Age-related natural fertility outcomes in women over 35 years: a systematic review and individual participant data meta-analysis.

STUDY QUESTION: What is the rate of natural conception leading to ongoing pregnancy or livebirth over 6-12 months for infertile women of age ≥35 years? SUMMARY ANSWER: Natural conception rates were still clinically relevant in women aged 35 years and above and were significantly higher in women with unexplained infertility compared to those with other diagnoses. WHAT IS KNOWN ALREADY: In recent years, increasing numbers of women have attempted to conceive at a later age, resulting in a commensurate increase in the need for ART. However, there is a lack of data on natural fertility outcomes (i.e. no interventions) in women with increasing age. STUDY DESIGN, SIZE, DURATION: A systematic review with individual participant data (IPD) meta-analysis was carried out. PubMed, MEDLINE, EMBASE, the Cochrane Library, clinicaltrials.gov were searched until 1 July 2018 including search terms 'fertility service', 'waiting list', 'treatment-independent' and 'spontaneous conception'. Language restrictions were not imposed. PARTICIPANTS/MATERIALS, SETTING, METHODS: Inclusion criteria were studies (at least partly) reporting on infertile couples with female partner of age ≥35 years who attended fertility services, underwent fertility workup (e.g. history, semen analysis, tubal status and ovulation status) and were exposed to natural conception (e.g. independent of treatment such as IVF, ovulation induction and tubal surgery). Studies that exclusively studied only one infertility diagnosis, without including other women presenting to infertility services for other causes of infertility, were excluded. For studies that met the inclusion criteria, study authors were contacted to provide IPD, after which fertility outcomes for women of age ≥35 years were retrieved. Time to pregnancy or livebirth and the effect of increasing age on fertility outcomes after adjustment for other prognostic factors were analysed. Quality of studies was graded with the Newcastle-Ottawa Scale (non-randomised controlled trials (RCTs)) or the Cochrane Risk of Bias tool (for RCTs). MAIN RESULTS AND THE ROLE OF CHANCE: We included nine studies (seven cohort studies and two RCTs) (n = 4379 women of at least age 35 years), with the observed composite primary outcome of ongoing pregnancy or livebirth occurring in 429 women (9.8%) over a median follow-up of 5 months (25th to 75th percentile: 2.5-8.5 months). Studies were of moderate to high quality. The probability of natural conception significantly decreased with any diagnosis of infertility, when compared with unexplained infertility. We found non-linear effects of female age and duration of infertility on ongoing pregnancy and tabulated the predicted probabilities for unexplained infertile women aged 35-42 years with either primary or secondary infertility and with a duration of infertility from 1 to 6 years. For a 35-year-old woman with 2 years of primary unexplained infertility, the predicted probability of natural conception leading to ongoing pregnancy or livebirth was 0.15 (95% CI 0.11-0.19) after 6 months and 0.24 (95% CI 0.17-0.30) after 12 months. For a 42-year-old woman, this decreased to 0.08 (95% CI 0.04-0.11) after 6 months and 0.13 (95% CI 0.07-0.18) after 12 months. LIMITATIONS, REASONS FOR CAUTION: In the studies selected, there were different study designs, recruitment strategies in different centres, protocols and countries and different methods of assessment of infertility. Data were limited for women above the age of 40 years. WIDER IMPLICATIONS OF THE FINDINGS: Women attending fertility services should be encouraged to pursue natural conception while waiting for treatment to commence and after treatment if it is unsuccessful. Our results may aid in counselling women, and, in particular, for those with unexplained infertility. STUDY FUNDING/COMPETING INTEREST(S): S.J.C. received funding from the University of Adelaide Summer Research Scholarship. B.W.M. is supported by a NHMRC Investigator grant (GNT1176437), B.W.M. reports consultancy for ObsEva, Merck, Merck KGaA, iGenomix and Guerbet. B.W.M. reports research support by Merck and Guerbet. PROSPERO REGISTRATION NUMBER: CRD42018096552.

