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Dareen Mattar, Warakorn Cheewasopit, Moafaq Samir, and Phil G Knight
Kisspeptin, a hypothalamic neuropeptide encoded by the KISS1 gene, has a pivotal role in promoting gonadotrophin-releasing hormone secretion in mammals. Kisspeptin and its receptor (KISS1R) are also expressed in certain peripheral tissues including gonads, suggesting intra-gonadal roles. Such actions at the level of the bovine ovary have not been explored previously. The current aims were to determine whether KISS1 and KISS1R are expressed in the bovine ovary and whether kisspeptin or a kisspeptin antagonist can modulate ovarian steroid production by cultured ovarian cells. Granulosa cells (GC) and theca interna cells (TC) were collected from antral follicles (3–18 mm) categorized into five class sizes. Early, mid and regressing corpora lutea (CL) were also collected for RT-qPCR analysis of KISS1 and KISS1R expression. Bovine TC and GC cultured under both non-luteinizing (serum-free) and luteinizing (serum-supplemented) conditions were treated for 4 days with kisspeptin-10 (10– 10–10– 6M) or kisspeptin antagonist (kp234; 10–10–10–6M), alone and in combination with either follicle-stimulating hormone (GC), luteinizing hormone (TC) or forskolin (luteinized GC/TC). Steroid secretion (GC: oestradiol, progesterone; TC: androstenedione, progesterone; luteinized GC/TC: progesterone) was measured by ELISA and viable cell number determined by neutral red uptake assay. KISS1 and KISS1R transcripts were detected in TC, GC and CL with significant differences between follicle categories and CL stages. However, neither kisspeptin-10 nor kisspeptin antagonist affected steroid secretion or viable cell number in any of the four ovarian cell culture models. As such, the hypothesis that kisspeptin has a direct intraovarian role to modulate follicular or luteal steroidogenesis, or cell proliferation/survival, is not supported.
Lay summary
Kisspeptin-producing nerve cells (neurones) in the hypothalamus play a crucial role in controlling the reproductive system. Kisspeptin activates receptors on gonadotrophin-releasing hormone neurones which, in turn, stimulate the pituitary gland to release gonadotrophins. Gonadotrophins act on the gonads (ovaries or testes) to regulate their function (e.g. ovarian follicle development and steroid production). Evidence has emerged in several species that kisspeptin and its receptor are also present in certain peripheral tissues, including the ovaries, suggesting ‘local’ actions. So far, few studies have investigated this. Here, we first show that both kisspeptin and its receptor are expressed by key ovarian cell types of cattle. However, we found that treating cultured bovine theca and granulosa cells with kisspeptin or kisspeptin antagonist did not modify steroid secretion. As such, the hypothesis that kisspeptin has a direct intraovarian role to modulate ovarian steroid production is not supported.
Mohamed Elkalyoubi, Larissa Schindler, and Hena Zaheer
Treatment of sub-fertile women aged ≥ 40 years old (advanced maternal age (AMA)) is challenging. Co-treatment with growth hormone (GH) is suggested to improve reproductive outcomes in poor responders. However, few studies, and with conflicting results, focused on women of AMA. A systematic review and meta-analysis of randomized controlled trials (RCTs) and comparative retrospective trials (CRTs) of GH cotreatment in AMA women undergoing in vitro fertilization or intracytoplasmic injection treatment using their autologous oocytes was performed. The search included studies published in English up to the end of 2021. The primary outcome was the clinical pregnancy rate per embryo transfer. Secondary outcomes were the number of mature and retrieved oocytes and the rate of live birth. A total of 406 studies were found. The final analysis included 3 RCTs and 4 CRTs with 481 patients who used GH and 400 patients who did not. Clinical pregnancy and live birth rates were significantly higher in the GH cotreatment group compared to the placebo as well as the group without GH co-treatment, (odds ratio (OR): 2.2; 95% CI: 1.34–3.61 and OR: 4.12; 95% CI: 1.82–9.32, respectively). Intriguingly, the subgroup analysis showed that poor-responder patients did not benefit from co-treatment with GH. There were no statistically significant differences in the number of mature or retrieved oocytes. GH cotreatment in a subgroup of women of AMA improves clinical pregnancy and live birth per fresh embryo transfer. However, this conclusion must be taken with caution and further research is needed. The review is registered in the PROSPERO database (www.crd.york.ac.uk/prospero/; CRD42021252618).
