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Your Environment. Your Health.

Study Publications

Early Pregnancy Study (EPS)

Early Pregnancy Study (EPS)

The Early Pregnancy Study generated data that the Epidemiology Branch and its collaborators published in peer-reviewed journal articles. To find out more about the study, please click the following links to journal articles and abstracts.


  1. Jukic AM, McConnaughey DR, Weinberg CR, Wilcox AJ, Baird DD. Long-term recall of time to pregnancy. Epidemiology 27(5):705-11; 2016.
  2. Jukic AM, Calafat AM, McConnaughey DR, Longnecker MP, Hoppin JA, Weinberg CR, Wilcox AJ, Baird DD. Urinary Concentrations of Phthalate Metabolites and Bisphenol A and Associations with Follicular-Phase Length, Luteal-Phase Length, Fecundability, and Early Pregnancy Loss. Environmental health perspectives 2016 124(3):321-328. [Abstract]


  1. Li D, Wilcox AJ, Dunson D. Benchmark Pregnancy Rates and the Assessment of Post-coital Contraceptives: An Update. Contraception 91(4):344-9; 2015.


  1. Jukic AM, Baird DD, Weinberg CR, McConnaughey DR, Wilcox AJ. Length of human pregnancy and contributors to its natural variation. Hum Reprod 28(10):2848-55; 2013.


  1. Jukic AM, Weinberg CR, Baird DD, Wilcox AJ. The association of maternal factors with delayed implantation and the initial rise of urinary human chorionic gonadotrophin. Hum Reprod. 2011 26(4):920-6. [Abstract]


  1. Nepomnaschy PA, Weinberg CR, Wilcox AJ, Baird DD. Urinary hCG patterns during the week following implantation. Hum Reprod 2008;23:271-7. Epub 2008 Dec 14. [Abstract]


  1. Jukic AM, Weinberg CR, Baird DD, Wilcox AJ. Lifestyle and reproductive factors associated with follicular phase length. J Womens Health (Larchmt). 2007;16:1340-7. [Abstract]


  1. Promislow JH, Baird DD, Wilcox AJ, Weinberg CR. Bleeding following pregnancy loss before 6 weeks' gestation. Hum Reprod 2007;22:853-7. Epub 2006 Oct 27. [Abstract]


  1. McChesney R, Wilcox AJ, O'Connor JF, Weinberg CR, Baird DD, Schlatterer JP, McConnaughey DR, Birken S, Canfield RE. Intact hCG, free hCG beta subunit and hCG beta core fragment: Longitudinal patterns during early pregnancy. Hum Reprod 20:928-35; 2005. [Abstract]


  1. Wilcox AJ, Baird DD, Dunson DB, McConnaughey DR, Kesner JS, Weinberg CR. On the frequency of intercourse around ovulation: evidence for biological influences. Hum Reprod 19:1539-43; 2004. [Abstract] [Full Text] [download the PDF]


  1. Baird DD, Weinberg CR, McConnaughey DR, Wilcox AJ. Rescue of the corpus luteum in human pregnancy. Biol Reprod 68:448-56; 2003. [Abstract]
  2. Harville EW, Wilcox AJ, Baird DD, Weinberg CR. Vaginal bleeding in very early pregnancy. Hum Reprod 18:1944-7; 2003. [Abstract]


  1. Sayle AE, Wilcox AJ, Weinberg CR, Baird DD. A prospective study of the onset of symptoms of pregnancy. J Clin Epidemiol 55:676-80; 2002. [Abstract]


  1. Dunson DB, Weinberg CR, Baird DD, Kesner JS, Wilcox AJ. Assessing human fertility using several markers of ovulation. Statist Med 20:965-78, 2001. [Abstract]
  2. Dunson DB, Weinberg CR, Wilcox AJ. Modeling multiple ovulation, fertilization, and embryo loss in human fertility studies. Biostat 2:131-45; 2001. [Abstract]
  3. Wilcox AJ, Baird DD, Dunson D, McChesney R, Weinberg CR. The natural limits of pregnancy testing in relation to the expected menstrual period. JAMA 286:1759-61; 2001. [Abstract]
  4. Wilcox AJ, Dunson DB, Weinberg CR, Trussell J, Baird DD. Likelihood of conception with a single act of intercourse: providing benchmark rates for assessment of post-coital contraceptives. Contraception 63:211-5, 2001. [Abstract]


