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Effects of photoevaporation on protoplanetary disc ‘isochrones’

Protoplanetary discs are the site of star and planet formation, and their evolution and consequent dispersal deeply affect the formation of planetary systems. In the standard scenario they evolve on time-scales similar to Myr due to the viscous transport of angular momentum. The analytical self-similar solution for their evolution predicts specific disc isochrones in the accretion rate-disc mass plane. However, photoevaporation by radiation emitted by the central star is likely to dominate the gas disc dispersal of the innermost region, introducing another (shorter) time-scale for this process. In this paper, we include the effect of internal (X and EUV) photoevaporation on the disc evolution, finding numerical solutions for a population of protoplanetary discs. Our models naturally reproduce the expected quick dispersal of the inner region of discs when their accretion rates match the rate of photoevaporative mass loss, in line with previous studies. We find that photoevaporation preferentially removes the lightest discs in the sample. The net result is that, counter-intuitively, photoevaporation increases the average disc mass in the sample, by dispersing the lightest discs. At the same time, photoevaporation also reduces the mass accretion rate by cutting the supply of material from the outer to the inner disc. In a purely viscous framework, this would be interpreted as the result of a longer viscous evolution, leading to an overestimate of the disc age. Our results thus show that photoevaporation is a necessary ingredient to include when interpreting observations of large disc samples with measured mass accretion rates and disc masses. Photoevaporation leaves a characteristic imprint on the shape of the isochrone. Accurate data of the accretion rate-disc mass plane in the low disc mass region therefore give clues on the typical photoevaporation rate

Risk factors for monozygotic twinning after in vitro fertilization : a systematic review and meta-analysis

Objectives: To establish the risk factors for monozygotic twin (MZT) and monochorionic twin (MCT) pregnancies after in vitro fertilization (IVF). Design: Systematic review and meta-analysis. Setting: Not applicable. Patient(s): Women who achieved MZT and non-MZT pregnancies through IVF. Intervention(s): Systematic search of Medline from January 1995 to October 2018 with cross-checking of references from relevant articles in English. Main Outcome Measure(s): Possible risk factors for MZT or MCT pregnancies after IVF, comprising extended embryo culture, insemination method (conventional IVF and intracytoplasmic sperm injection [ICSI]), embryo biopsy for preimplantation genetic testing for aneuploidies or for monogenic/single-gene defects (PGT-A or PGT-M) programs, assisted hatching (AH), oocytes donation, female age, and embryo cryopreservation. Result(s): A total of 40 studies were included. Blastocyst transfer compared with cleavage-stage embryo transfer, and female age <35 years were associated with a statistically significant increase in the MZT and MCT pregnancy rate after IVF: (23 studies, OR 2.16, 95% CI, 1.74\u20132.68, I 2 =78%; 4 studies, OR 1.29; 95% CI, 1.03\u20131.62, I 2 =62%; and 3 studies, OR 1.90, 95% CI, 1.21\u20132.98, I 2 =59%; 2 studies, OR 2.34; 95% CI, 1.69\u20133.23, I 2 =0, respectively). Conventional IVF compared with ICSI and assisted hatching were associated with a statistically significantly increased risk of MZT pregnancy (9 studies, OR 1.19, 95% CI, 1.04\u20131.35, I 2 =0; 16 studies, OR 1.17, 95% CI, 1.09\u20131.27, I 2 =29%, respectively). Embryo biopsy for PGT-A or PGT-M, embryo cryopreservation, and oocytes donation were not associated with MZT pregnancies after IVF. Conclusion(s): Blastocyst transfer is associated with an increased risk of both MZT and MCT pregnancies after IVF. Further evidence is needed to clarify the impact of female age, insemination method and AH on the investigated outcomes

