Anna Carby

Imperial College Healthcare NHS Trust, Londinium, England, United Kingdom

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Publications (5)80.24 Total impact

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    ABSTRACT: To review currently available options in fertility preservation in cancer patients, report on emerging techniques, and highlight the importance of time sensitivity and recording of outcomes.
    Current opinion in oncology. 07/2014;
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    ABSTRACT: BACKGROUND. Patients with mutations that inactivate kisspeptin signaling are infertile. Kisspeptin-54, the major circulating isoform of kisspeptin in humans, potently stimulates reproductive hormone secretion in humans. Animal studies suggest that kisspeptin is involved in generation of the luteinizing hormone surge, which is required for ovulation; therefore, we hypothesized that kisspeptin-54 could be used to trigger egg maturation in women undergoing in vitro fertilization therapy. METHODS. Following superovulation with recombinant follicle-stimulating hormone and administration of gonadotropin-releasing hormone antagonist to prevent premature ovulation, 53 women were administered a single subcutaneous injection of kisspeptin-54 (1.6 nmol/kg, n = 2; 3.2 nmol/kg, n = 3; 6.4 nmol/kg, n = 24; 12.8 nmol/kg, n = 24) to induce a luteinizing hormone surge and egg maturation. Eggs were retrieved transvaginally 36 hours after kisspeptin injection, assessed for maturation (primary outcome), and fertilized by intracytoplasmic sperm injection with subsequent transfer of one or two embryos. RESULTS. Egg maturation was observed in response to each tested dose of kisspeptin-54, and the mean number of mature eggs per patient generally increased in a dose-dependent manner. Fertilization of eggs and transfer of embryos to the uterus occurred in 92% (49/53) of kisspeptin-54-treated patients. Biochemical and clinical pregnancy rates were 40% (21/53) and 23% (12/53), respectively. CONCLUSION. This study demonstrates that a single injection of kisspeptin-54 can induce egg maturation in women with subfertility undergoing in vitro fertilization therapy. Subsequent fertilization of eggs matured following kisspeptin-54 administration and transfer of resulting embryos can lead to successful human pregnancy. TRIAL REGISTRATION. ClinicalTrials.gov NCT01667406 FUNDING. Medical Research Council, Wellcome Trust, and National Institute for Health Research.
    The Journal of clinical investigation. 07/2014;
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    ABSTRACT: Background Although in-vitro fertilisation (IVF) treatment allows infertile couples to conceive, it can result in a potentially life-threatening condition termed the ovarian hyperstimulation syndrome (OHSS). The major cause of OHSS is use of human chorionic gonadotropin (hCG) in current IVF protocols for initiating oocyte maturation. The development of a more physiological stimulus for oocyte maturation would avoid this dangerous side-effect and thus improve safety of IVF treatment. Kisspeptin is a recently identified hypothalamic hormone that acutely and potently increases endogenous secretion of luteinising hormone in a gonadotropin-releasing hormone (GnRH)-dependent manner. We aimed to investigate whether kisspeptin can induce oocyte maturation in IVF treatment. Methods In this single-centre prospective clinical trial at Hammersmith Hospital, London, women were recruited with the following inclusion criteria: age 18–35 years, body mass index less than 30 kg/m2, serum anti-Mullerian hormone 10–40 pmol/L, and no more than one previous IVF cycle. They underwent a recombinant follicle stimulating hormone plus GnRH antagonist IVF protocol with a single subcutaneous injection of kisspeptin. A control group was not recruited for ethical reasons. Primary outcome was production of mature oocytes (metaphase II oocytes) after egg collection. Participants and doctors giving IVF treatment were masked to the dose of kisspeptin administered. Women were independently randomised by the study statistician, initially to the lowest tier of kisspeptin doses (1·6 or 3·2 nmol/kg, n=2–3 per dose) and then as per protocol to a higher tier of doses (6·4 or 12·8 nmol/kg, n=21 per dose). Oocyte retrieval was done 36 h after kisspeptin injection. After intracytoplasmic sperm injection (ICSI) one or two embryos were transferred to the woman and pregnancy testing done 12 days later. Clinical pregnancy was confirmed on ultrasound scan at 6 weeks of gestation. Multiple means were compared by use of one-way ANOVA with post-hoc Bonferroni correction. Proportions were compared by χ2 test. All data were analysed on an intention-to-treat basis. Women gave written informed consent. The study received approval from the Hammersmith and Queen Charlottes Research Ethics Committee (application number 10/H0707/2) and the Medicines and Healthcare Products Regulatory Agency. The trial is registered with ClinicalTrials.gov, number NCT01667406. Findings Up to Sept 1, 2013, 47 women completed the study protocol. All doses of kisspeptin resulted in a mean 9·0-fold (SD 7·5) increase in luteinising hormone release 12 h after injection. Oocyte maturation was observed at all doses of kisspeptin. 45 women (96%) had oocyte maturation (mean number of metaphase II oocytes 7·9, SD 4·1). Embryogenesis occurred in 43 women (91%) after treatment with kisspeptin (mean number of zygotes 5·7, SD 3·5). Complete pregnancy data are awaited, but up to Sept 1, 2013, 16 (36%) of 44 women had a positive pregnancy test at 12 days post embryo transfer and ten (23%) had clinical pregnancy confirmed on ultrasound examination at 6 weeks of gestation. Clinical follow-up during pregnancy is continuing, but already the first participant to have received kisspeptin to induce oocyte maturation gave birth to a healthy baby boy in May, 2013. No adverse events were noted at any time during the study. Interpretation The results of this study suggest, for the first time, to our knowledge, that kisspeptin induces oocyte maturation in women undergoing IVF treatment. Kisspeptin might therefore offer a novel therapeutic option for fertility treatment. This small pilot study provides proof of concept that kisspeptin can stimulate oocyte maturation in women undergoing IVF treatment. Further work is now underway in a larger number of patients to determine the optimum protocol for kisspeptin administration to induce oocyte maturation in a population at high risk of OHSS. Funding UK Medical Research Council, National Institute for Health Research.
    The Lancet 02/2014; 383:S17. · 39.21 Impact Factor
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    ABSTRACT: PURPOSE: Partial molar pregnancies are rare conceptions characterized by having 69 rather than 46 chromosomes, the additional chromosome complement usually occurring as a result of fertilization of the ovum by two sperm. Although assisted conception with intracytoplasmic sperm injection (ICSI) should prevent the development of a partial molar pregnancy, occasional cases have been described after assisted conception using ICSI. The objective of this study was to investigate the cause of partial molar pregnancy in a couple who had undertaken assisted conception with ICSI. METHODS: Fluorescent microsatellite genotyping of DNA from the couple and tissue from their partial molar pregnancy was performed in order to confirm diagnosis and investigate the origin of the additional chromosome set. RESULTS: Genotyping confirmed that the partial molar tissue was triploid with an additional chromosome complement from the father. Genotyping of additional loci proximal to the centromere demonstrated that the two paternal sets of chromosomes originated in a single sperm with a double complement of paternal DNA resulting from non-reduction at the second meiotic division. CONCLUSIONS: This study confirms that partial molar pregnancy may occur after assisted conception with ICSI and that this occurs as a result of fertilization with a diploid sperm.
    Journal of Assisted Reproduction and Genetics 05/2013; · 1.82 Impact Factor
  • The Lancet 12/2011; 378(9807):1974. · 39.21 Impact Factor