  1. Harlow SD, Baird DD, Weinberg CR, Wilcox AJ: Urinary estrogen patterns in long follicular phases. Hum Reprod 15:11-6, 2000. [Abstract]
  2. Wilcox AJ, Dunson D, Baird DD: The timing of the fertile window in the menstrual cycle: day-specific estimates from a prospective study. Brit Med J 321:1259-62; 2000. [Abstract] [Full Text]


  1. Baird DD, Weinberg CR, Zhou H, Kamel F, McConnaughey DR, Kesner JS, Wilcox AJ: Preimplantation urinary hormone profiles and the probability of conception in healthy women. Fertil Steril 71: 40-49, 1999. [Abstract]
  2. Dunson DB, Baird DD, Wilcox AJ, Weinberg CR: Day-specific probabilities of clinical pregnancy based on two studies with imperfect measures of ovulation. Hum Reprod 14:1835-1839, 1999. [Abstract]
  3. Wilcox AJ, Baird DD, Weinberg CR: Time of implantation of the conceptus and loss of pregnancy. New Engl J Med 340:1796-9, 1999. [Abstract]


  1. Kesner JS, Knecht EA, Krieg EF, Wilcox AJ, OíConnor JF: Detecting preovulatory luteinizing hormone surges in urine. Hum Reprod 13: 15-21; 1998. [Abstract]
  2. Weinberg CR, Wilcox AJ, Baird DD, Gladen B: The probability of conception as related to the timing of intercourse around ovulation. Genus LIV 3-4: 129-142, 1998.
  3. Wilcox AJ, Weinberg CR, Baird DD: Post-ovulatory ageing of the human oocyte and embryo failure. Hum Reprod 13: 394-97; 1998. [Abstract]


  1. Baird DD, Wilcox AJ, Weinberg CR, Kamel F, McConnaughey DR, Musey PI, Collins DC: Preimplantation hormonal differences between the conception and non-conception menstrual cycles of 32 normal women. Hum Reprod 12: 2607-13; 1997. [Abstract]


  1. Zhou H, Weinberg CR, Wilcox AJ, Baird DD: A random effects model for cycle viability in fertility studies. JASA 91: 1413-1422, 1996.


  1. Baird DD, McConnaughey DR, Weinberg CR, Musey PI, Collins DC, Kesner, JS, Knecht EA, Wilcox AJ: Application of a method for estimating day of ovulation using urinary estrogen and progesterone metabolites. Epidemiol 6: 547-50; 1995. [Abstract]
  2. Weinberg CR, Wilcox AJ: A model for estimating the potency and survival of human gametes in vivo. Biometrics 51:405-12; 1995. [Abstract]
  3. Weinberg CR, Wilcox AJ, Baird DD: The sex of the baby may be related to the length of the follicular phase in the conception cycle. Hum Reprod 10:304-7; 1995. [Abstract]
  4. Wilcox AJ: Molecular epidemiology: collision of two cultures. Epidemiol 6: 561-2, 1995.


  1. Weinberg CR, Gladen BC, Wilcox AJ: Models relating the timing of intercourse to the probability of conception and the sex of the baby. Biometrics 50:358-67, 1994. [Abstract]
  2. Weinberg CR, Moledor E, Baird DD, Wilcox AJ: Is there a seasonal pattern in early pregnancy loss? Epidemiol 5:484-89; 1994. [Abstract]


  1. Wilcox AJ, Weinberg CR, Baird DD, Canfield RE: Endocrine detection of conception and early foetal loss. In Gray RH (ed.): Biomedical and Demographic Determinants of Reproduction. Clarendon Press, Oxford, 1993, 316-28.


