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Dive into the research topics where Jovana P. Lekovich is active.

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Featured researches published by Jovana P. Lekovich.


Gynecological Endocrinology | 2016

Comparison of ovarian stimulation response in patients with breast cancer undergoing ovarian stimulation with letrozole and gonadotropins to patients undergoing ovarian stimulation with gonadotropins alone for elective cryopreservation of oocytes

Nigel Pereira; K. Hancock; Christina N. Cordeiro; Jovana P. Lekovich; Glenn L. Schattman; Z. Rosenwaks

Abstract The primary objective of this study is to compare the oocyte yield in breast cancer patients undergoing controlled ovarian stimulation (COS) using letrozole and gonadotropins with patients undergoing COS with standard gonadotropins for elective cryopreservation of oocytes. Odds ratios (OR) for the number of mature oocytes were estimated. Pregnancy outcomes for breast cancer patients undergoing frozen-thawed 2-PN embryo transfers (FETs) after oncologic treatment were also noted. 220 and 451 cycles were identified in the breast cancer and the elective cryopreservation groups, respectively. Patients in the former group had lower peak estradiol levels [464.5 (315.5–673.8) pg/mL] compared to the latter [1696 (1058–2393) pg/mL; p < 0.01]. More oocytes were retrieved in the breast cancer group (12.3 ± 3.99) compared to the elective cryopreservation group (10.9 ± 3.86; p < 0.01). The odds for mature oocytes with letrozole and gonadotropins was 2.71 (95% CI 1.29–5.72; p = 0.01). Fifty-six FETs occurred in the breast cancer group. The clinical pregnancy and live birth rates per FET cycle were 39.7%, and 32.3%, respectively. Our findings suggest that COS with letrozole and gonadotropins yield more mature oocytes at lower estradiol levels compared to COS with gonadotropins alone. Breast cancer patients undergoing FET after oncologic treatment have live birth rates comparable to age-matched counterparts.


Frontiers in Molecular Neuroscience | 2017

Fragile X-Associated Diminished Ovarian Reserve and Primary Ovarian Insufficiency from Molecular Mechanisms to Clinical Manifestations

L. Man; Jovana P. Lekovich; Z. Rosenwaks; Jeannine Gerhardt

Fragile X syndrome (FXS), is caused by a loss-of-function mutation in the FMR1 gene located on the X-chromosome, which leads to the most common cause of inherited intellectual disability in males and the leading single-gene defect associated with autism. A full mutation (FM) is represented by more than 200 CGG repeats within the FMR1 gene, resulting in FXS. A FM is inherited from women carrying a FM or a premutation (PM; 55–200 CGG repeats) allele. PM is associated with phenotypes distinct from those associated with FM. Some manifestations of the PM are unique; fragile-X-associated tremor/ataxia syndrome (FXTAS), and fragile-X-associated primary ovarian insufficiency (FXPOI), while others tend to be non-specific such as intellectual disability. In addition, women carrying a PM may suffer from subfertility or infertility. There is a need to elucidate whether the impairment of ovarian function found in PM carriers arises during the primordial germ cell (PGC) development stage, or due to a rapidly diminishing oocyte pool throughout life or even both. Due to the possibility of expansion into a FM in the next generation, and other ramifications, carrying a PM can have an enormous impact on one’s life; therefore, preconception counseling for couples carrying the PM is of paramount importance. In this review, we will elaborate on the clinical manifestations in female PM carriers and propose the definition of fragile-X-associated diminished ovarian reserve (FXDOR), then we will review recent scientific findings regarding possible mechanisms leading to FXDOR and FXPOI. Lastly, we will discuss counseling, preventative measures and interventions available for women carrying a PM regarding different aspects of their reproductive life, fertility treatment, pregnancy, prenatal testing, contraception and fertility preservation options.