Characterization of the bionano interface and mapping extrinsic interactions of the corona of nanomaterials.

Nanoparticles in physiological environments are known to selectively adsorb proteins and other biomolecules forming a tightly bound biomolecular 'corona' on their surface. Where the exchange times of the proteins are sufficiently long, it is believed that the protein corona constitutes the particle identity in biological milieu. Here we show that proteins in the corona retain their functional characteristics and can specifically bind to cognate proteins on arrays of thousands of immobilised human proteins. The biological identity of the nanomaterial is seen to be specific to the blood plasma concentration in which they are exposed. We show that the resulting in situ nanoparticle interactome is dependent on the protein concentration in plasma, with the emergence of a small number of dominant protein-protein interactions. These interactions are those driven by proteins that are adsorbed onto the particle surface and whose binding epitopes are subsequently expressed or presented suitably on the particle surface. We suggest that, since specific tailored protein arrays for target systems and organs can be designed, their use may be an important element in an overall study of the biomolecular corona.

Effects of assisted hatching method and age on implantation rates of IVF and ICSI.

The objective of this study was to investigate whether a change in assisted hatching (AH) technique from total to partial penetration of the zona pellucida improved the outcome of IVF and intracytoplasmic sperm injection cycles where AH was indicated. This was an observational study conducted from the beginning of January 2000 to the end of April 2005. Total AH was performed in 312 cycles, while partial AH was performed in 592 cycles. In women of all ages, implantation, clinical pregnancy and live birth rates were higher in the partial AH group than in the total AH group (12.6 versus 7.2%, P = 0.0001; 22.3 versus 15.7%, P = 0.02; 18.2 versus 12.5%, P = 0.03 respectively). The benefit of partial AH was most marked in women under 38 years old (i.e. the recurrent implantation failure group). The authors conclude that partial AH is associated with higher implantation and pregnancy rates than total AH, especially in women under 38 years old who suffer from recurrent implantation failure.

Likelihood of natural conception following treatment by IVF.

PURPOSE: To predict the ongoing likelihood of natural conception, when a couple has ceased to try to conceive by assisted conception. METHODS: A postal questionnaire survey obtained information on further attempts to conceive and have a baby, either without treatment or by treatment elsewhere. RESULTS: From a response rate of 44%, there were 116 couples who fulfilled the study criteria. The data presented are based on this group. The overall likelihood of conception was 18%. Cumulative results were analysed up to 3 years following treatment. Univariate analysis showed that likelihood of conception was affected by infertility diagnosis (p = 0.024), woman's age (> 38 years; p < 0.005) (negatively) and duration of infertility (< 3 years; p < 0.005) (positively), while primary infertility did not. Effects of diagnosis and infertility duration were confirmed by multivariable analysis, controlling for age and primary infertility. These latter variables had no independent effect. CONCLUSION: The likelihood of natural conception following IVF treatment was determined by duration of infertility and diagnosis; tubal disease in particular was associated with a very poor likelihood of natural conception.

Higher cortisol:cortisone ratios in the preovulatory follicle of completely unstimulated IVF cycles indicate oocytes with increased pregnancy potential.