Lay summary
Women over 40 years undergoing in vitro fertilization (IVF) treatment commonly require high doses of injectable medications to stimulate their ovaries. Co-treatment with growth hormone (GH) has been shown to enhance the ovarian response and improve the outcome. The investigators found seven studies that compared 881 women over 40 years of age who had undergone IVF treatment with or without GH cotreatment. Statistical analysis of data from these studies showed that some of these women may benefit from adding a GH to their ovarian stimulation medications. The benefit was evident in those with good ovarian reserve. Women over 40 years with a good ovarian reserve can increase their chance of pregnancy by 4–20% when using GH during ovarian stimulation. However, this finding requires confirmation in a well-designed study with large sample size. Furthermore, the optimal dose, regimen, safety, and cost-effectiveness of GH cotreatment should be clarified.
Bethany Chung, Charlotte Greene, Alice Pearson, Lisa M Starrs, and W Colin Duncan
Lay Summary
During the COVID-19 pandemic, the public delayed seeking medical help, which may have affected the impact of having an ectopic pregnancy. An ectopic pregnancy is when pregnancy tissue grows outside its normal position in the womb, and it can be life-threatening. It can be treated by non-surgical or surgical options, and any delay in seeking help can reduce the options for treatment and increase the need for more urgent management. We wanted to assess whether there were differences in the presentation and management of ectopic pregnancies in a major teaching hospital between 2019 (pre-COVID-19) and 2021 (COVID-19 period). We found that the pandemic did not cause a delay in seeking medical help or cause worse outcomes. In fact, immediate surgical treatment and time in the hospital were less during COVID-19, perhaps because of a desire to avoid admission to hospital. One outcome of COVID-19 is reassurance that we can safely use more non-surgical treatments for ectopic pregnancies.
Charvi Kanodia, Michael P Rimmer, Kathleen Duffin, and Rod T Mitchell
Lay summary
Men and boys with cancer treated with chemotherapy are known to have reduced fertility following their treatment. This is because some chemotherapy drugs can damage the cells in the testicles that make sperm. This study found there is limited information available on the effect of one group of chemotherapy drugs, called taxanes, on testicular function and fertility. More studies are needed to aid clinicians in advising patients on how this taxane-based chemotherapy may affect their future fertility.
Jennifer Dabel, Florian Schneider, Joachim Wistuba, Sabine Kliesch, Stefan Schlatt, and Nina Neuhaus
Objective
Germ cells of transwomen are affected by gender-affirming hormone therapy (GAHT). Fertility will be lost after surgical intervention; thereby, fertility preservation becomes an increasingly imortant topic. This study investigated if the absolute number of spermatogonia in transwomen is comparable at the time of gender-affirming surgery (GAS) to that in pre-pubertal boys.
Methods
We carried out a retrospective study of testicular tissues from 25 selected subjects, which had undergone a comparable sex hormone therapy regimen using cyproterone acetate (10 or 12.5 mg) and estrogens. As controls, testicular biopsies of five cisgender adult men (aged 35–48 years) and five pre-/pubertal boys (5–14 years) were included. Testicular tissues were immunohistochemically stained for MAGE A4-positive cells, the most advanced germ cell type. The number of spermatogonia per area was assessed. Clinical values and serum hormone values for FSH, LH, testosterone, free testosterone, estradiol and prolactin were determined on the day of GAS for correlation analyses.