The impact of IVF on deep invasive endometriosis

Objective: Ovarian hyper-stimulation during IVF is associated with a significant raise in serum estrogens and one may expect detrimental effects on estrogen-dependent diseases such as endometriosis. However, available evidence from large case series of affected women performing IVF is generally reassuring with the possible exception of women carrying deep invasive lesions. On this basis we deemed important investigating more in depth whether women with deep invasive endometriosis could be a subgroup at higher risk of recurrence or disease progression during IVF. Study design: Women with endometriosis who underwent IVF and who had a second evaluation after 3\u20136 months from a failed cycle were retrospectively reviewed. The main inclusion criteria were the presence of deep invasive endometriosis and/or a history of surgery for this form of the disease. The primary aim of the study was to determine the frequency of endometriosis-related complications in the interval between the two evaluations. Secondary aims were pain symptoms and lesion size modifications. Results: Eighty-four women were ultimately selected: baseline ultrasound documented deep invasive lesions in 60 of them. One case of possible endometriosis-related complication was recorded, corresponding to a rate of 1.2% (95%: 0.05%\u20135.5%) for the whole cohort and 1.7% (95%CI: 0.08\u20137.6%) for the subgroup of women with ultrasound detected lesions. This rate appears similar to the reported frequency of endometriosis progression in women not receiving IVF. No significant modifications in pain symptoms or lesions size occurred. Conclusions: Women with deep invasive endometriosis who underwent IVF do not seem to be exposed to a substantially increased risk of recurrence/disease progression. Larger evidence from independent groups is however required for a definitive conclusion

The presence of dominant follicles and corpora lutea does not perturb response to controlled ovarian stimulation in random start protocols

The advent of random start protocols to shorten the time needed to store oocytes in women with malignancies has represented an important improvement in the field of fertility preservation. However, Randomized Controlled Trials are difficult to implement in this area and available evidence that supports this approach remains modest. To shed more light on this issue, we compared the follicular development between the ovary carrying the dominant follicle or the corpus luteum and the contralateral resting ovary in 90 women who underwent random start controlled ovarian stimulation (COS). In fact, ovarian response did not differ between the two ovaries. Subgroup analyses according to the phase of the cycle at the initiation of COS, the type of malignancy, the use of letrozole and the magnitude of the ovarian response did not allow to identify any condition showing a difference in the follicular response between the active and the resting ovaries. In conclusion, follicular growth does not seem to be perturbed by the presence of a dominant follicle or a corpus luteum

Fibroids not encroaching the endometrial cavity and IVF success rate : a prospective study

BACKGROUND The impact of fibroids, not encroaching the endometrial cavity, have on the rate of success of IVF is still controversial. Recent meta-analyses suggest a detrimental effect of intramural lesions but not subserosal lesions. However, they also emphasize the need for further evidence. In order to elucidate this, we designed a prospective cohort study to compare the rate of success of IVF in women with and without fibroids. METHODS Exposed women were those with asymptomatic intramural or subserosal fibroids with a diameter below 50 mm and who were selected for IVF. Unexposed women were those free of fibroids, who were matched to cases by age and number of previous IVF cycles. All recruited patients underwent hystero-sonography to rule out intra-cavitary lesions. RESULTS There were 119 cases and 119 controls recruited. The number of clinical pregnancies in women with and without fibroids was 28 (24%) and 22 (19%), respectively (P= 0.43). The adjusted odds ratio (OR) for pregnancy in affected women was 1.38 [95% confidence interval (CI): 0.73-2.60]. The number of deliveries was 22 (18%) and 16 (13%), respectively (P= 0.38). The adjusted OR was 1.45 (95% CI: 0.71-2.94). Similar results emerged when focusing exclusively on women carrying intramural lesions (n= 80 couples). There was no significant relationship between clinical outcome and either the number or size of the fibroids. CONCLUSIONS In asymptomatic patients selected for IVF, small fibroids not encroaching the endometrial cavity did not impact on the rate of success of the procedure

The long pentraxin 3 is a soluble and cell-associated component of the human semen