Reproductive Biomedicine Online | 2016

Adjuvant gonadotrophin-releasing hormone agonist trigger with human chorionic gonadotrophin to enhance ooplasmic maturity

Nigel Pereira; Rony T. Elias; Q.V. Neri; Rachel S. Gerber; Jovana P. Lekovich; G.D. Palermo; Z. Rosenwaks

This study investigates whether an adjuvant gonadotrophin-releasing hormone agonist (GnRHa) trigger with human chorionic gonadotrophin (HCG) improves fresh intracytoplasmic sperm injection (ICSI) cycle outcomes in patients with poor fertilization history after standard HCG trigger alone. This study compared 156 patients with <40% fertilization rate in a prior ICSI cycle with standard HCG trigger who underwent another ICSI cycle with a combined 2 mg GnRHa and 1500 IU HCG ovulatory trigger. There was no difference in the baseline demographics, ovarian stimulation outcomes or sperm parameters of the groups. More mature oocytes were retrieved in the combined trigger group compared with the HCG trigger group: 12 (9-14) versus 10 (7-12); P = 0.01. The fertilization rate in the combined trigger group (59.2%) was higher than the HCG group (35.3%); P = 0.01. The odds of clinical pregnancy and live birth were 1.8 and 1.7 times higher, respectively, when comparing the former group to the latter; P = 0.03. The results suggest that combined GnRHa and HCG trigger in ICSI cycles is a reasonable approach to increase oocyte maturity, specifically ooplasmic maturity, thereby increasing fertilization and improving ICSI cycle outcomes in patients with a history of poor fertilization after standard HCG trigger alone.


Surgery Research and Practice | 2015

Surgical Management of Endometrial Polyps in Infertile Women: A Comprehensive Review

Nigel Pereira; A.C. Petrini; Jovana P. Lekovich; Rony T. Elias; S.D. Spandorfer

Endometrial polyps are benign localized lesions of the endometrium, which are commonly seen in women of reproductive age. Observational studies have suggested a detrimental effect of endometrial polyps on fertility. The natural course of endometrial polyps remains unclear. Expectant management of small and asymptomatic polyps is reasonable in many cases. However, surgical resection of endometrial polyps is recommended in infertile patients prior to treatment in order to increase natural conception or assisted reproductive pregnancy rates. There is mixed evidence regarding the resection of newly diagnosed endometrial polyps during ovarian stimulation to improve the outcomes of fresh in vitro fertilization cycles. Hysteroscopy polypectomy remains the gold standard for surgical treatment. Evidence regarding the cost and efficacy of different methods for hysteroscopic resection of endometrial polyps in the office and outpatient surgical settings has begun to emerge.


Journal of Minimally Invasive Gynecology | 2015

Effect of Methotrexate or Salpingectomy for Ectopic Pregnancy on Subsequent In Vitro Fertilization-Embryo Transfer Outcomes.

Nigel Pereira; Deanna Gerber; Rachel S. Gerber; Jovana P. Lekovich; Rony T. Elias; S.D. Spandorfer; Z. Rosenwaks

OBJECTIVE To investigate the effect of methotrexate (MTX) or salpingectomy for ectopic pregnancy on the outcomes of subsequent in vitro fertilization (IVF)-embryo transfer (ET) cycles. DESIGN Retrospective cohort study (Canadian Task Force Classification II-3). SETTING Academic center. PATIENTS All patients undergoing fresh IVF-ET between January 2004 and July 2013 after treatment of an ectopic pregnancy with MTX or salpingectomy in the preceding IVF-ET cycle were analyzed for potential inclusion. INTERVENTION MTX or laparoscopic salpingectomy for an ectopic pregnancy followed by a subsequent IVF-ET cycle. MEASUREMENTS AND MAIN RESULTS A total of 144 patients with sonographically confirmed ectopic pregnancies were identified during the study period. Of these, 107 (74.3%) patients were treated with MTX and 37 (25.7%) were treated with laparoscopic salpingectomy. Eighty-eight patients (82.2%) in the MTX group and 22 patients (59.4%) patients in the salpingectomy group underwent a subsequent IVF-ET cycle. There were no significant differences in demographic data or baseline cycle characteristics between the 2 groups. No difference was observed in basal follicle-stimulating hormone (FSH) level before and after MTX or salpingectomy treatment. Indicators of ovarian responsiveness, including total days of stimulation, total dosage of gonadotropins, and number of mature oocytes before and after either treatment, were comparable in the 2 groups. The number of doses of MTX (1 vs > 1) did not correlate with changes in ovarian response. The pregnancy outcomes, specifically live birth, were equivalent in the 2 groups. Comparing post-MTX cycles and post-salpingectomy cycles, patients in the latter group required higher doses of gonadotropins (+705 IU vs +221.5 IU; p < .01), although the number of mature oocytes remained similar in the 2 groups. CONCLUSION Treatment of ectopic pregnancies with MTX or salpingectomy might not adversely affect ovarian reserve, ovarian responsiveness, or subsequent IVF cycle outcomes. However, in our study cohort, patients treated with MTX, those s treated with laparoscopic salpingectomy required higher gonadotropin doses in a subsequent cycle to attain the same number of mature oocytes.