Results
Round spermatids were the most advanced germ cell type in 3 subjects, 5 had an arrest at spermatocyte stage, while 17 showed a spermatogonial arrest. On average, testicular tissues of transwomen contained 25.15 spermatogonia/mm3, a number that was significantly reduced compared to the two control groups (P < 0.01, adult 80.65 spermatogonia/mm3 and pre-/pubertal boys 78.55 spermatogonia/mm3). Linear regression analysis revealed that testes with higher weight and high LH contained more spermatogonia.
Conclusion
Irrespective of treatment dose or duration, spermatogenesis was impaired. Spermatogonial numbers were significantly reduced in transwomen compared to the control groups.
Lay summary
When transwomen go through treatment to confirm their gender, their germ cells are affected. They lose their fertility after surgery, so fertility preservation becomes an important topic. We carried out a study looking at tissue from testes of 25 people who had been through the same sex hormone therapy until surgery. Blood samples were also taken. As controls, samples were taken from the testes of cisgender boys and adult men. On average, the samples from the testes of transwomen contained a smaller number of early sperm cells compared to the two control groups. Regardless of the dose or length of hormone treatment, the fertility of transwomen was significantly reduced so that counseling about fertility preservation should be offered before hormone therapy.
L C Morley, M Debant, H J Gaunt, N A B Simpson, and D J Beech
Lay summary
Friction caused by blood flowing across cells that line blood vessels (endothelial cells) activates sensors of mechanical force. This produces nitric oxide (NO) which widens placental blood vessels, enabling more blood flow to the baby. This study sought to determine whether the mechanical sensor, Piezo1, is important for NO production in fetoplacental endothelial cells (FpECs) and whether the steps in this pathway are different in small for gestational age (SGA) babies, where placental blood flow is often altered. We showed that in healthy FpECs, blood flow increased NO signalling. We suggest that in SGA babies, FpECs have an increase in baseline levels of NO signalling, suggestive of a compensatory drive. Treating healthy and SGA cells with a Piezo1 chemical activator, Yoda1, upregulated NO signalling. This shows that Piezo1 is linked to NO and that in SGA, FpECs have the capacity to further increase NO. Further research will establish whether Piezo1 enhancement leads to increased blood flow in the placenta. If so, Piezo1 could be a new target for developing treatments to prevent poor growth of babies in the womb.
Tsafrir S Kolatt, Yoel Shufaro, Shlomo Mashiach, Bernard Czernobilsky, Sarit Aviel-Ronen, Liat Apel-Sarid, Mazal Dahan, and Yuval Or
Graphical abstract
Abstract
Background
The distribution of the blood vessel network at any point in time in any body tissue may provide valuable information with regard to the tissue condition, whether it is in a growth, declining or recovery phase as well as giving insights as to its angiogenesis functionality. The blood vessel three-dimensional network of the endometrium goes through a process of change over a relatively short period of 4 weeks on average. It is well accepted that angiogenesis within the endometrium is closely related to the success or failure of the implantation of the embryo.
Objective and rationale
Our study aims to present a method to follow the three-dimensional evolution of the superficial blood vessel distribution in the endometrium throughout the uterine cycle.
Method
This method utilizes differences in the observed broadband colors of the blood vessels in order to assess their depth coordinate below the endometrial tissue surface. We implemented the method using microscopic images of fresh, ex vivo, endometrial samples of different cycle days to obtain the statistical evolution track of the superficial blood vessel population in both human and animal (swine) samples.
Outcomes
In human samples, we observed a systematic and consistent trend in the blood vessel diameter distribution at different tissue depths. We demonstrate that the magnitude of this trend evolves throughout the course of the female cycle.
Wider implications
This method has the potential to further our understanding of the mechanisms of angiogenesis in tissues other than the endometrium. We propose that this method may also contribute to more precise endometrial dating and may assist in more accurate determination of embryo transfer timing within in vitro fertilization treatments.
