Good practice recommendations on add-ons in reproductive medicine†

STUDY QUESTION

Which add-ons are safe and effective to be used in ART treatment?

SUMMARY ANSWER

Forty-two recommendations were formulated on the use of add-ons in the diagnosis of fertility problems, the IVF laboratory and clinical management of IVF treatment.

WHAT IS KNOWN ALREADY

The innovative nature of ART combined with the extremely high motivation of the patients has opened the door to the wide application of what has become known as 'add-ons' in reproductive medicine. These supplementary options are available to patients in addition to standard fertility procedures, typically incurring an additional cost. A diverse array of supplementary options is made available, encompassing tests, drugs, equipment, complementary or alternative therapies, laboratory procedures, and surgical interventions. These options share the common aim of stating to enhance pregnancy or live birth rates, mitigate the risk of miscarriage, or expedite the time to achieving pregnancy.

STUDY DESIGN, SIZE, DURATION

ESHRE aimed to develop clinically relevant and evidence-based recommendations focusing on the safety and efficacy of add-ons currently used in fertility procedures in order to improve the quality of care for patients with infertility.

PARTICIPANTS/MATERIALS, SETTING, METHODS

ESHRE appointed a European multidisciplinary working group consisting of practising clinicians, embryologists, and researchers who have demonstrated leadership and expertise in the care and research of infertility. Patient representatives were included in the working group. To ensure that the guidelines are evidence-based, the literature identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, recommendations were based on the professional experience and consensus of the working group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 46 independent international reviewers. A total of 272 comments were received and incorporated where relevant.

MAIN RESULTS AND THE ROLE OF CHANCE

The multidisciplinary working group formulated 42 recommendations in three sections; diagnosis and diagnostic tests, laboratory tests and interventions, and clinical management.

LIMITATIONS, REASONS FOR CAUTION

Of the 42 recommendations, none could be based on high-quality evidence and only four could be based on moderate-quality evidence, implicating that 95% of the recommendations are supported only by low-quality randomized controlled trials, observational data, professional experience, or consensus of the development group.

WIDER IMPLICATIONS OF THE FINDINGS

These guidelines offer valuable direction for healthcare professionals who are responsible for the care of patients undergoing ART treatment for infertility. Their purpose is to promote safe and effective ART treatment, enabling patients to make informed decisions based on realistic expectations. The guidelines aim to ensure that patients are fully informed about the various treatment options available to them and the likelihood of any additional treatment or test to improve the chance of achieving a live birth.

STUDY FUNDING/COMPETING INTEREST(S)

All costs relating to the development process were covered from ESHRE funds. There was no external funding of the development process or manuscript production. K.L. reports speakers fees from Merck and was part of a research study by Vitrolife (unpaid). T.E. reports consulting fees from Gynemed, speakers fees from Gynemed and is part of the scientific advisory board of Hamilton Thorne. N.P.P. reports grants from Merck Serono, Ferring Pharmaceutical, Theramex, Gedeon Richter, Organon, Roche, IBSA and Besins Healthcare, speakers fees from Merck Serono, Ferring Pharmaceutical, Theramex, Gedeon Richter, Organon, Roche, IBSA and Besins Healthcare. S.R.H. declares being managing director of Fertility Europe, a not-for-profit organization receiving financial support from ESHRE. I.S. is a scientific advisor for and has stock options from Alife Health, is co-founder of IVFvision LTD (unpaid) and received speakers' fee from the 2023 ART Young Leader Prestige workshop in China. A.P. reports grants from Gedeon Richter, Ferring Pharmaceuticals and Merck A/S, consulting fees from Preglem, Novo Nordisk, Ferring Pharmaceuticals, Gedeon Richter, Cryos and Merck A/S, speakers fees from Gedeon Richter, Ferring Pharmaceuticals, Merck A/S, Theramex and Organon, travel fees from Gedeon Richter. The other authors disclosed no conflicts of interest.

