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Dive into the research topics where Shvetha M. Zarek is active.

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Featured researches published by Shvetha M. Zarek.


Journal of Assisted Reproduction and Genetics | 2012

Leiomyoma: genetics, assisted reproduction, pregnancy and therapeutic advances

Gary Levy; M.J. Hill; S. Beall; Shvetha M. Zarek; James H. Segars; William H. Catherino

PurposeUterine leiomyomas are common, benign, reproductive tract tumors affecting a majority of reproductive aged women. They are associated with gynecologic morbidity and detrimentally affect reproductive potential. The etiology of leiomyomas is poorly understood and their diagnosis prior to treatment with Assisted Reproductive Technologies (ART) represents a management dilemma. The purpose of this paper is to review known genetic and molecular contributions to the etiologies of leiomyomas, describe their impact on ART outcomes and reproductive potential, and review alternative therapies and future directions in management.MethodsA critical review of the literature pertaining to genetic component of uterine leiomyomas, their impact on ART and pregnancy and leiomyoma therapeutics was performed.ResultsUterine leiomyomas are characterized by complex molecular mechanisms. Their location and size determines their potential detriment to ART and reproductive function and novel therapeutic modalities are being developed.ConclusionThe high prevalence of uterine leiomyomas and their potential detrimental influence on ART and reproductive function warrants continued well-designed studies to ascertain their etiology, optimal treatment and novel less morbid therapies.


Seminars in Reproductive Medicine | 2014

Potential Influence of the Microbiome on Infertility and Assisted Reproductive Technology

Ido Sirota; Shvetha M. Zarek; James H. Segars

Although an altered vaginal microbiota has been demonstrated to affect parturition, its role in assisted reproductive technologies is uncertain. Nevertheless, the effect of known pathogens such as Mycoplasma tuberculosis, Chlamydia trachomatis, and Neisseria gonorrhoeae is clear, causing subclinical changes thought to be risk factors in subfertility. The Human Microbiome Project (HMP) has allowed for metagenomic studies to aid in characterizing normal vaginal flora. Recent findings from the HMP demonstrate that many different species of Lactobacillus are present in the vaginal tract, with a few that predominate. Studies that characterize the vaginal microbiome in assisted reproductive technology support the hypothesis that colonizing the transfer-catheter tip with Lactobacillus crispatus at the time of embryo transfer may increase the rates of implantation and live birth rate while decreasing the rate of infection. In addition, there is some evidence that a progesterone-resistant endometrium might increase the risk of an abnormal vaginal microbiome.


The Journal of Clinical Endocrinology and Metabolism | 2016

Subclinical Hypothyroidism and Thyroid Autoimmunity Are Not Associated With Fecundity, Pregnancy Loss, or Live Birth

Torie C. Plowden; Enrique F. Schisterman; Lindsey A. Sjaarda; Shvetha M. Zarek; Neil J. Perkins; Robert Silver; Noya Galai; Alan H. DeCherney; Sunni L. Mumford

CONTEXT Prior studies examining associations between subclinical hypothyroidism and antithyroid antibodies with early pregnancy loss and live birth suggest mixed results and time to pregnancy (TTP) has not been studied in this patient population. OBJECTIVE This study sought to examine associations of prepregnancy TSH concentrations and thyroid autoimmunity with TTP, pregnancy loss, and live birth among women with proven fecundity and a history of pregnancy loss. DESIGN AND SETTING This was a prospective cohort study from a large, randomized controlled trial that took place at four medical centers in the United States. PATIENTS OR OTHER PARTICIPANTS Healthy women, ages 18-40 y, who were actively attempting to conceive and had one or two prior pregnancy losses and no history of infertility were eligible for the study. INTERVENTION There were no interventions. MAIN OUTCOME MEASURE TTP, pregnancy loss, and live birth. RESULTS Women with TSH ≥ 2.5 mIU/L did not have an increased risk of pregnancy loss (risk ratio, 1.07; 95% confidence interval [CI], 0.81-1.41) or a decrease in live birth rate (risk ratio, 0.97; 95% CI, 0.88-1.07) or TTP (fecundability odds ratio, 1.09; 95% CI, 0.90-1.31) compared with women with TSH <2.5 mIU/L after adjustment for age and body mass index. Similar findings were observed for women with thyroid autoimmunity and after additional adjustment for treatment assignment. CONCLUSIONS Among healthy fecund women with a history pregnancy loss, TSH levels ≥ 2.5 mIU/L or the presence of antithyroid antibodies were not associated with fecundity, pregnancy loss, or live birth. Thus, women with subclinical hypothyroidism or thyroid autoimmunity can be reassured that their chances of conceiving and achieving a live birth are likely unaffected by marginal thyroid dysfunction.