  1. Weinberg CR, Hertz-Picciotto I, Baird DD, Wilcox AJ: Efficiency and bias in studies of early pregnancy loss. Epidemiol 3:17-22, 1992. [Abstract]


  1. Baird DD, Weinberg CR, Wilcox AJ, McConnaughey DR, Musey PI: Using the ratio of urinary estrogen and progesterone metabolites to estimate day of ovulation. Statist Med 10:255-66, 1991. [Abstract]
  2. Baird DD, Weinberg CR, Wilcox AJ, McConnaughey DR, Musey PI, Collins DC: Hormonal profiles of natural conception cycles ending in early, unrecognized pregnancy loss. J Clin Endocrinol Metab 72:793-800, 1991. [Abstract]
  3. Wilcox AJ: Early pregnancy. In Kiely M (ed.): Reproductive and Perinatal Epidemiology, CRC Press, 1991, 63-75.


  1. Wilcox AJ, Weinberg CR, Baird DD: Risk factors for early pregnancy loss. Epidemiol 1:382-85, 1990. [Abstract]


  1. Canfield RE, O'Connor JF, Chen Y, Krichevsky A, Birken S, Wilcox AJ: The clinical utility of the measurement of urinary hCG and its fragments. In Bellet D, Bidart J-M (eds.): Structure-Function Relationship of Gonadotropins. Serono Symposia Publications, Raven Press, NY, 1989, 297-311.
  2. Hornsby PP, Wilcox AJ: Validity of questionnaire information on frequency of coitus. Am J Epidemiol 130:94-99, 1989. [Abstract]
  3. Weinberg CR, Wilcox AJ, Baird DD: Reduced fecundability in women with prenatal exposure to cigarette smoking. Am J Epidemiol 129:1072-78, 1989. [Abstract]
  4. Wilcox AJ, Baird DD, Weinberg CR: Do women with childhood exposure to cigarette smoking have increased fecundability? Am J Epidemiol 129:1079-83, 1989. [Abstract]


  1. Canfield RE, O'Connor JF, Birken S, Krichevsky A, Wilcox AJ, Lustbader J, Moyle W: HCG immunochemistry as related to clinical applications. In Mochizuki M, Hussa R (eds.): Placental Protein Hormones. Elsevier Science Publishers, 1988, 55-61.
  2. Canfield RE, O'Connor JF, Wilcox AJ: Measuring human chorionic gonadotropin for detection of early pregnancy loss. Reprod Toxicol 2:199-203, 1988. [Abstract]
  3. Wilcox AJ, Weinberg CR, Baird DD: Caffeinated beverages and decreased fertility. Lancet ii:1453-57, 1988.
  4. Wilcox AJ, Weinberg CR, O'Connor JF, Baird DD, Schlatterer JP, Canfield RE, Armstrong EG, Nisula BC: Incidence of early loss of pregnancy. New Engl J Med 319:189-94, 1988. [Abstract]


  1. Canfield RE, O'Connor JF, Birken S, Krichevsky A, Wilcox AJ: Development of an assay for a biomarker of pregnancy and early fetal loss. Environ Health Perspect 74:57-66, 1987. [Abstract]
  2. Wilcox AJ, Baird DD, Weinberg CR, Armstrong EG, Musey PI, Wehmann RE, Canfield RE: The use of biochemical assays in epidemiologic studies of reproduction. Environ Health Perspect 75:29-35, 1987. [Abstract]
  3. Wilcox AJ, Weinberg CR, Armstrong EG, Canfield RE: Urinary human chorionic gonadotropin among intrauterine device users: detection with a highly specific and sensitive assay. Fertil Steril 47:265-69, 1987. [Abstract]


  1. Wilcox AJ, Weinberg CR, Wehmann RE, Armstrong EG, Canfield RE, Nisula BC: Measuring early pregnancy loss: laboratory and field methods. Fertil Steril 44:366-74, 1985. [Abstract]
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