DISCLAIMER

This Good Practice Recommendations (GPRs) document represents the views of ESHRE, which are the result of consensus between the relevant ESHRE stakeholders and are based on the scientific evidence available at the time of preparation.ESHRE GPRs should be used for information and educational purposes. They should not be interpreted as setting a standard of care or bedeemedinclusive of all proper methods of care, or be exclusive of other methods of care reasonably directed to obtaining the same results.Theydo not replace the need for application of clinical judgement to each individual presentation, or variations based on locality and facility type.Furthermore, ESHRE GPRs do not constitute or imply the endorsement, or favouring, of any of the included technologies by ESHRE.

NKG2A educates uterine NK cells to optimise pregnancy outcomes in humans and mice

The conserved CD94/NKG2A receptor binds HLA-E in humans and Qa-1 in mice. Besides inhibiting natural killer (NK) cell activation, NKG2A drives NK-cell education, a process influenced by HLA-B alleles that promotes NK cell function. In human populations some individuals are genetically programmed to favour NKG2A education and have more robust NK cell function. NKG2A is expressed by nearly all human and roughly half mouse uterine NK cells (uNK), but the importance of NK-cell education in physiology is unknown.

Here we show that NKG2A was required for uNK cell-education in dams. Genetic ablation of NKG2A caused sub-optimal vascular responses in pregnancy, increased rate of smaller fetuses, which grew asymmetrically with abnormal brain development, and changes in placental gene expression consistent with stress. These are features of the human syndrome pre-eclampsia. In a genome-wide association study of 7,219 cases and 155,660 control pregnancies, we found that the maternal HLA-B allele that does not favour NKG2A education, was associated with a 7% greater relative risk of pre-eclampsia (P=0.005, OR= 1.07).

These results establish the relevance of NK cell education in physiology and show that the maternal HLA-B –> HLA-E –> NKG2A pathway contributes to healthy pregnancy and may influence offspring health.

Collagen type IV at the fetal-maternal interface

Introduction

Extracellular matrix proteins play a crucial role in influencing the invasion of trophoblast cells. However the role of collagens and collagen type IV (col-IV) in particular at the implantation site is not clear.

Methods

Immunohistochemistry was used to determine the distribution of collagen types I, III, IV and VI in endometrium and decidua during the menstrual cycle and the first trimester of pregnancy. Expression of col-IV alpha chains during the reproductive cycle was determined by qPCR and protein localisation by immunohistochemistry. The structure of col-IV in placenta was examined using transmission electron microscopy. Finally, the expression of col-IV alpha chain NC1 domains and collagen receptors was localised by immunohistochemistry.

Results

Col-IV alpha chains were selectively up-regulated during the menstrual cycle and decidualisation. Primary extravillous trophoblast cells express collagen receptors and secrete col-IV in vitro and in vivo, resulting in the increased levels found in decidua basalis compared to decidua parietalis. A novel expression pattern of col-IV in the mesenchyme of placental villi, as a three-dimensional network, was found. NC1 domains of col-IV alpha chains are known to regulate tumour cell migration and the selective expression of these domains in decidua basalis compared to decidua parietalis was determined.

Discussion

Col-IV is expressed as novel forms in the placenta. These findings suggest that col-IV not only represents a structural protein providing tissue integrity but also influences the invasive behaviour of trophoblast cells at the implantation site.

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Our data suggest that progesterone might regulate collagen type IV.

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Primary extravillous trophoblast cells secrete collagen type IV.

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A novel three-dimensional network of collagen type IV in placenta is presented.

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Trophoblast cells express integrin alpha 10, integrin alpha 11 and collagen receptors DDR-1 and DDR-2.

IFPA Meeting 2011 workshop report III: Placental immunology; epigenetic and microRNA-dependent gene regulation; comparative placentation; trophoblast differentiation; stem cells

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialised topics. At IFPA meeting 2011 there were twelve themed workshops, five of which are summarized in this report. These workshops related to various aspects of placental biology: 1) immunology; 2) epigenetics; 3) comparative placentation; 4) trophoblast differentiation; 5) stem cells.