International Journal of Gynecology & Obstetrics | 2016

Comparison of perinatal outcomes following fresh and frozen‐thawed blastocyst transfer

Nigel Pereira; A.C. Petrini; Jovana P. Lekovich; Glenn L. Schattman; Z. Rosenwaks

To investigate the effect of ovarian stimulation on endometrial receptivity by comparing singleton pregnancy and perinatal outcomes following fresh or frozen‐thawed blastocyst transfers.


Journal of pathogens | 2015

Human Papillomavirus Infection, Infertility, and Assisted Reproductive Outcomes

Nigel Pereira; Katherine M. Kucharczyk; Jaclyn L. Estes; Rachel S. Gerber; Jovana P. Lekovich; Rony T. Elias; S.D. Spandorfer

The human papillomavirus (HPV) is a sexually transmitted infection common among men and women across all geographic and socioeconomic subgroups worldwide. Recent evidence suggests that HPV infection may affect fertility and alter the efficacy of assisted reproductive technologies. In men, HPV infection can affect sperm parameters, specifically motility. HPV-infected sperm can transmit viral DNA to oocytes, which may be expressed in the developing blastocyst. HPV can increase trophoblastic apoptosis and reduce the endometrial implantation of trophoblastic cells, thus increasing the theoretical risk of miscarriage. Vertical transmission of HPV during pregnancy may be involved in the pathophysiology of preterm rupture of membranes and spontaneous preterm birth. In patients undergoing intrauterine insemination for idiopathic infertility, HPV infection confers a lower pregnancy rate. In contrast, the evidence regarding any detrimental impact of HPV infection on IVF outcomes is inconclusive. It has been suggested that vaccination could potentially counter HPV-related sperm impairment, trophoblastic apoptosis, and spontaneous miscarriages; however, these conclusions are based on in vitro studies rather than large-scale epidemiological studies. Improvement in the understanding of HPV sperm infection mechanisms and HPV transmission into the oocyte and developing blastocyst may help explain idiopathic causes of infertility and miscarriage.


Reproductive Biomedicine Online | 2016

The role of in-vivo and in-vitro maturation time on ooplasmic dysmaturity

Nigel Pereira; Q.V. Neri; Jovana P. Lekovich; G.D. Palermo; Z. Rosenwaks

This study investigates whether the timing of in-vivo and in-vitro maturation influences ooplasmic dysmaturity. This is a retrospective comparison of intracytoplasmic sperm injection (ICSI) cycles (index cycles) complicated by complete fertilization failure (CFF) to cycles with successful fertilization in the same patient. The cycle following the index cycle was modified intentionally to increase fertilization. The times between human chorionic gonadotrophin (HCG) trigger and oocyte retrieval, HCG trigger and removal of cumulus cells, and HCG trigger and sperm injection were recorded. Fifteen patients were included. Compared with successful fertilization cycles, index (CFF) cycles showed a shorter time interval between HCG trigger and oocyte retrieval (2029.0 ± 16 versus 2195.0 ± 10 min; P < 0.001), HCG trigger and removal of cumulus cells (2201.4 ± 15 versus 2309.0 ± 23 min; P < 0.001) and oocyte retrieval and removal of cumulus cells (114.0 ± 13 versus 171.8 ± 15 min; P < 0.001). The interval between HCG trigger and ICSI was comparable between groups. Findings reveal novel patterns in time intervals between HCG trigger, oocyte retrieval, removal of cumulus cells and ICSI. Thus, modulating time intervals between HCG trigger, oocyte retrieval, removal of cumulus cells and ICSI to grant fertilization seems feasible.


