserve.

Neonatal Outcomes and Long-Term Follow-Up of Children Born from Frozen Embryo, a Narrative Review of Latest Research Findings

In recent years, the growing use of ART (assisted reproductive techniques) has led to a progressive improvement of protocols; embryo freezing is certainly one of the most important innovations. This technique is selectively offered as a tailored approach to reduce the incidence of multiple pregnancies and, most importantly, to lower the risk of developing ovarian hyperstimulation syndrome when used in conjunction with an ovulation-triggering GnRH antagonist. The increase in transfer cycles with frozen embryos made it possible to study the effects of the technique in children thus conceived. Particularly noteworthy is the increase in macrosomal and LGA (large for gestational age) newborns, in addition to a decrease in SGA (small for gestational age) and LBW (low birth weight) newborns. The authors aimed to outline a broad-ranging narrative review by summarizing and elaborating on the most important evidence regarding the neonatal outcome of children born from frozen embryos and provide information on the medium and long-term follow- up of these children. However, given the relatively recent large-scale implementation of such techniques, further studies are needed to provide more conclusive evidence on outcomes and implications.

The impact of embryo vitrification on placental histopathology features and perinatal outcome in singleton live births

STUDY QUESTION

Does embryo vitrification affect placental histopathology pattern and perinatal outcome in singleton live births?

SUMMARY ANSWER

Embryo vitrification has a significant effect on the placental histopathology pattern and is associated with a higher prevalence of dysfunctional labor.

WHAT IS KNOWN ALREADY

Obstetrical and perinatal outcomes differ between live births resulting from fresh and frozen embryo transfers. The effect of embryo vitrification on the placental histopathology features associated with the development of perinatal complications remains unclear.

STUDY DESIGN, SIZE, DURATION

Retrospective cohort study evaluating data of all live births from one academic tertiary hospital resulting from IVF treatment with autologous oocytes during the period from 2009 to 2017.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All patients had placentas sent for pathological evaluation irrelevant of maternal or fetal complications status. Placental, obstetric and perinatal outcomes of pregnancies resulting from hormone replacement vitrified embryo transfers were compared with those after fresh embryo transfers. A multivariate analysis was conducted to adjust the results for determinants potentially associated with the development of placental histopathology abnormalities.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 1014 singleton live births were included in the final analysis and were allocated to the group of pregnancies resulting from fresh (n = 660) and hormone replacement frozen (n = 354) embryo transfers. After the adjustment for confounding factors the frozen embryo transfers were found to be significantly associated with chorioamnionitis with maternal (odds ratio (OR) 2.0; 95% CI 1.2-3.3) and fetal response (OR 2.6; 95% CI 1.2-5.7), fetal vascular malperfusion (OR 3.9; 95% CI 1.4-9.2), furcate cord insertion (OR 2.3 95% CI 1.2-5.3), villitis of unknown etiology (OR 2.1; 95% CI 1.1-4.2), intervillous thrombi (OR 2.1; 95% CI 1.3-3.7), subchorionic thrombi (OR 3.4; 95% CI 1.6-7.0), as well as with failure of labor progress (OR 2.5; 95% CI 1.5-4.2).

LIMITATIONS, REASONS FOR CAUTION

Since the live births resulted from frozen-thawed embryos included treatment cycles with previously failed embryo transfers, the factors over embryo vitrification may affect implantation and placental histopathology.

WIDER IMPLICATIONS OF THE FINDINGS

The study results contribute to the understanding of the perinatal future of fresh and vitrified embryos. Our findings may have an implication for the clinical decision to perform fresh or frozen-thawed embryo transfer.

STUDY FUNDING/COMPETING INTEREST(S)

Authors have not received any funding to support this study. There are no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Revisiting selected ethical aspects of current clinical in vitro fertilization (IVF) practice

Ethical considerations are central to all medicine though, likely, nowhere more essential than in the practice of reproductive endocrinology and infertility. Through in vitro fertilization (IVF), this is the only field in medicine involved in creating human life. IVF has, indeed, so far led to close to 10 million births worldwide. Yet, relating to substantial changes in clinical practice of IVF, the medical literature has remained surprisingly quiet over the last two decades. Major changes especially since 2010, however, call for an updated commentary. Three key changes deserve special notice: Starting out as a strictly medical service, IVF in recent years, in efforts to expand female reproductive lifespans in a process given the term “planned” oocyte cryopreservation, increasingly became more socially motivated. The IVF field also increasingly underwent industrialization and commoditization by outside financial interests. Finally, at least partially driven by industrialization and commoditization, so-called add-ons, the term describing mostly unvalidated tests and procedures added to IVF since 2010, have been held responsible for worldwide declines in fresh, non-donor live birthrates after IVF, to levels not seen since the mid-1990s. We here, therefore, do not offer a review of bioethical considerations regarding IVF as a fertility treatment, but attempt to point out ethical issues that arose because of major recent changes in clinical IVF practice.