Genome-wide expression profile of first trimester villous and extravillous human trophoblast cells

We have examined the transcriptional changes associated with differentiation from villous to extravillous trophoblast using a whole genome microarray. Villous trophoblast (VT) is in contact with maternal blood and mediates nutrient exchange whereas extravillous trophoblast (EVT) invades the decidua and remodels uterine arteries. Using highly purified first trimester trophoblast we identified over 3000 transcripts that are differentially expressed. Many of these transcripts represent novel functions and pathways that show co-ordinated up-regulation in VT or EVT. In addition we identify new players in established functions such as migration, immune modulation and cytokine or angiogenic factor secretion by EVT. The transition from VT to EVT is also characterised by alterations in transcription factors such as STAT4 and IRF9, which may co-ordinate these changes. Transcripts encoding several members of the immunoglobulin-superfamily, which are normally expressed on leukocytes, were highly transcribed in EVT but not expressed as protein, indicating specific control of translation in EVT. Interactions of trophoblast with decidual leukocytes are involved in regulating EVT invasion. We show that decidual T-cells, macrophages and NK cells express the inhibitory collagen receptor LAIR-1 and that EVT secrete LAIR-2, which can block this interaction. This represents a new mechanism by which EVT can modulate leukocyte function in the decidua. Since LAIR-2 is detectable in the urine of pregnant, but not non-pregnant women, trophoblast-derived LAIR-2 may also have systemic effects during pregnancy.

Association of maternal killer-cell immunoglobulin-like receptors and parental HLA-C genotypes with recurrent miscarriage

BACKGROUND

The natural killer (NK) cells at the site of placentation express killer-cell immunoglobulin-like receptors (KIR) that can bind to human leukocyte antigen (HLA)-C molecules on trophoblast cells. Both these gene systems are polymorphic and an association of particular maternal KIR/fetal HLA-C genotypes has been shown in pre-eclampsia. Pre-eclampsia and recurrent miscarriage (RM) share the pathogenesis of defective placentation and therefore we have now genotyped couples with RM.

METHODS AND RESULTS

DNA was obtained from the male (n = 67) and female (n = 95) partners of couples with three or more spontaneous miscarriages and genotyped for HLA-C groups and 11 KIR genes using the PCR-sequence-specific primer method (SSP). The frequency of the HLA-C2 group was increased in both parents (reaching significance only in the male partners, P = 0.018) compared with a parous control population. The KIR gene frequencies of the male partners were similar to controls, but the women had a high frequency of KIR AA haplotypes that lack activating KIR. In particular, the activating KIR for HLA-C2 groups (KIR2DS1) was significantly lower in these women (P = 0.00035, odds ratio 2.63, confidence interval 1.54-4.49).

CONCLUSIONS

This is the first report to identify a genetic male factor that confers risk in RM. These findings support the idea that successful placentation depends on the correct balance of NK cell inhibition and activation in response to trophoblast.

How Does the Maternal Immune System Contribute to the Development of Pre-eclampsia?

