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Dive into the research topics where Amy E.T. Sparks is active.

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Featured researches published by Amy E.T. Sparks.


Obstetrics & Gynecology | 2006

Obstetric outcomes after in vitro fertilization in obese and morbidly obese women.

Anuja Dokras; Lindsey E. Baredziak; Jill Blaine; Craig H. Syrop; Bradley J. VanVoorhis; Amy E.T. Sparks

OBJECTIVE: In addition to numerous health detriments caused by obesity, fertility and pregnancy success may also be compromised. The aims of this study were to compare the effects of obesity and morbid obesity on in vitro fertilization (IVF) outcomes. We also investigated the effects of obesity on obstetric outcomes after IVF treatment. METHODS: Retrospective study of women less than 38 years of age during their first fresh IVF cycle (January 1995 to April 2005). RESULTS: A total of 1,293 women were included in the study, with 236 obese women (body mass index [BMI] = 30–39.9) and 79 morbidly obese women (BMI ≥ 40). The morbidly obese group had a 25.3% IVF cycle cancellation rate compared with 10.9% in normal-weight women (odds ratio 2.73, 95% confidence interval 1.49–5.0), P < .001). Morbidly obese women without polycystic ovarian syndrome had an even higher cancellation rate (33%). Women with higher BMI required significantly more days of gonadotropin stimulation but had lower peak estradiol levels (P < .001). There were no significant differences in clinical pregnancy or delivery rates between the four BMI groups. Of the women who delivered, there was a significant linear trend for risk of preeclampsia, gestational diabetes, and cesarean delivery with increasing BMI (P < .03). CONCLUSION: We report a significantly higher risk for IVF cycle cancellation in morbidly obese patients with no effect of BMI on clinical pregnancy or delivery rate. However, obese and morbidly obese subjects had a significantly higher risk for obstetric complications. This target population should be aggressively counseled regarding their increased obstetric risk and offered treatment options for weight reduction before the initiation of fertility therapy. LEVEL OF EVIDENCE: II-2


Fertility and Sterility | 2001

Effect of the total motile sperm count on the efficacy and cost-effectiveness of intrauterine insemination and in vitro fertilization

Bradley J. Van Voorhis; Mitchell J. Barnett; Amy E.T. Sparks; Craig H. Syrop; Gary E. Rosenthal; Jeffrey D. Dawson

OBJECTIVE To determine prognostic factors for achieving a pregnancy with intrauterine insemination (IUI) and IVF. To compare the effectiveness and cost-effectiveness of IUI and IVF based on semen analysis results. DESIGN Retrospective cohort study. SETTING Academic university hospital-based infertility center. PATIENT(S) One thousand thirty-nine infertile couples undergoing 3,479 IUI cycles. Four hundred twenty-four infertile couples undergoing 551 IVF cycles. INTERVENTION(S) IUI and IVF treatment. MAIN OUTCOME MEASURE(S) Multiple logistic regression analysis was used to assess the significance of prognostic factors including a womans age, gravidity, duration of infertility, diagnoses, use of ovulation induction, and sperm parameters for predicting the outcomes of clinical pregnancy and live birth rate after the first cycle of IUI and IVF. The relative effectiveness and cost-effectiveness of these treatments were then determined based on sperm count results. RESULT(S) Female age, gravidity, and use of ovulation induction were all independent factors in predicting pregnancy after IUI. The average total motile sperm count in the ejaculate was also an important factor, with a threshold value of 10 million. For IVF, only female age was an important predictor for both clinical and ongoing pregnancy. When the average total motile sperm count was under 10 million, IVF with ICSI was more cost-effective than IUI in our clinic. CONCLUSION(S) An average total motile sperm count of 10 million may be a useful threshold value for decisions about treating a couple with IUI or IVF.