BACKGROUND: Conception following gonadotrophin-stimulated IVF and embryo transfer has been associated with a higher intrafollicular cortisol:cortisone ratio and decreased metabolism of cortisol to cortisone. The role of glucocorticoids in human oocyte maturation is not fully understood, but active glucocorticoid (cortisol) may be important. This study relates intrafollicular cortisol and cortisone concentrations to oocyte fertilization and embryo implantation in unstimulated cycles. METHODS: Patients aged <40 years with favourable sperm underwent unstimulated IVF-embryo transfer. Study 1 related intrafollicular cortisol levels to oocyte and IVF outcome: (i) fertilized, pregnant (n = 9); (ii) fertilized, not pregnant (n = 21); and (iii) unfertilized (n = 12). Study 2 was a case-control study of 27 patients (same outcome groups of equal size) which measured intrafollicular cortisol, cortisone and the cortisol:cortisone ratio. RESULTS: Conception cycles demonstrated higher cortisol concentrations compared with the fertilized group (study 1) [median (95% confidence interval): 299 (249-330) versus 227 nmol/l (185-261); P < 0.05] and higher cortisol:cortisone ratios when compared with the unfertilized group (study 2) [7.38 (5.23-9.19) versus 3.56 (1.75-7.46) respectively; P = 0.02]. Of the women with cortisol:cortisone ratios greater than the outcome independent mean of 5.90, 58% conceived compared with only 13% with ratios <5.90 (P < 0.02). CONCLUSION: Higher cortisol:cortisone ratios in conception cycles suggest that active glucocorticoid may be important for final oocyte maturation and embryo implantation in unstimulated cycles.

Big-screen laparoscopic surgery.

Significant advances in fiberoptic and digital technology for laparoscopic surgery have been made over the past decade. One area that appears to be overlooked in this field is the advancement in the display of the image during laparoscopic surgery. The authors describe the use of digital video-cinema equipment as a simple and effective technique that enhances the projection of the surgical view. This method has been found to be visually more comfortable, aiding the surgical procedure, and extremely useful as a teaching tool.

What is the optimal medical management of infertility and minor endometriosis? Analysis and future prospects.

By asking the question 'What is the optimal medical management of infertility and minor endometriosis?', it is assumed that endometriosis has a detrimental effect on fertility. The published data suggest that oocyte dysfunction may contribute to infertility associated with endometriosis. This is expressed as a reduction in fertilization and implantation rates; implantation rates to a lesser extent, though still significant. Other evidence for oocyte dysfunction exists, not all of which is consistent. Suppression of ovulation and menstruation to treat endometriosis-associated infertility is not effective. However, ovulation induction, perhaps with intrauterine insemination, does result in pregnancy rates higher than in control cycles, while stimulated IVF success rates are equivalent to those of other diagnostic groups. For the future, angiogenesis is critical to the support of endometriotic deposits and targeted therapies are promised; their role in improving fertility has not yet been explored.

Total cortisol levels are reduced in the periovulatory follicle of infertile women with minimal-mild endometriosis.

PROBLEM: To measure and compare concentrations of total and free glucocorticoids with oocyte fertilizing capacity in the follicular fluid (FF) of women with minimal-mild endometriosis and tubal damage. METHOD OF STUDY: Follicular fluid was collected from individual periovulatory follicles during oocyte retrieval for in vitro fertilization (IVF) in natural cycles. Total and free levels of cortisol and cortisone were measured using specific radioimmunoassays after chloroform extraction. RESULTS: Cortisol concentrations in women with minimal-mild endometriosis were significantly lower compared with controls (women with tubal infective damage) (258 versus 328 nmol/L, P < 0.02). There was no correlation between total or free concentrations of cortisol or cortisone and the fertilization capacity of the oocyte. CONCLUSIONS: Total cortisol levels are lower in the follicles of women with endometriosis. Our findings provide further evidence of follicular dysfunction contributing to the subfertility associated with minimal-mild endometriosis.

A human cDNA expression library in yeast enriched for open reading frames.

We developed a high-throughput technique for the generation of cDNA libraries in the yeast Saccharomyces cerevisiae which enables the selection of cloned cDNA inserts containing open reading frames (ORFs). For direct screening of random-primed cDNA libraries, we have constructed a yeast shuttle/expression vector, the so-called ORF vector pYEXTSH3, which allows the enriched growth of protein expression clones. The selection system is based on the HIS3 marker gene fused to the C terminus of the cDNA insert. The cDNAs cloned in-frame result in histidine prototrophic yeast cells growing on minimal medium, whereas clones bearing the vector without insert or out-of-frame inserts should not grow on this medium. A randomly primed cDNA library from human fetal brain tissue was cloned in this novel vector, and using robot technology the selected clones were arrayed in microtiter plates and were analyzed by sequencing and for protein expression. In the constructed cDNA expression library, about 60% of clones bear an insert in the correct reading frame. In comparison to unselected libraries it was possible to increase the clones with inserts in the correct reading frame more than fourfold, from 14% to 60%. With the expression system described here, we could avoid time-consuming and costly techniques for identification of clones expressing protein by using antibody screening on high-density filters and subsequently rearraying the selected clones in a new "daughter" library. The advantage of this ORF vector is that, in a one-step screening procedure, it allows the generation of expression libraries enriched for clones with correct reading frames as sources of recombinant proteins.