Extended culture of cleavage-stage embryos in vitrified-thawed cycles may be an alternative to frozen and thawed blastocysts during in vitro fertilization

AIM

We compared the clinical outcomes of vitrified-thawed cycles during in vitro fertilization (IVF) for frozen and thawed blastocysts compared to cleavage-stage embryos that were frozen, thawed and extended culture to the blastocyst stage.

MATERIAL AND METHODS

Between January 2014 and December 2016, 908 frozen-thawed cycles were included in the study. After removing cycles that met exclusion criteria, clinical outcomes for 355 cleavage-stage embryos with extended blastocyst culture (Group I) were compared with 279 frozen and thawed blastocysts (Group II).

RESULTS

Cryo-survival rate of the two groups were similar (96.7% versus 95.0%). Implantation rates (28.9% versus 22.4%, p = .04) and clinical pregnancy rates (37.2% versus 27.9%, p = .03) were higher in Group I. Pregnancy, live birth and abortus rates were similar in both groups. Although overall abortus rates were similar in both groups, abortus rates before 12 weeks of gestation were higher in Group I, and chemical abortus rates were higher in Group II (p = .03, p = .04). Weeks of gestation at birth and birth weight were similar in both groups.

CONCLUSIONS

The use of extended blastocyst culture of cleavage-stage embryos was not inferior to frozen and thawed blastocysts. Freezing at the cleavage-stage can provide similar cryo-survival rates than blastocyst vitrification. Vitrifying surplus or all embryos for storage at the cleavage-stage allows higher implantation and clinical pregnancy rates. But after abortus, live birth rates were similar in both groups.

The effects of post-frozen-thawed embryo transfer pregnancy on early fetal development

AIM

Frozen-thawed embryo transfer (FET) has gained popularity as an assistive reproductive technology despite its increased risk of large-for-gestational-age offspring. This study aimed to analyze the effect of FET on fetal development, particularly the growth rate and estimated fetal weight (EFW) throughout pregnancy.

METHODS

This was a single-center, retrospective study that examined 97 patients with FET conception and 477 patients with natural conception (NC) who underwent labor and delivery at our clinic between December 2015 and June 2019. Crown-rump length (CRL) in the first trimester and EFW measurements in the second and third trimesters were obtained from transabdominal ultrasound records. Birthweight was adjusted for sex, parity, and gestational age. Regression coefficients of CRL, EFW, and birthweight were compared between the FET and NC groups to examine the growth rate. Multiple regression analysis was performed to determine the relationship between birth size and baseline characteristics.

RESULTS

The growth rate was higher in the first trimester in the FET group than in the NC group (difference: 0.19 mm/day, p = 0.018). CRL, EFW, and adjusted birthweight were higher in the FET group than in the NC group throughout pregnancy. The factors associated with the development of larger offspring through FET than through NC were advanced maternal age, primiparity, cesarean section delivery, and high birthweight.

CONCLUSIONS

Throughout pregnancy, FET resulted in a larger offspring than in NC, with accelerated growth observed only during the first trimester. Thus, FET highly affects early fetal development.

Maternal and neonatal outcomes following in vitro fertilization: A cohort study in Romania

Although in recent years the number of pregnancies obtained through in vitro fertilization (IVF) has increased significantly, a higher incidence of complications has been identified in this group. The widespread development and use of IVF has led to an increasing rate of multiple pregnancies and thus their associated complications. However, whether these complications occur due to assisted reproduction or infertility problems remains to be elucidated. In the present study, a comparison was made of IVF pregnancies with spontaneous conception, and the risk of obstetric and neonatal complications was assessed. An ambispective observational cohort study was carried out between January 2017 and October 2021 at Elias University Emergency Hospital, Romania. The exposed cohort included 132 IVF pregnancies and the control cohort included 157 spontaneous pregnancies. The IVF group included 110 pregnancies with fresh embryo-transfer and 22 pregnancies with cryopreserved embryo-transfer. Obstetric, perinatal and neonatal complications were analysed by multivariable logistic analysis. The results showed that, IVF pregnancies had a higher risk of pregnancy-induced hypertension (OR=6.42, 95% CI=1.72-23.92) and placental abnormalities (OR=5.49, 95% CI=1.07-28.17). Neonates obtained through IVF had a higher risk of prematurity (OR=6.52, 95% CI=2.99-14.20), low birth weight (LBW) (OR=17.18, 95% CI=7.06-41.87), small for gestational age (OR=4.10, 95% CI=1.95-8.59) and were more frequently hospitalized in the Neonatal Intensive Care Unit (NICU) (OR=11.91, 95% CI=5.72-24.81). Nulliparous women were associated with an increased risk of NICU admission (OR=0.46, 95% CI=0.25-0.88) and risk of LBW (OR=0.37, 95% CI=0.19-0.75). Maternal age ≥35 years had no influence as a confounding variable. In conclusion, this cohort study showed that IVF pregnancies have a higher risk of obstetric and neonatal complications than pregnancies obtained by spontaneous conception.

