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Featured researches published by R. Mejia.


Journal of Minimally Invasive Gynecology | 2014

Effect of surgery for endometrioma on ovarian function.

Divya K. Shah; R. Mejia; Dan I. Lebovic

Endometriosis affects a significant proportion of reproductive-aged women. The impact of the disease on ovarian function is an important consideration when planning treatment in women who want to retain the potential of future childbearing. This review will specifically address the association between endometriomas and diminished ovarian reserve, with a particular focus on the impact of surgical endometrioma resection on ovarian function. The existing literature supports an adverse effect of ovarian endometriomas on spontaneous ovulation rates, markers of ovarian reserve, and response to ovarian stimulation, although data on clinical pregnancy and live birth rates remain inconsistent. Surgical removal of endometriomas may worsen ovarian function by removing healthy ovarian cortex or compromising blood flow to the ovary. It is evident that surgical excision of endometriomas acutely impairs ovarian function as measured by ovarian reserve markers; whether this represents progressive or long term impairment remains the subject of ongoing investigation.


Molecular Endocrinology | 2015

Activation of Gq/11 in the Mouse Corpus Luteum Is Required for Parturition

R. Mejia; Courtney Waite; Mario Ascoli

Mice with a deletion of Gα(q/11) in granulosa cells were previously shown to be subfertile. They also have a reduced ovulatory response due to a deficiency in the ability of the activated LH receptor to fully induce the granulosa cell progesterone receptor. Because this conditional deletion of Gα(q/11) will interfere with the actions of any G protein-coupled receptor that activates G(q/11) in granulosa or luteal cells, we sought to determine whether the actions of other hormones that contribute to fertility were also impaired. We focused our attention on prostaglandin F2 (PGF2)α, because this hormone is known to activate phospholipase C (a prominent Gα(q/11) effector) in luteal cells and because the action of PGF2α on luteal cells is the first step in the murine parturition pathway. Our data show that the conditional deletion of Gα(q/11) from granulosa cells prevents the ability of PGF2α to induce Akr1c18 in luteal cells. Akr1c18 codes for 20α-hydroxysteroid dehydrogenase, an enzyme that inactivates progesterone. The PGF2α-mediated induction of this enzyme towards the end of pregnancy increases the inactivation of progesterone and precipitates parturition in mice. Thus, the conditional deletion of Gαq/11 from granulosa/luteal cells prevents the progesterone withdrawal that occurs at the end of pregnancy and impairs parturition. This novel molecular defect contributes to the subfertile phenotype of the mice with a deletion of Gα(q/11) from granulosa cells.


Biology of Reproduction | 2016

Gq/11-Dependent Changes in the Murine Ovarian Transcriptome at the End of Gestation

Courtney Waite; R. Mejia; Mario Ascoli

ABSTRACT Parturition in rodents is highly dependent on the engagement of the luteal prostaglandin F2 alpha receptor, which, through activation of the Gq/11 family of G proteins, increases the expression of Akr1c18, leading to an increase in progesterone catabolism. To further understand the involvement of Gq/11 on luteolysis and parturition, we used microarray analysis to compare the ovarian transcriptome of mice with a granulosa/luteal cell-specific deletion of Galphaq/11 with their control littermates on Day 18 of pregnancy, when mice from both genotypes are pregnant, and on Day 22, when mice with a granulosa/luteal cell-specific deletion of Galphaq/11 are still pregnant but their control littermates are 1–2 days postpartum. Ovarian genes up-regulated at the end of gestation in a Galphaq/11 -dependent fashion include genes involved in focal adhesion and extracellular matrix interactions. Genes down-regulated at the end of gestation in a Galphaq/11-dependent manner include Serpina6 (which encodes corticosteroid-binding globulin); Enpp2 (which encodes autotaxin, the enzyme responsible for the synthesis of lysophosphatidic acid); genes involved in protein processing and export; reproductive genes, such as Lhcgr; the three genes needed to convert progesterone to estradiol (Cyp17a1, Hsd17b7, and Cyp19a1); and Inha. Activation of ovarian Gq/11 by engagement of the prostaglandin F2 alpha receptor on Day 18 of pregnancy recapitulated the regulation of many but not all of these genes. Thus, although the ovarian transcriptome at the end of gestation is highly dependent on the activation of Gq/11, not all of these changes are dependent on the actions of prostaglandin F2 alpha.


American Journal of Obstetrics and Gynecology | 2015

Ethical issues identified by obstetrics and gynecology learners through a novel ethics curriculum