Environmental Health Perspectives | 2010

Are Environmental Levels of Bisphenol A Associated with Reproductive Function in Fertile Men

Jaime Mendiola; Niels Jørgensen; Anna Maria Andersson; Antonia M. Calafat; Xiaoyun Ye; J. Bruce Redmon; Erma Z. Drobnis; Christina Wang; Amy E.T. Sparks; Sally W. Thurston; Fan Liu; Shanna H. Swan

Background Rodent and in vitro studies have demonstrated the estrogenicity of bisphenol A (BPA). However, few studies have examined the relationship between human exposure to BPA and male reproductive function. Objectives We investigated the relationships between environmental BPA exposure and reproductive parameters, including semen quality and male reproductive hormones, in prospectively recruited fertile men. Methods Participants (n = 375) were partners of pregnant women who participated in the Study for Future Families in four U.S. cities, and all of the men provided blood, semen, and urine samples. BPA was measured in urine. Serum samples were analyzed for reproductive hormones, including follicle-stimulating hormone, luteinizing hormone (LH), testosterone, inhibin B, estradiol, and sex hormone–binding globulin (SHBG), as well as the free androgen index (FAI). Semen analyses were performed according to World Health Organization criteria. Pearson correlations were used for unadjusted analyses, and multiple linear regression analyses were used to examine associations controlling for age, body mass index, smoking, ethnicity, urinary creatinine concentration, time of sample collection, and duration of abstinence. Results After multivariate adjustment, we observed no significant associations between any semen parameter and urinary BPA concentration. However, a significant inverse association was found between urinary BPA concentration and FAI levels and the FAI/LH ratio, as well as a significant positive association between BPA and SHBG. Conclusions Our results suggest that, in fertile men, exposure to low environmental levels of BPA may be associated with a modest reduction in markers of free testosterone, but any effects on reproductive function are likely to be small, and of uncertain clinical significance.


Obstetrics & Gynecology | 1996

The Effects of Smoking on Ovarian Function and Fertility During Assisted Reproduction Cycles

Bradley J. Van Voorhis; Jeffrey D. Dawson; Dale W. Stovall; Amy E.T. Sparks; Craig H. Syrop

Objective To investigate the effects of cigarette smoking on ovarian function and fertility in women undergoing assisted reproduction cycles. Methods We assessed the effects of smoking on ovarian function and fertility in a cohort of 499 women. Questionnaires were designed to quantify past smoking exposure and to determine whether the woman was smoking during the treatment cycle. Ovarian function characteristics and pregnancy rates were compared among current smokers, past smokers, and nonsmokers. Results Compared with nonsmokers, both current and past smokers have reduced gonadotropin-stimulated ovarian function. A history of increasing tobacco exposure was associated with decreasing serum estradiol concentrations, numbers of retrieved oocytes, and numbers of embryos. On average, for every 10 pack-years of cigarette smoking, 2.5 fewer mature oocytes and 2.0 fewer embryos were obtained. Women who smoked during their treatment cycle had approximately a 50% reduction in implantation rate and ongoing pregnancy rate compared with women who had never smoked. Women who quit smoking before their treatment cycle had the same pregnancy rate as nonsmokers. Conclusion Cigarette smoking is associated with a prolonged and dose-dependent adverse effect on ovarian function. Smoking appears to have a more transient toxic effect on fertility, because current smokers, but not past smokers, had a markedly reduced pregnancy rate after treatment cycles compared with nonsmokers. Women should quit smoking before assisted reproduction cycles.


The Journal of Urology | 1998

Effect of exogenous testosterone on prostate volume, serum and semen prostate specific antigen levels in healthy young men

Christopher S. Cooper; Paul J. Perry; Amy E.T. Sparks; John H. MacIndoe; William R. Yates; Richard D. Williams

PURPOSE We investigate and define the effects of exogenous testosterone on the normal prostate. MATERIALS AND METHODS A total of 31 healthy volunteers 21 to 39 years old were randomized to receive either 100, 250 or 500 mg. testosterone via intramuscular injection once a week for 15 weeks. Baseline measurements of serum testosterone, free testosterone and prostate specific antigen (PSA) were taken at week 1. Semen samples were also collected for PSA content and prostate volumes were determined by transrectal ultrasound before testosterone injection. Blood was then drawn every other week before each testosterone injection for the 15 weeks, every other week thereafter until week 28 and again at week 40. After the first 15 weeks semen samples were again collected, and prostate volumes were determined by repeat transrectal ultrasound. RESULTS Free and total serum testosterone levels increased significantly in the 250 and 500 mg. dose groups. No significant change occurred in the prostate volume or serum PSA levels at any dose of exogenous testosterone. Total semen PSA levels decreased following administration of testosterone but did not reach statistical significance. CONCLUSIONS Despite significant elevations in serum total and free testosterone, healthy young men do not demonstrate increased serum or semen PSA levels, or increased prostate volume in response to exogenous testosterone injections.