Obstetric and Perinatal Complications Associated with Assisted Reproductive Techniques - Review

Recently, the use of assisted reproductive techniques (ART) has witnessed a significant increase worldwide. Although most of these pregnancies have a good prognosis, studies show that ART is associated with a risk of obstetric and perinatal complications, compared to pregnancies conceived spontaneously. It is considered that the risk is directly proportional to the number of transferred embryos, thus multiple pregnancies are an independent risk factor that supports the large-scale implementation of single embryo transfer protocols. Simultaneously, studies report obstetric and perinatal complications in singleton pregnancies obtained after ART and it is not possible to establish whether parental or procedural factors are the causal determinants. The purpose of this article is to summarize the risk of maternal-fetal complications associated with ART.

Natural cycle versus hormone replacement cycle for transferring vitrified-warmed embryos in eumenorrhoeic women. A retrospective cohort study

OBJECTIVE

To compare pregnancy, miscarriage and live birth rates and cycle monitoring parameters between Natural Cycle (NC-FET) and Hormone replacement cycle (HRC-FET) in eumenorrhoeic women undergoing vitrified-warmed autologous embryo transfer.

STUDY DESIGN

Single-centre retrospective cohort study analyzed 173 NC-FET and 507 HRC-FET cycles with transfer of day2/3/5/6 embryos. Natural cycle monitoring occurred with serial ultrasound with the first day of the scan determined by the shortest cycle frequency. Serum progesterone was ordered when ultrasound was ambiguous in ascertaining ovulation. For HRC-FET oral estradiol valerate was used in fixed or escalating doses with maximum daily dose of 12 mg. Transdermal estradiol gel was added when desired endometrial thickness was not achieved. Vaginal progesterone was introduced with Endometrial thickness(ET)> = 7 mm. Embryos were transferred after stage-appropriate progesterone exposure. Luteal support was given with vaginal progesterone in NC-FET and vaginal and oral progesterone in HRC-FET. Primary outcome was live-birth-rate. Secondary outcomes were ET, length-of-estrogenic-phase, numbers-of-ultrasounds&hormone-monitoring, pregnancy&miscarriage rate. The odds ratio for live-birth was adjusted for age, embryo number, previous-live-births, previous-losses, past-negative-ET-cycles, IVF-indication and embryo-developmental-stage. Quantitative variables were compared using unpaired-t-test and qualitative variables with chi-square test. Two tailed p-value < 0.05 was considered significant. Binary logistic regression was used to calculate adjusted odds for live-births.

RESULTS

The two cohorts were comparable in age, infertility-duration, previous-live-births, previous-losses, past-negative-ET-cycles, IVF-indication and embryo-developmental-stage. Length-of-estrogenic-phase was significantly shorter for NC-FET than HRC-FET 14.32 ± 2.83vs.18.18 ± 4.48; p = 0.0001) as was mean ultrasound-monitoring-scans (2.73 ± 0.95vs. 3.3 ± 1.04; p = 0.0001). Mean-endometrial-thickness (8.75 ± 1.83vs. 8.5 ± 1.25; p = 0.25) and mean-hormonal-tests (1.75 ± 1.28 vs. 1.88 ± 0.69; p = 0.09) did not differ significantly between NC-FET vs HRC-FET. Significantly higher live births took place in NC-FET vs. HRC-FET (87/173 = 50.3%vs.204/507 = 40.2%;p = 0.026). No significant difference was found in pregnancy rate (66.5% vs. 58%; p = 0.058) or in the pregnancy loss rate (24.3%vs30.6%; p = 0.23). The odds ratio for live-births adjusted for relevant variables was 1.48 (1.03-2.13) in NC-FET compared to HRC-FET.

CONCLUSIONS

NC-FET is a superior method of endometrial preparation compared to HRC-FET in eumenorrhoeic women since it has a shorter estrogenic phase, reduces patient visits to the hospital and improves live birth rates. Future adequately powered studies should look at antenatal and perinatal outcomes, patient satisfaction rates and cost-effectiveness in the two endometrial preparation regimes.