Fertility and Sterility | 2016

Does the time interval between hysteroscopic polypectomy and start of in vitro fertilization affect outcomes

Nigel Pereira; Selma Amrane; Jaclyn L. Estes; Jovana P. Lekovich; Rony T. Elias; P. Chung; Z. Rosenwaks

OBJECTIVE To investigate whether the time interval between hysteroscopic polypectomy and the start of IVF-ET cycles affect IVF cycle outcomes. DESIGN Retrospective cohort. SETTING Academic center. PATIENT(S) All patients diagnosed with endometrial polyps undergoing hysteroscopic polypectomy before fresh IVF-ET. INTERVENTION(S) Hysteroscopic polypectomy. MAIN OUTCOME MEASURE(S) Patients were divided into three groups based on the time interval between hysteroscopic polypectomy and the start of a fresh IVF-ET cycle. Group 1 consisted of patients who underwent IVF-ET after their next menses, group 2 after two or three menstrual cycles, and group 3 after more than three menstrual cycles. Demographics, baseline IVF characteristics, controlled ovarian stimulation response, and pregnancy outcomes after ET were compared among the groups. RESULT(S) A total of 487 patients met inclusion criteria: 241 in group 1 (49.5%), 172 in group 2 (35.3%), and 74 in group 3 (15.2%). There were no differences in the baseline characteristics of the three groups. Ovarian stimulation outcomes, specifically total stimulation days, total gonadotropins administered, and number of oocytes retrieved, were similar between groups. There were no differences in the mean number of embryos transferred. The overall pregnancy outcomes were similar for groups 1, 2, and 3: implantation rate (42.4%, 41.2%, and 42.1%, respectively), clinical pregnancy rate (48.5%, 48.3%, and 48.6%), spontaneous miscarriage rate (4.56%, 4.65%, and 4.05%), and live birth rate (44.0, 43.6%, and 44.6%). CONCLUSION(S) Because waiting for two or more menstrual cycles after hysteroscopic polypectomy does not necessarily yield superior outcomes, patients can undergo ovarian stimulation after their next menses without affecting IVF-ET outcomes.


Journal of pathogens | 2016

Antibiotic Prophylaxis for Gynecologic Procedures prior to and during the Utilization of Assisted Reproductive Technologies: A Systematic Review

Nigel Pereira; A.P. Hutchinson; Jovana P. Lekovich; Elie Hobeika; Rony T. Elias

The use of assisted reproductive technologies (ART) has increased steadily. There has been a corresponding increase in the number of ART-related procedures such as hysterosalpingography (HSG), saline infusion sonography (SIS), hysteroscopy, laparoscopy, oocyte retrieval, and embryo transfer (ET). While performing these procedures, the abdomen, upper vagina, and endocervix are breached, leading to the possibility of seeding pelvic structures with microorganisms. Antibiotic prophylaxis is therefore important to prevent or treat any procedure-related infections. After careful review of the published literature, it is evident that routine antibiotic prophylaxis is generally not recommended for the majority of ART-related procedures. For transcervical procedures such as HSG, SIS, hysteroscopy, ET, and chromotubation, patients at risk for pelvic infections should be screened and treated prior to the procedure. Patients with a history of pelvic inflammatory disease (PID) or dilated fallopian tubes are at high risk for postprocedural infections and should be given antibiotic prophylaxis during procedures such as HSG, SIS, or chromotubation. Antibiotic prophylaxis is recommended prior to oocyte retrieval in patients with a history of endometriosis, PID, ruptured appendicitis, or multiple prior pelvic surgeries.

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