The Journal of Clinical Endocrinology and Metabolism | 2015

Is anti-müllerian hormone associated with fecundability? Findings from the EAGeR trial

Shvetha M. Zarek; Emily M. Mitchell; Lindsey A. Sjaarda; Sunni L. Mumford; Robert M. Silver; Joseph B. Stanford; Noya Galai; Mark White; Karen C. Schliep; Alan H. DeCherney; Enrique F. Schisterman

OBJECTIVE The objective of the study was to evaluate whether anti-Müllerian hormone (AMH) is associated with fecundability among women with proven fecundity and a history of pregnancy loss. DESIGN This was a prospective cohort study within a multicenter, block-randomized, double-blind, placebo-controlled clinical trial ( clinicaltrials.gov , number NCT00467363). SETTING The study was conducted at four US medical centers (2006-2012). PARTICIPANTS Participating women were aged 18-40 years, with a history of one to two pregnancy losses who were actively attempting pregnancy. MAIN OUTCOME MEASURES Time to human chorionic gonadotropin detected and clinical pregnancy were assessed using Cox proportional hazard regression models to estimate fecundability odds ratios (fecundability odds ratios with 95% confidence interval [CI]) adjusted for age, race, body mass index, income, low-dose aspirin treatment, parity, number of previous losses, and time since most recent loss. Analyses examined by preconception AMH levels: low (<1.00 ng/mL, n = 124); normal (referent 1.00-3.5 ng/mL, n = 595); and high (>3.5 ng/mL, n = 483). RESULTS Of the 1202 women with baseline AMH levels, 82 women with low AMH (66.1%) achieved an human chorionic gonadotropin detected pregnancy, compared with 383 with normal AMH (65.2%) and 315 with high AMH level (65.2%). Low or high AMH levels relative to normal AMH (referent) were not associated with fecundability (low AMH: fecundability odds ratios 1.13, 95% CI 0.85-1.49; high AMH: FOR 1.04, 95% CI 0.87-1.24). CONCLUSIONS Lower and higher AMH values were not associated with fecundability in unassisted conceptions in a cohort of fecund women with a history of one or two prior losses. Our data do not support routine AMH testing for preconception counseling in young, fecund women.


Fertility and Sterility | 2014

Assessment of anovulation in eumenorrheic women: comparison of ovulation detection algorithms

Kristine E. Lynch; Sunni L. Mumford; Karen C. Schliep; Brian W. Whitcomb; Shvetha M. Zarek; Anna Z. Pollack; Elizabeth R. Bertone-Johnson; Michelle Danaher; Jean Wactawski-Wende; Audrey J. Gaskins; Enrique F. Schisterman

OBJECTIVE To compare previously used algorithms to identify anovulatory menstrual cycles in women self-reporting regular menses. DESIGN Prospective cohort study. SETTING Western New York. PATIENT(S) Two hundred fifty-nine healthy, regularly menstruating women followed for one (n=9) or two (n=250) menstrual cycles (2005-2007). INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Prevalence of sporadic anovulatory cycles identified using 11 previously defined algorithms that use E2, P, and LH concentrations. RESULT(S) Algorithms based on serum LH, E2, and P levels detected a prevalence of anovulation across the study period of 5.5%-12.8% (concordant classification for 91.7%-97.4% of cycles). The prevalence of anovulatory cycles varied from 3.4% to 18.6% using algorithms based on urinary LH alone or with the primary E2 metabolite, estrone-3-glucuronide, levels. CONCLUSION(S) The prevalence of anovulatory cycles among healthy women varied by algorithm. Mid-cycle LH surge urine-based algorithms used in over-the-counter fertility monitors tended to classify a higher proportion of anovulatory cycles compared with luteal-phase P serum-based algorithms. Our study demonstrates that algorithms based on the LH surge, or in conjunction with estrone-3-glucuronide, potentially estimate a higher percentage of anovulatory episodes. Addition of measurements of postovulatory serum P or urine pregnanediol may aid in detecting ovulation.


Fertility and Sterility | 2015

Gynecologic health and disease in relation to the microbiome of the female reproductive tract

K.A. Green; Shvetha M. Zarek; William H. Catherino

It is well established that the vagina is colonized by bacteria that serve important roles in homeostasis. Imbalances in the proportion of bacteria may lead to a predisposition to infection or reproductive complications. Molecular-based approaches demonstrated a greater degree of microbial diversity both within and between women than previously recognized. The vaginal microbiome may fluctuate during various states of health, such as during the menstrual cycle or after menopause, and there may be differences in the vaginal microbiome between women of different ethnicities. Furthermore, the specific composition of the vaginal microbiome may influence the predisposition to dysbiosis and the transmission of sexually transmitted infections. An understanding of the diversity of the vaginal microbial environment during states of health is essential for the identification of risk factors for disease and the development of appropriate treatment.