When Should We Freeze Embryos? Current Data for Fresh and Frozen Embryo Replacement IVF Cycles

Recent years have seen a dramatic rise in the number of frozen-thawed embryo replacement (FER) cycles. Along with the advances in embryo cryopreservation techniques, the optimization of endometrial receptivity has resulted in outcomes for FER that are similar to fresh embryo transfer. However, the question of whether the Freeze all strategy is for all is nowadays a hot topic. This review addresses this issue and describes current evidence based on randomized controlled trials and observational studies. To date, it is reasonable to perform FER in cases with a clear indication for the benefits of such strategy including impending ovarian hyperstimulation syndrome (OHSS) or preimplantation genetic testing for aneuploidy (PGT-A); however, this strategy does not fit for all. This review analyses the pros and cons of the freeze all strategy highlighting the need to follow a personalized plan in embryo transfer, avoiding a freeze all methodology for all patients in an unselected manner.

The long-term effect of prenatal progesterone treatment on child development, behaviour and health: a systematic review

BACKGROUND

Progesterone is widely used in prenatal care. However, long-term effects of prenatal progesterone treatment on child development are unclear.

OBJECTIVES

To evaluate long-term outcomes in children after prenatal progesterone treatment.

SEARCH STRATEGY

MEDLINE, Embase and Cochrane Central Register of Controlled Trials from inception to 24 May 2020.

SELECTION CRITERIA

Randomised controlled trials (RCTs) reporting outcomes in children born to women who received progesterone treatment (compared with placebo or another intervention) during any trimester in pregnancy.

DATA COLLECTION AND ANALYSIS

Two authors independently selected and extracted data. We used the Cochrane Risk of Bias tool for randomised trials and Quality In Prognosis Studies.

MAIN RESULTS

Of 388 papers, we included seven articles based on five RCTs, comprising 4222 measurements of children aged 6 months to 8 years. All studies compared progesterone to placebo in second and/or third trimester for the prevention of preterm birth. Meta-analysis (two studies, n = 890 children) showed no difference in neurodevelopment as assessed by the Bayley-III Cognitive Composite score at 2 years between children exposed to progesterone versus placebo (Standardised Mean Difference -0.04, 95% Confidence Interval -0.26 to 0.19), I2  = 22%. Heterogeneity prohibited additional meta-analyses. Other long-term outcomes showed no differences.

CONCLUSIONS

Our systematic review comprising a multitude of developmental measurements with a broad age range did not find evidence of benefit or harm in offspring prenatally exposed to progesterone treatment for the prevention of preterm birth. We identified an urgent need for follow-up studies of prenatal progesterone administration in early pregnancy and effects in offspring beyond early childhood.

TWEETABLE ABSTRACT

Progesterone to prevent preterm birth: no effect on child development. Outcomes after first trimester progesterone are unclear.

Microsomic and macrosomic body structure in children and adolescents affected by syndromes or diseases associated with neurodysfunction

In Poland the issue of microsomic body structure (micro-SBS) and macrosomic body structure (macro-SBS) has so far been overlooked. Up until now only a small amount of data have been published, most often as an overview of the problem. The current study was designed to investigate the co-occurrence of microsomic/macrosomic body structure (micro/macro-SBS) and congenital nervous system disorders or neurological syndromes with symptoms visible from infancy, based on essential data acquired during admission procedures at a neurological rehabilitation ward for children and adolescents. The study applied a retrospective analysis of data collected during hospitalization of 327 children and adolescents, aged 4-18 years who had been affected since infancy by congenital disorders of the nervous system and/or neurological syndromes associated with a minimum of one neurodysfunction. To identify subjects with microsomic or macrosomic body structure in the group of children and adolescents, the adopted criteria took into account z-score values for body height (z-score Ht), body weight (z-score Wt), head circumference (z-score HC), BMI (z-score BMI) and head circumference index (z-score HCI). The rates of micro/macro-SBS in the study group amounted to 7.3% and 0.6%, respectively. The findings show a more frequent co-occurrence of, as well as statistically significant correlations between, micro/macro-SBS and type of spasticity (cerebral palsy) (p = 0.024) as well as hydrocephalus not treated surgically (p < 0.001). Macro-SBS was found to more frequently co-occur with hemiplegia and hydrocephalus not treated surgically.