An immunological aura has hovered over the study of pre-eclampsia for many years but there has still been little progress in explaining the various 'immune' phenomena associated with this elusive disease. When considering the primary defect of placentation that leads to pre-eclampsia the focus should be on the intermingling of the invasive placental trophoblast cells with maternal leukocytes in the uterine wall. The MHC status of trophoblast cells is a crucial factor to be considered, as these molecules can act as ligands for uterine immune cells, including T cells, NK cells and myelomonocytic cells. Extravillous trophoblast cells express an unusual combination of HLA-C, HLA-G and HLA-E molecules and only one of these HLA molecules, HLA-C, shows any appreciable polymorphism. In humans, uNK cells express an array of receptors, some of which are known to bind to the HLA class I molecules expressed by extravillous trophoblast cells. HLA-C is the dominant ligand for killer immunoglobulin-like receptors (KIR) expressed by uterine NK cells that may deliver an inhibitory or activating signal. KIR haplotypes comprise two groups, A and B; these differ principally by having additional activating receptors in the B haplotype. In any pregnancy, the maternal KIR genotype could be AA (no activating KIR) or AB/BB (presence of between one and five activating KIRs). The HLA-C ligands for KIR on trophoblast cells may belong to two groups, C1 and C2 that are defined by a dimorphism at position 80 of the alpha1 domain. This maternal-fetal immunological interaction, occurring at the site of placentation, therefore involves two polymorphic gene systems, maternal KIRs and fetal HLA-C molecules. Uterine NK-cell function is thus likely to vary in each pregnancy. In pre-eclamptic pregnancies we have found that some KIR/HLA-C combinations appear unfavourable to trophoblast-cell invasion due to the overall signals that the NK cell receives. The academic excitement of this work is the realisation that this is a novel form of allorecognition based on NK cells that operates entirely differently from self/non-self discrimination used by T cells.

Consistent patterns of expression of HLA class I free heavy chains in healthy individuals and raised expression in spondyloarthropathy patients point to physiological and pathological roles

OBJECTIVES

Major histocompatibility complex class I (MHC-I) proteins exist at the cell surface in antigen presenting forms and as beta2m-independent free heavy chains (FHCs). FHCs have been implicated in spondyloarthritis, but little is known about their expression in healthy individuals. We studied FHC expression on various human cell types, comparing spondyloarthropathy patients with healthy and rheumatoid arthritis (RA) patient controls.

METHODS

MHC-I expression was analysed by flow cytometry. FHC levels were normalized for overall MHC-I to generate a relative expression level. Relative FHC levels were analysed for peripheral blood and trophoblast samples from healthy volunteers, RA and spondyloarthropathy patients. Macrophages and dendritic cells were cultured in vitro to analyse changes following activation. Peripheral blood leucocytes from patients with ankylosing spondylitis (AS) and RA were treated with inflammatory stimuli and subsequent alterations in their relative FHC levels were analysed.

RESULTS

We found consistent patterns of differential relative FHC expression across lymphocyte subpopulations and particularly high expression on extravillous trophoblast. FHCs were present at higher levels in a reactive arthritis (ReA) population than in healthy controls and RA patients; differences not merely due to the presence of Human Leucocyte Antigen (HLA) B27. Treatment of leucocytes from arthritic patients with bacterial lipopolysaccharide resulted in significant up-regulation of FHC compared with an HLA B27+ control population.

CONCLUSIONS

Our findings define normal levels and tissue expression of FHCs, and support the hypothesis that disregulation of heavy chain expression may play a pathogenic role in spondyloarthropathy.

Human endogenous retrovirus-W envelope (syncytin) is expressed in both villous and extravillous trophoblast populations

The placenta is unique amongst normal tissues in transcribing numerous different human endogenous retroviruses at high levels. In this study, RT-PCR and immunohistochemistry were used to investigate the expression of syncytin in human trophoblast. Syncytin transcripts were found in first-trimester trophoblast cells with both villous and extravillous phenotypes and also in the JAR and JEG-3 choriocarcinoma cell lines. Syncytin protein was detected in villous trophoblast and in all extravillous trophoblast subpopulations of first- and second-trimester placental tissues. It was also present in ectopic trophoblast from tubal implantations. This study confirms that syncytin is expressed widely by a variety of normal human trophoblast populations, as well as choriocarcinoma cell lines.