R. Mejia; Laura Shinkunas; Ginny L. Ryan

OBJECTIVEnObstetrics and gynecology (ob/gyn) is fraught with bioethical issues, the professional significance of which may vary based on clinical experience. Our objective was to utilize our novel ethics curriculum to identify ethics and professionalism issues highlighted by ob/gyn learners and to compare responses between learner levels to further inform curricular development.nnnSTUDY DESIGNnWe introduced an integrated and dynamic ob/gyn ethics and professionalism curriculum and mixed methods analysis of 181 resulting written reflections (case observation and assessments) from third-year medical students and from first- to fourth-year ob/gyn residents. Content was compared by learner level using basic thematic analysis and summary statistics.nnnRESULTSnWithin the 7 major ethics and professionalism domains, learners wrote most frequently about miscellaneous ob/gyn issues such as periviability and abortion (22% of students, 20% of residents) and problematic treatment decisions (20% of students, 19% of residents) rather than professional duty, communication, justice, student-/resident-specific issues, or quality of care. The most commonly discussed ob/gyn area by both learner groups was obstetrics rather than gynecology, gynecologic oncology, or reproductive endocrinology and infertility, although residents were more likely to discuss obstetrics-related concerns than students (65% vs 48%; P = .04) and students wrote about gynecologic oncology-related concerns more frequently than residents (25% vs 6%; P = .002). In their reflections, sources of ethical value (eg, the 4 classic ethics principles, professional guidelines, and consequentialism) were cited more frequently and in greater number by students than by residents (82% of students cited at least 1 source of ethical value vs 65% of residents; P = .01). Residents disagreed more frequently with the ethical propriety of clinical management than did students (67% vs 43%; P = .005).nnnCONCLUSIONnOur study introduces an innovative and dynamic approach to an ob/gyn ethics and professionalism curriculum that highlights important learner-identified ethics and professionalism issues both specific to ob/gyn and common to clinical medicine. Findings will help ob/gyn educators best utilize and refine this flexible curriculum such that it is appropriately focused on topics relevant to each learner level.


Journal of Assisted Reproduction and Genetics | 2018

Live birth and multiple birth rates in US in vitro fertilization treatment using donor oocytes: a comparison of single-embryo transfer and double-embryo transfer

V. E. Klenov; Sheree L. Boulet; R. Mejia; Dmitry M. Kissin; Erika M. Munch; Abigail C. Mancuso; B.J. Van Voorhis

ObjectiveTo compare live birth rates (LBRs) and multiple birth rates (MBRs) between elective single-embryo transfer (eSET) and double-embryo transfer (DET) in donor oocyte in vitro fertilization (IVF) treatments in both a cycle-level and clinic-level analysis.MethodsDonor oocyte IVF treatments performed by US IVF clinics reporting to the Centers for Disease Control and Prevention in 2013–2014 were included in the analysis. Primary outcomes included LBR and MBR. Secondary outcomes included gestational age at delivery (GA) and birth weight (BW) of offspring. These outcomes were evaluated on an individual cycle level as well as on the clinic level.ResultsIn multivariable models, LBR did not change significantly as clinics utilized eSET more frequently. MBR decreased significantly as utilization of eSET increased, from 39% MBR in clinics that utilized eSET 0–9% of the time to 7% MBR in clinics that used eSET 70% of the time (Pu2009<u2009.0001). Mean BW and GA of IVF-conceived offspring both increased as clinics utilized eSET more frequently (2778 to 3185xa0g [Pu2009<u2009.0001] and 37.5 to 38.5xa0weeks [Pu2009=u2009.02] for clinics with the lowest and highest eSET utilization, respectively).ConclusionsUS IVF clinics utilizing eSET with higher frequencies have clinically comparable LBRs and significantly lower MBRs than clinics with lower-frequency eSET utilization. Mean offspring BW and GA increased with higher eSET utilization, further confirming the improved safety of this practice.


Proceedings in Obstetrics and Gynecology | 2013

Ethics issues identified by obstetrics and gynecology learners

R. Mejia; Laura Shinkunas; Ginny L. Ryan

This study evaluated a specific ethics and professionalism curriculum whereby medical students and residents provided a written assessment on various ethical issues encountered during their Ob/Gyn rotations. Our goal with this study was to retrospectively evaluate the content of reflections written by medical students and resident physicians and compare content and issues identified by each learner level. Our ultimate goal is to use these data to refine and improve the ethics and professionalism curriculum for Ob/Gyn medical learners.


Fertility and Sterility | 2018

A randomized controlled trial of combination of letrozole and clomiphene citrate versus letrozole alone for ovulation induction in women with polycystic ovary syndrome

R. Mejia; K.M. Summers; J. Kresowik; B.J. Van Voorhis


Fertility and Sterility | 2018

Effect of body weight on early hormone levels in singleton pregnancies resulting in delivery following in vitro fertilization

R. Mejia; K.M. Summers; T.W. Cox; E. Nguyen; Amy E.T. Sparks; B.J. Van Voorhis


Fertility and Sterility | 2018

Pregnancy predictors in the fresh cycle using dual trigger

R.K. Chung; Abigail C. Mancuso; Amy E.T. Sparks; H.E. Duran; R. Mejia


Fertility and Sterility | 2018

Effect of endometrial thickness on live birth rate in both fresh and frozen blastocyst transfers

T. Place; R. Mejia; Amy E.T. Sparks; Hakan E. Duran; K.M. Summers; P. Ten Eyck; B.J. Van Voorhis

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K.M. Summers

Roy J. and Lucille A. Carver College of Medicine

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Courtney Waite

Roy J. and Lucille A. Carver College of Medicine

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Dmitry M. Kissin

Centers for Disease Control and Prevention

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Mario Ascoli

Roy J. and Lucille A. Carver College of Medicine

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Sheree L. Boulet

Centers for Disease Control and Prevention

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Abbey J. Hardy-Fairbanks

University of Iowa Hospitals and Clinics

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Abigail C. Mancuso

University of Iowa Hospitals and Clinics

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Colleen K. Stockdale

University of Iowa Hospitals and Clinics

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