Assisted reproductive technology, justice and autonomy in an era of COVID-19

Fertility services were significantly curtailed or suspended as an initial response to the coronavirus (COVID-19) pandemic earlier this year, following guidance from European Society for Human Reproduction and Embryology (ESHRE) and the American Society for Reproductive Medicine (ASRM) as well as a General Direction (GD0014) issued by the Human Fertilisation and Embryo Authority (HFEA). It is difficult to argue with triage of medical care and resources in the face of anticipated overwhelming demand, but this situation resulted in considerable distress, as shown by a change.org petition opposing ASRM recommendations, which has gathered over 21,000 signatures to date. Although halting assisted reproductive technology (ART) as the pandemic unfolded was ethical because public health goals superseded individual patient autonomy, the fertility sector now faces a greater challenge balancing ethical considerations in an era characterized by the ongoing threat of COVID-19. This article discusses justice and autonomy in the context of ART, potential conflicts and resolutions.

Randomized study of G-TL and global media for blastocyst culture in the EmbryoScope: morphokinetics, pregnancy, and live births after single-embryo transfer

OBJECTIVE

To evaluate the efficacy of two different in vitro fertilization culture media for blastocyst development, pregnancy, and live birth rate. Global (GB) medium (used without refreshment) and G-TL medium (designed specifically for culture in time-lapse incubators) were compared.

DESIGN

Prospective randomized study of sibling embryo culture in two culture media.

SETTING

In vitro fertilization clinic.

PATIENT(S)

Women undergoing fresh or frozen cycles using autologous or donor oocytes.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The primary endpoints were implantation, pregnancy, and live birth rate (LBR) after single blastocyst transfer. Secondary endpoints included embryo morphokinetics, development of good-quality blastocysts, and euploidy rate.

RESULT(S)

Kinetic data from 10,768 sibling pronucleate embryos cultured in the EmbryoScope were compared. GB embryos initiated compaction earlier and formed morula sooner than their G-TL counterparts. The mean timing for start of blastulation did not differ. The interval between start of blastulation and time of blastocyst formation was observed to be <12 hours for proportionately more GB compared with G-TL-cultured embryos. Despite a higher rate of observed dysmorphisms in GB embryos, the euploidy rate among biopsied blastocysts did not differ between media. A total of 820 single-embryo transfer cycles were performed. Implantation rates were similar between media, independent of whether the embryo transferred was fresh (GB 58.7% vs. G-TL 61.7%) or frozen (GB 64.1% vs. G-TL 60.5%). Live birth rates were also not different. With GB medium, the LBR for fresh and frozen transfers was 54.2% and 53.1%, respectively, as compared with 51.1% and 50%, respectively, with G-TL.

CONCLUSION(S)

Uninterrupted culture in a time-lapse incubator without medium refreshment was well supported by both media tested. Differences in morphokinetics did not necessarily dictate the superiority of one media over the other. Both pregnancy and LBR were not significantly influenced by choice of culture medium. The euploidy rate was also independent of culture medium.

Number of embryos transferred and diagnosis of preeclampsia

BACKGROUND

Multiple births and first pregnancy are associated with higher preeclampsia risk. It is unknown if the transfer of multiple embryos or first embryo transfer with assisted reproductive technology (ART) is also associated with greater preeclampsia risk.

METHODS

We performed a retrospective cohort study of IVF clinics and hospitals in Massachusetts. We used linked ART surveillance, birth certificate, and maternal hospitalization discharge data for 21,188 births, considering resident singleton (12,810) and twin (8378) live-births from autologous or donor eggs from 2005 to 2012. We used log binomial and Poisson regression to calculate adjusted relative risks (aRRs) and 95% confidence intervals (CI) for the association between preeclampsia and predictors of preeclampsia. Outcomes were stratified by singleton and twin birth, donor versus autologous cycles, and use of fresh versus cryopreserved embryos.

RESULTS

Considering all singleton births, the transfer of multiple embryos increased the risk of preeclampsia [aRR = 1.10 (95% CI: 1.01-1.19)]. Relative risks were greatest for fresh non-donor cycles [aRR = 1.14 (95% CI: 1.03-1.26)]. Vanishing twin and number of prior ART cycles was not associated with preeclampsia among singleton births [aRR = 1.18 (95% CI: 0.91-1.53)], and aRR = 1.01 (95% CI: 0.96-1.05)], respectively. Considering all twin births, the transfer of > 2 embryos increased the risk of preeclampsia [aRR = 1.09 (95% CI: 1.001-1.19)]. Vanishing triplet and number of prior ART cycles were not associated with preeclampsia among twin births [aRR = 0.93 (95% CI: 0.69-1264), and aRR = 0.98 (CI: 0.95-1.02)], respectively.

CONCLUSIONS

Among ART births, the transfer of more than 1 embryo for singleton gestations and more than 2 embryos for twin gestations increased the risk for preeclampsia diagnosis.