Haematuria presenting six years after a pelvic fracture.

Pelvic fractures are frequently associated with injuries to the lower genitourinary tract. However, most described injuries are noted at the time the fracture is sustained. We describe the case of a 63-year-old man who presented with haematuria 6 years after sustaining an 'open-book'-type pelvic fracture.

Protein and antibody arrays and their medical applications.

Many new gene products are being discovered by large-scale genomics and proteomics strategies, the challenge is now to develop high throughput approaches to systematically analyse these proteins and to assign a biological function to them. Having access to these gene products as recombinantly expressed proteins, would allow them to be robotically arrayed to generate protein chips. Other applications include using these proteins for the generation of specific antibodies, which can also be arrayed to produce antibody chips. The availability of such protein and antibody arrays would facilitate the simultaneous analysis of thousands of interactions within a single experiment. This chapter will focus on current strategies used to generate protein and antibody arrays and their current applications in biological research, medicine and diagnostics. The shortcomings of these approaches, the developments required, as well as the potential applications of protein and antibody arrays will be discussed.

Medical education with the Internet: a pilot training programme in reproductive medicine.

Following a detailed information technology survey in the South West Deanery, an Internet educational programme in reproductive medicine was constructed, delivered and assessed. The course followed a problem-based approach using case studies, using an education website and electronic mail (e-mail) to communicate between trainees and trainers. Independent evaluation revealed a high level of satisfaction for both trainees and trainers with an increase in trainees' confidence to deal with patients following the course. This study suggests that the Internet may be used effectively to deliver postgraduate medical education, if the training programme is designed appropriately to computer infrastructure and the computer literacy of the users.

Direct ovarian effects and safety aspects of GnRH agonists and antagonists.

In in-vitro fertilization programmes, gonadotrophin releasing hormone (GnRH) agonists are now routinely used in order to prevent the undesired pre-ovulatory spontaneous luteinizing hormone surge. The first publications are now appearing in which GnRH antagonists are used with the same purpose. More attention should be addressed to the safety aspects of these drugs. This review aims to summarize studies on direct ovarian effects of GnRH agonists and GnRH antagonists in non-primates and primates with respect to the functional and morphological aspects in-vitro as well as in-vivo. We conclude that there is a wide variety of functional and morphological effects of GnRH analogues on the ovary. The sometimes paradoxical effects indicate that a variety of factors may be involved in the various processes. Those factors are: (i) the type and dose of the analogue, (ii) the different regimens of administration, (iii) ovarian status at the time of exposure, (iv) ovarian cell types in in-vitro systems, (v) hormonal pre-treatment of these cultures, (vi) the type of hormonal stimulation added to the in-vitro culture, (vii) further methodological differences in the experiments and finally (viii) physiological variations in GnRH receptor abundance which depends on species and/or timing in the cycle. With the increasing number of patients using GnRH analogues in assisted reproduction treatments, there will be an increasing number of pregnancies exposed to these drugs. So far, there does not appear to be an increased risk of birth defects or pregnancy wastage in human pregnancies exposed to daily low-dose GnRH agonist therapy in the first weeks of gestation.

Expected contribution to serum oestradiol from individual ovarian follicles in unstimulated cycles.