The long pentraxin 3 (PTX3) is a multifunctional soluble pattern recognition receptor, involved in several processes ranging from innate resistance and inflammation to clearance of apoptotic cells and organization of hyaluronic acid-rich extracellular matrices. PTX3 is also a novel marker in several pathological conditions of infectious, inflammatory, or autoimmune origin. This study was designed to assess whether PTX3 is expressed in the male reproductive tract and whether PTX3 interacts with human spermatozoa influencing their function. Here we show for the first time by immunohistochemistry that PTX3 is expressed in the male genital tract in perivascular connective tissue, in endothelial cells, in the interstitium, and in the cytoplasm of prostatic epithelial glandular cells; PTX3 was detectable in seminal plasma in variable levels, which correlated with the percentage of normal spermatozoa. Moreover, PTX3 binds to spermatozoa, in particular with immotile cells, localizing in the neck and in the subacrosomial region. Finally, recombinant PTX3 did not interfere with sperm motility

Blood cell mitochondrial DNA content and premature ovarian aging

Primary ovarian insufficiency (POI) is a critical fertility defect characterized by an anticipated and silent impairment of the follicular reserve, but its pathogenesis is largely unexplained. The frequent maternal inheritance of POI together with a remarkable dependence of ovarian folliculogenesis upon mitochondrial biogenesis and bioenergetics suggested the possible involvement of a generalized mitochondrial defect. Here, we verified the existence of a significant correlation between blood and ovarian mitochondrial DNA (mtDNA) content in a group of women undergoing ovarian hyperstimulation (OH), and then aimed to verify whether mtDNA content was significantly altered in the blood cells of POI women. We recruited 101 women with an impaired ovarian reserve: 59 women with premature ovarian failure (POF) and 42 poor responders (PR) to OH. A Taqman copy number assay revealed a significant mtDNA depletion (P<0.001) in both POF and PR women in comparison with 43 women of similar age and intact ovarian reserve, or 53 very old women with a previous physiological menopause. No pathogenic variations in the mitochondrial DNA polymerase \u3b3 (POLG) gene were detected in 57 POF or PR women with low blood mtDNA content. In conclusion, blood cell mtDNA depletion is a frequent finding among women with premature ovarian aging, suggesting that a still undetermined but generalized mitochondrial defect may frequently predispose to POI which could then be considered a form of anticipated aging in which the ovarian defect may represent the first manifestation. The determination of mtDNA content in blood may become an useful tool for the POI risk prediction

Impact of endometriosis on obstetric outcome after natural conception: a multicenter Italian study

Purpose To evaluate obstetric outcome in women with endometriosis who conceive naturally and receive standard obstetric care in Italy. Methods Cases were consecutive women with endometriosis managed in eleven Italian referral centers. Controls were women in whom endometriosis was excluded. All women filled in a questionnaire addressing previous natural pregnancies. Marginal logistic regression models were fitted to evaluate the impact of endometriosis on obstetric outcome. A post hoc analysis was performed within the endometriosis group comparing women with severe adenomyosis versus women with absent or mild adenomyosis. Results Three hundred and fifty-five pregnancies in endometriosis group and 741 pregnancies in control group were included. Women with endometriosis had a higher risk of preterm delivery &lt; 34 weeks (6.4% vs 2.8%, OR 2.42, 95% CI 1.22–4.82), preterm delivery &lt; 37 weeks (17.8% vs 9.7%, OR 1.98, 95% CI 1.23–3.19), and neonatal admission to Intensive Care Unit (14.1% vs 7.0%, OR 2.04, 95% CI 1.23–3.36). At post hoc analysis, women with endometriosis and severe adenomyosis had an increased risk of placenta previa (23.1% vs 1.8%, OR 16.68, 95% CI 3.49–79.71), cesarean delivery (84.6% vs 38.9%, OR 8.03, 95% CI 1.69–38.25) and preterm delivery &lt; 34 weeks (23.1% vs 5.7%, OR 5.52, 95% CI 1.38–22.09). Conclusion Women with endometriosis who conceive naturally have increased risk of preterm delivery and neonatal admission to intensive care unit. When severe adenomyosis is coexistent with endometriosis, women may be at increased risk of placenta previa and cesarean delivery. Trial registration Clinical trial registration number: NCT03354793