Fertility and Sterility | 1999

Establishment of a successful donor embryo program: medical, ethical, and policy issues

Bradley J. Van Voorhis; Dan M Grinstead; Amy E.T. Sparks; Janice L Gerard; Robert F. Weir

OBJECTIVE To determine how couples prefer to dispose of their extra embryos and to establish a donor embryo program for the treatment of infertile couples. DESIGN Cohort study. SETTING University-based IVF program. PATIENT(S) Patients (n = 365) with cryopreserved embryos in storage for >2 years and eight patients who desired donated embryos for transfer. INTERVENTION(S) An IVF ethics committee was formed to discuss the ethical and policy issues involved in starting an embryo donation program and to establish program guidelines. Couples with embryos cryopreserved for > or = 2 years were contacted to determine their desires for disposition of embryos. Potential recipients of donated embryos were identified in our clinic, and donated embryos were transferred to these patients. MAIN OUTCOME MEASURE(S) Desires for embryo disposition and pregnancy rates. RESULT(S) Most couples elected either to continue storage of their embryos for future use (44%) or to discard their embryos (34%). A minority elected to donate their embryos either to infertile couples (11%) or for research (10%). Eight couples have had donated embryos transferred, and four have conceived ongoing pregnancies. CONCLUSION(S) Although only a small percentage of couples are willing to donate their embryos, the resulting number of embryos for use is substantial. Transfer of donated embryos results in a high pregnancy rate and is a cost-effective treatment of infertility.


Fertility and Sterility | 1997

Cost-effectiveness of infertility treatments: a cohort study

Bradley J. Van Voorhis; Amy E.T. Sparks; Brian D. Allen; Dale W. Stovall; Craig H. Syrop; Frederick K. Chapler

OBJECTIVE To determine the cost-effectiveness of infertility treatments. DESIGN Retrospective cohort study. SETTING Academic medical center infertility practice. PATIENT(S) All patients treated for infertility in a 1-year time span. INTERVENTION(S) Intrauterine inseminations, clomiphene citrate and IUI (CC-IUI), hMG and IUI (hMG-IUI), assisted reproductive techniques (ART), and neosalpingostomy by laparotomy. MAIN OUTCOME MEASURE(S) All medical charges and pregnancy outcomes associated with the treatments were obtained. Cost-effectiveness ratios defined as cost per delivery were determined for each procedure. The effects of a womans age and the number of spermatozoa inseminated on cost-effectiveness of the procedures was also determined. RESULT(S) Intrauterine inseminations, CC-IUI, and hMG-IUI have a similar cost per delivery of between


Fertility and Sterility | 1999

Decreased expression of the c-kit receptor is associated with increased apoptosis in subfertile human testes

Huai L. Feng; Jay I. Sandlow; Amy E.T. Sparks; Alexander Sandra

7,800 and


Fertility and Sterility | 2001

Decreased expression of the heat shock protein hsp70-2 is associated with the pathogenesis of male infertility.

Huai L. Feng; Jay I. Sandlow; Amy E.T. Sparks

10,300. All of these were more cost-effective than ART, which had a cost per delivery of


Journal of Assisted Reproduction and Genetics | 1992

Embryo Density and Medium Volume Effects on Early Murine Embryo Development

R.S. Canseco; Amy E.T. Sparks; R.E. Pearson; Francis C. Gwazdauskas

37,000. Assisted reproductive techniques in women with blocked fallopian tubes was more cost-effective than tubal surgery performed by laparotomy, which had a cost per delivery of

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Bradley J. Van Voorhis

Roy J. and Lucille A. Carver College of Medicine

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Craig H. Syrop

Roy J. and Lucille A. Carver College of Medicine

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Ginny L. Ryan

Roy J. and Lucille A. Carver College of Medicine

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Jay I. Sandlow

Medical College of Wisconsin

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Christina Wang

Los Angeles Biomedical Research Institute

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