Data relating serum oestradiol concentration to follicle size in unstimulated cycles are lacking. We provide precise data on serum concentrations expected for any follicle diameter (FD) in the mid- to late follicular phase. Infertile women (n = 35) with apparently normal ovulatory cycles were studied in detail in 128 unstimulated monofollicular cycles leading to IVF. Using mathematical modelling to account for repeated cycles in the same woman, the relationship between serum oestradiol and FD was explored and reference ranges for serum oestradiol at individual FD were calculated. Serum oestradiol concentrations [number of patients, geometric mean, 95% confidence interval (CI)] at the onset of the LH surge were higher in 'fertilized' cycles (73, 1279, 1180-1378 pmol/l) compared with 'unfertilized' cycles (31, 1055, 929-1197 pmol/l, P: = 0.008) and 'no oocyte' cycles (24, 1064, 922-1227 pmol/l, P: = 0.03) respectively. In 'fertilized' cycles, oestradiol concentrations rose exponentially with FD and for each size of follicle the oestradiol distribution was skewed. Functional oocyte competence varied in apparently normal ovulatory cycles and was correlated with pre-ovulatory serum oestradiol but not FD. Serum oestradiol varies within wide limits for maturing follicles of any given diameter prior to the onset of the LH surge.

Inhibin A, inhibin B and activin A in follicular fluid of infertile women with tubal damage, unexplained infertility and emdometriosis.

PROBLEM: To measure and compare concentrations of inhibin A, inhibin B, activin A and oestradiol in the follicular fluid of women with endometriosis, tubal damage and unexplained infertility with oocyte quality and fertilising capacity. Also, to assess whether impaired follicular function in women with endometriosis might be related to altered inhibin or activin concentrations and whether this correlated. METHOD OF STUDY: Follicular fluids were collected from individual follicles during oocyte retrieval for in vitro fertilisation (IVF) in natural cycles. Inhibin A, inhibin B and activin A were measured using two-site enzyme immunoassay, and oestradiol was assayed by fluoro-immunometric method. RESULTS: Follicular fluid inhibin A levels were found to be significantly higher in women with endometriosis. Inhibin A was directly correlated with follicle size. There was no correlation between the levels of inhibin A, inhibin B, activin A and oocyte quality or fertilising capacity in the three groups of women. CONCLUSIONS: Follicular fluid concentration of inhibin A is elevated in follicles of women with endometriosis and is positively correlated with follicle maturation. However, we were unable to demonstrate any association between the follicular fluid concentrations of inhibin A, inhibin B, activin A or oestradiol and the quality and fertilisation capacity of oocytes in women with tubal damage, unexplained infertility or endometriosis.

Pituitary-ovarian dysfunction and endometriosis.

Significant association between endometriosis, including minor endometriosis, and infertility (or strictly subfertility) is shown by prevalence studies, but a causal relationship has not been established. This review focuses on evidence for pituitary-ovarian dysfunction as a cause for the subfertility. A methodological problem is lack of fertile controls with endometriosis. Group comparison with tubal infertility cases as controls have demonstrated: impaired follicular growth, reduction in circulating oestradiol concentrations during the pre-ovulatory phase and of oestradiol and progesterone during the early luteal phase, and disturbed luteinizing hormone (LH) surge patterns. Reduction in LH concentrations in pre-ovulatory follicular fluid has also been found, and granulosa cells collected at the same time have demonstrated impaired steroidogenic capacity in vitro, but these were not consistently proven findings. Pooled data from published studies show significantly reduced oocyte fertilization rates (49%) compared with controls (69%), even after maximal stimulation with exogenous follicle stimulating hormone (FSH) and human chorionic gonadotrophin (HCG) (54 versus 69%). The implantation rate is also slightly (though significantly) reduced (11 versus 13%). The findings suggest an inherent disorder of follicular function, with LH surge impairment probably being a secondary phenomenon. The resulting reduction in the chance of fertilization of the oocyte would contribute substantially to the subfertility associated with endometriosis. It seems that the benefit of in-vitro fertilization is gained through the excessive number of oocytes obtained by stimulation.