The American Journal of Clinical Nutrition | 2016

Dietary fat intake and reproductive hormone concentrations and ovulation in regularly menstruating women

Sunni L. Mumford; Jorge E. Chavarro; Cuilin Zhang; Neil J. Perkins; Lindsey A. Sjaarda; Anna Z. Pollack; Karen C. Schliep; Kara A. Michels; Shvetha M. Zarek; Torie C. Plowden; Rose G. Radin; Lynne C. Messer; Robyn A Frankel; Jean Wactawski-Wende

BACKGROUND Emerging evidence suggests potential links between some dietary fatty acids and improved fertility, because specific fatty acids may affect prostaglandin synthesis and steroidogenesis. OBJECTIVE The objective of this exploratory study was to evaluate associations between total and specific types of dietary fat intake and 1) hormone concentrations and 2) the risk of sporadic anovulation in a cohort of 259 regularly menstruating women in the BioCycle Study. DESIGN Endogenous reproductive hormones were measured up to 8 times/cycle for up to 2 cycles, with visits scheduled with the use of fertility monitors. Dietary intake was assessed with up to four 24-h recalls/cycle. Linear mixed models and generalized linear models were used to evaluate the associations between dietary fatty acids and both reproductive hormone concentrations and ovulatory status. All models were adjusted for total energy intake, age, body mass index, and race. RESULTS Relative to the lowest levels of percentage of energy from total fat, the highest tertile was associated with increased total and free testosterone concentrations (total: percentage change of 4.0%; 95% CI: 0.7%, 7.3%; free: percentage change of 4.1%; 95% CI: 0.5%, 7.7%). In particular, the percentage of energy from polyunsaturated fatty acids (PUFAs) in the highest tertile was associated with increases in total and free testosterone (total: percentage change of 3.7%; 95% CI: 0.6%, 6.8%; free: percentage change of 4.0%; 95% CI: 0.5%, 7.5%). The PUFA docosapentaenoic acid (22:5n-3) was not significantly associated with testosterone concentrations (P-trend = 0.86 in energy substitution models) but was associated with increased progesterone and a reduced risk of anovulation (highest tertile compared with the lowest tertile: RR: 0.42; 95% CI: 0.18, 0.95). Fat intakes were not associated with other reproductive hormone concentrations. CONCLUSIONS These results indicate that total fat intake, and PUFA intake in particular, is associated with very small increases in testosterone concentrations in healthy women and that increased docosapentaenoic acid was associated with a lower risk of anovulation.


The American Journal of Clinical Nutrition | 2015

Alcohol intake, reproductive hormones, and menstrual cycle function: a prospective cohort study.

Karen C. Schliep; Shvetha M. Zarek; Enrique F. Schisterman; Jean Wactawski-Wende; Maurizio Trevisan; Lindsey A. Sjaarda; Neil J. Perkins; Sunni L. Mumford

BACKGROUND Although habitual low-to-moderate alcohol intake has been linked with reduced all-cause mortality and morbidity, the effect of recent alcohol intake on female reproductive function has not been clearly established. OBJECTIVE We assessed the relation between acute alcohol consumption, reproductive hormones, and markers of menstrual cycle dysfunction including sporadic anovulation, irregular cycle length, luteal phase deficiency, long menses, and heavy blood loss. DESIGN A total of 259 healthy, premenopausal women from Western New York were followed for ≤2 menstrual cycles (2005-2007) and provided fasting blood specimens during ≤8 visits/cycle and four 24-h dietary recalls/cycle. Linear mixed models were used to estimate associations between previous days alcohol intake and hormone concentrations, whereas Poisson regression was used to assess RR of cycle-average alcohol intake and menstrual cycle function. RESULTS For every alcoholic drink consumed, the geometric mean total and free estradiol, total and free testosterone, and luteinizing hormone were higher by 5.26% (95% CI: 1.27%, 9.41%), 5.82% (95% CI: 1.81%, 9.99%), 1.56% (95% CI: 0.23%, 2.90%), 1.42% (95% CI: 0.02%, 2.84%), and 6.18% (95% CI: 2.02%, 10.52%), respectively, after adjustment for age, race, percentage of body fat, perceived stress, pain-medication use, sexual activity, caffeine, and sleep. Binge compared with nonbinge drinking (defined as reporting ≥4 compared with <4 drinks/d, respectively) was associated with 64.35% (95% CI: 18.09%, 128.71%) and 63.53% (95% CI: 17.41%, 127.73%) higher total and free estradiol. No statistically significant associations were shown between cycle-average alcohol intake and menstrual cycle function. CONCLUSION Although recent moderate alcohol intake does not appear to have adverse short-term effects on menstrual cycle function, including sporadic anovulation, potential protective and deleterious long-term effects of alterations in reproductive hormones on other chronic diseases warrant additional investigation.