Implantation, Embryo–Maternal Interactions, Immunology and Modulation of the Uterine Environment – A Workshop Report

The Workshop discussed five topics which were considered to be topical. 1) A comparison was made between rodents and primates regarding how uNK cells are distributed at the implantation site in these species. 2) The possibility that the functions of uNK cells may be different in mice and humans are discussed. 3) Trophoblast MHC expression in the Rhesus monkey (haemochorial) and the sheep (epitheliochorial) was compared in order the gauge the importance of these molecules in these two fundamentally different types of placentation. 4) New data were presented on the intriguing molecule, HLA-G, whose function is still unclear. 5) A discussion was initiated to debate the role of the innate and the adaptive immune systems in human implantation.

Expression and functions of human endogenous retroviruses in the placenta: an update

The placenta is unique amongst normal tissues in transcribing many different human endogenous retrovirus (HERV) families at high levels and this has led to the suggestion that HERVs may fulfil important functions in reproduction. This review discusses our current knowledge of the placental expression of HERVs, in particular the envelope proteins of ERV3 and HERV-W which may have critical roles in placental function.

The Immunological Paradox of Pregnancy: A Reappraisal

The survival of the allogeneic conceptus has long been an immunological paradox. Medawar was the first to propose an evasive mechanism based on the concept of self/non-self recognition described in classical transplantation immunology. Since then, several newer models of self/non-self recognition have been proposed, such as the PAMP/PRR system, the Missing Self and the Danger Hypothesis. The present paper considers the fetal-maternal relationship in the context of all these models. The conclusion reached is that none of them is really appropriate because the interface between trophoblast cells of the fetal placenta and the leukocytes of the maternal decidua is unique. Pregnancy is not simply a case of acceptance or rejection like a transplant. The immunological mechanism must provide a balanced environment whereby the conceptus is nurtured by the mother and yet prevented from excessive invasion. Future identification of trophoblast ligands and their respective receptors on uterine Natural Killer cells and other leukocytes is likely to offer the best insight as to how this symbiotic state is achieved.

Human uterine leukocytes and pregnancy

In human pregnancy, the embryo implants into the specialized mucosal wall of the uterus (decidua) and the placenta starts to form. Cells from the placenta (trophoblasts) invade into the uterine mucosa in order to open up maternal uterine arteries to ensure an adequate supply of blood to the developing fetus. The trophoblasts have a unique immunological phenotype compared to most cells especially with regard to their expression of major histocompatibility complex (MHC) antigens. On the other side of the interaction, the uterine mucosa (endometrium) differentiates in preparation for implantation. One of the changes that takes place is the appearance in the endometrium of a large number of maternal leukocytes in the final part of the menstrual cycle. If pregnancy ensues, these leukocytes continue to increase in number and are found in close contact with trophoblasts. The composition of this population of maternal immune cells is unusual compared to that seen at other mucosal sites. A lot of research has focused on whether maternal T-cell responses are suppressed or modified during pregnancy. Research has also concentrated on the specialized uterine natural killer (NK) cells, which are found in the decidua in large numbers during early pregnancy. These uterine NK cells have been shown to express receptors for trophoblast MHC antigens, but their role in pregnancy is still mysterious. The purpose of this review is to give an overview of what is known about the immunology at the implantation site and also to provide an update of some of the most recent findings in this field.

The long-term effect of clobazam as adjunctive therapy in epilepsy

Thirty drug-resistant epilepsy patients were given 20-30 mg of clobazam in addition to their other anticonvulsants and followed up for 2-3 years in an open-ended study. Fit frequency was markedly reduced in 43% of patients, few side effects occurred and psychological parameters including the Crown-Crisp questionnaire, showed improvement. It therefore seems that clobazam is a useful additional drug added to conventional anticonvulsant regimes.