Lay summary
The inner lining tissue of the womb (uterus) is called the endometrium, and it undergoes significant changes during the menstrual cycle.
The endometrium blood vessel network goes through rapid changes during the cycle.
We have developed a new method to measure this through surface imaging of the endometrium.
We use samples of endometrial tissues collected at different dates in the cycle to show how useful this method is in evaluating the development of the endometrium.
The method may also be used to investigate different processes of generating new blood vessels and may help to support dating the development of the endometrium.
Our work offers a non-invasive or minimally invasive method which reveals the three-dimensional blood vessel network and may be used to help in a variety of diagnoses. For example, this method may be used to see how receptive the uterus is during in vitro fertilization treatment.
Yorain Sri Ranjan, Nida Ziauddeen, Beth Stuart, Nisreen A Alwan, and Ying Cheong
Graphical Abstract
Abstract
Endometriosis is a chronic and debilitating condition which can affect the entire reproductive life course of women with a potentially detrimental effect on pregnancy. Pregnancy (and increasing parity) can affect endometriosis by modulating disease severity and suppressing symptoms. Multiparous women could be less likely to suffer from endometriosis-related pregnancy complications than primiparous women. We aimed to systematically review the evidence examining the role of parity in the relationship between pregnancy outcomes and endometriosis. A systematic search of MEDLINE, EMBASE, CINAHL, Web of Science, and Cochrane Library was performed from inception to May 2022. We searched for experimental and observational studies. Grading of Recommendations, Assessment, Development, and Evaluation was used to assess the quality of evidence with the risk of bias in non-randomised studies of interventions tool incorporated. Eleven studies were included in the meta-analysis. Primiparous women with endometriosis had almost double the risk of hypertensive disorders of pregnancy (OR: 1.99, 95% CI: 1.50–2.63, P < 0.001) compared to multiparous women with endometriosis. Primiparous women with endometriosis were at significantly increased risk of preterm delivery, caesarean delivery, and placenta praevia compared to primiparous women without endometriosis. There were no significant differences in outcomes when multiparous women with endometriosis were compared to multiparous women without endometriosis. There is limited evidence to suggest that primiparous women with endometriosis may be at higher risk of adverse pregnancy outcomes compared to multiparous women. The modulatory role of parity in the pathophysiology of endometriosis and its impact on pregnancy outcomes should be investigated.
Lay summary
Endometriosis can adversely affect pregnancy and cause complications that can affect both mother and baby. The severity and symptoms of endometriosis are lessened in pregnancy and with increasing births. Women who have previously given birth could experience fewer pregnancy complications than women giving birth for the first time. We reviewed the literature to compare pregnancy outcomes in women with endometriosis by whether they had given birth before or not. Our review included 11 studies. More women with endometriosis giving birth for the first time had blood pressure disorders in pregnancy than women with endometriosis who had given birth before. First-time mothers with endometriosis tended to have a baby born early, caesarean delivery, and an abnormally located placenta compared to those without endometriosis. This study supports the theory that women with endometriosis in their first pregnancy are at higher risk of complications and may benefit from additional monitoring.
G Hughes and S Martins da Silva
Sperm cryopreservation for men with severely impaired spermatogenesis is one of the commonest reasons for short-term sperm storage, usually in advance of fertility treatment. Cryopreservation is generally very effective, although not all spermatozoa survive the process of freezing and thawing. This review considers various aspects of freezing sperm, including an overview of methods, appropriate use of cryoprotectants and practical considerations, as well as oxidative stress and mechanisms of cell cryodamage.
Lay summary
Cryopreservation involves freezing of cells or tissues to preserve them for future use. Sperm cryopreservation for men with a very low sperm count is one of the commonest reasons for short-term sperm storage, usually in advance of fertility treatment. Cryopreservation is generally very effective, although not all sperm cells survive the process of freezing and thawing. This review covers various aspects of freezing sperm, including consideration of methods used and mechanisms of cell damage.