Journal of Assisted Reproduction and Genetics | 2015

Vitamin D and assisted reproduction: should vitamin D be routinely screened and repleted prior to ART? A systematic review

Michelle M. Pacis; Chelsea N. Fortin; Shvetha M. Zarek; Sunni L. Mumford; James H. Segars

PurposeTo review the current literature regarding the role of vitamin D status in pregnancy outcomes in women undergoing assisted reproductive technology (ART) and to assess cost-effectiveness of routine vitamin D deficiency screening and repletion prior to initiation of ART.MethodsA systematic literature review was conducted using PubMed. Relevant study outcomes were compared among the selected studies. A cost-benefit analysis was performed using a decision tree mathematical model with sensitivity analyses from the perspective of direct societal cost. Published data were used to estimate probabilities and costs in 2014 US dollars.ResultsThirty-four articles were retrieved, of which eight met inclusion criteria. One study demonstrated a negative relationship between vitamin D status and ART outcomes, while two studies showed no association. The remaining five studies concluded that ART outcomes improved after vitamin D repletion.ConclusionThe majority of reviewed studies reported a decrement in ART outcomes in patients with vitamin D deficiency. Cost-benefit analyses suggested that screening and supplementing vitamin D prior to ART might be cost effective, but further evidence is needed. Given the absence of Level I evidence regarding vitamin D status and ART outcomes, full endorsement of routine vitamin D screening and supplementation prior to ART is premature.


Obstetrics & Gynecology | 2016

Complications and safety of preconception low-dose aspirin among women with prior pregnancy losses

Katherine A. Ahrens; Robert Silver; Sunni L. Mumford; Lindsey A. Sjaarda; Neil J. Perkins; Jean Wactawski-Wende; Noya Galai; Janet Townsend; Anne Lynch; Laurie Lesher; David Faraggi; Shvetha M. Zarek; Enrique F. Schisterman

OBJECTIVE: To evaluate complications and safety of preconception low-dose aspirin in 1,228 U.S. women (2007–2011). METHODS: Evaluation of the safety of low-dose aspirin in the participants and their fetuses was a planned secondary analysis of the Effects of Aspirin in Gestation and Reproduction trial, a multicenter, block-randomized, double-blind, placebo-controlled trial investigating the effect of low-dose aspirin on the incidence of live birth. Women aged 18–40 years with a history of one to two pregnancy losses trying to conceive were randomized to daily low-dose aspirin (81 mg, n=615) or placebo (n=613) and were followed for up to six menstrual cycles or through gestation if they became pregnant. Emergency care visits and possible aspirin-related symptoms were assessed at each study follow-up using standardized safety interviews. In addition, complications for both the participant and her fetus or neonate were captured prospectively using case report forms, interviews conducted during pregnancy and postpartum, and medical records. RESULTS: The proportion of women with at least one possible aspirin-related symptom during the trial was similar between treatment arms (456 [74%] low-dose aspirin compared with 447 [73%] placebo, P=.65) as was the proportion with at least one emergency care visit (104 [17%] low-dose aspirin compared with 99 [16%] placebo, P=.76). Maternal complications were evenly distributed by treatment arm with the exception of vaginal bleeding, which was more commonly reported in the low-dose aspirin arm (22% compared with 17%, P=.02). The distribution of fetal and neonatal complications—which included three stillbirths, three neonatal deaths, and 10 neonates with birth defect(s)—was similar between treatment arms. CONCLUSION: Although rare but serious complications resulting from low-dose aspirin cannot be ruled out, preconception low-dose aspirin appears to be well tolerated by women trying to conceive, women who become pregnant, and by their fetuses and neonates.

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Sunni L. Mumford

National Institutes of Health

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Lindsey A. Sjaarda

National Institutes of Health

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Alan H. DeCherney

National Institutes of Health

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Neil J. Perkins

National Institutes of Health

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Torie C. Plowden

National Institutes of Health

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