On the anticonvulsant and psychotropic properties of clobazam--a preliminary study

Preliminary studies of patients who had brain damage, intractable epilepsy, and mental subnormality showed that clobazam in small doses (20 to 30 mg/day) was beneficial, and indicated that a more detailed investigation was worthwhile. In this study, 30 patients were followed up for at least 18 months in a continuing open-ended study. Fit frequency was found to be markedly reduced, few side effects have occurred, and the visual analogue scales and the Middlesex Hospital Questionnaire have shown improvement. "Breakthrough" has not been a problem at the dose level of 20 to 30 mg/day when given in addition to conventional anticonvulsant regimes, usually carbamazepine, phenytoin, or valproate. In the meanwhile, other psychosocial problems (for example, employment and marital problems) have improved. It therefore seems that clobazam is a useful additional drug in conventional anticonvulsant regimes.

Stress and epilepsy: the value of a benzodiazepine--lorazepam

Twenty four patients with drug resistant epilepsy were given lorazepam and placebo added to their pre-existing drug regime. With lorazepam there was a significant reduction in seizures, especially in those with focal and partial complex attacks. The drug proved effective whether or not the patients regarded stress as a trigger to their seizures, but on the Middlesex Hospital Questionnaire there were differences between those with high and low scores.

Lorazepam: its effect on the EEG paroxysmal activity in patients with epilepsy

Benzodiazepines given intravenously abort status epilepticus, and abolish paroxysmal EEG discharges. The study reported concerns the effect of small doses (about 1 mg) of lorazepam on these EEG changes, assessed visually, in the resting record, as well as during overbreathing and photic stimulation. Thirty patients were examined, approximately half had primary generalised and the remainder focal epilepsy. All showed rapid reduction of paroxysms in the first few minutes following injection. This occurred faster and was much more persistent for the generalised than for the focal group. The effect of chronic oral administration of lorazepam in these patients is under investigation.

Comparison of two types of visual evoked potentials: pattern reversal and eye movement (lambda)

The averaged visual evoked potentials of 10 normal subjects were studied either with eyes fixated while a chequerboard reversed or when they moved their eyes across the stationary chequerboard. The resulting occipital potentials averaged using a computer of averaged transients were discrepant for the 2 conditions. The latency of the P100 component was similar allowing for the difference in latency in the computer triggering system but the resulting wave forms were different. There was a prominent negative component preceding the P100 in the lambda response and a prominent negative component following the P100 for the pattern shift. The possible reasons for the findings are discussed.

Platelet monoamine oxidase activity in epilepsy

The platelet monoamine oxidase activity (MAO) of 33 patients with epilepsy was compared with a group of neurological patients and a group of normal control subjects. We found that the MAO activity was increased significantly in the epileptic group when compared with the normal. This was not related to anticonvulsant medication. These results could be explained by the effect of epilepsy or anticonvulsant medication on the maturation of platelets.

Effect of tyramine in migraine: a double-blind study

The incidence of headache and changes in the EEG after tyramine were studied in 25 migrainous patients in a double-blind placebo-controlled investigation. There were three groups of patients: the first had migraine alone, the second had migraine and epilepsy, and the third had migraine which was precipitated by food substances containing tyramine. Psychological tests showed that all the patients were more neurotic, more introverted, and more obsessional than normal subjects. Headache occurred in 12 of 50 patient sessions and 10 of these occurred in the group with dietary precipitated migraine. In this group, however, headache followed tyramine alone in only two patients. The remaining eight headaches occurred in two patients after placebo alone, and in three after both test capsules. The EEG was activated after tyramine, but not after placebo, in 11 of the 15 patients with migraine and epilepsy, and dietary precipitated migraine. This effect was observed, however, in only two of the 10 patients with classical migraine alone. There was no relation between the occurrence of headache and EEG activation. Although there was no significant relationship between tyramine ingestion and the occurrence of headache, the EEG changes observed during the study support the hypothesis that tyramine has an action on the central nervous system in some migrainous subjects.

Opposite responding in two sense modalities

Monkeys were trained to respond in one way to a pair of solid objects when discrimination was by touch; in the opposite way, when by vision. These opposite habits are formed independently and can be used concurrently. The finding suggests that the neural systems responsible for tactile and visual learning are separate, even with a single pair of objects.