The ClearPlan Easy™ Fertility Monitor* predicts the times of high potential fertility, i.e. the times when sexual intercourse is most likely to result in conception. The test procedure identifies the times of specified changes in the concentration of urinary hormone metabolites during each ovarian cycle. The results are displayed in terms of prior knowledge about the time-specific probabilities of conception. This paper contains a summary of the scientific background that led to the development of the ClearPlan Easy™ Fertility Monitor.
MayK: The Unipath personal contraceptive system. In: Natural Contraception Through Personal Hormone Monitoring (BonnarJ, ed). New York: The Parthenon Publishing Group, 1996; pp35–44
2.
BurgerHG: Estradiol: the physiological basis of the fertile period. Suppl Int J Gynaecol Obstet1989; 1: 5–9
3.
CollinsWP: Biochemical indices of potential fertility. Suppl Int J Gynaecol Obstet1989; 1: 35–43
4.
RoystonJP: Identifying the fertile phase of the human menstrual cycle. Stat Med1991; 10: 221–240
5.
World Health Organization: Temporal relationships between ovulation and defined changes in the concentration of plasma estradiol-17 beta, luteinizing hormone, follicle-stimulating hormone and progesterone. I. Probit analysis. Am J Obstet Gynecol1980; 138: 383–390
6.
World Health Organization: Temporal relationships between ovulation and defined changes in the concentration of plasma estradiol-17 beta, luteinizing hormone, follicle-stimulating hormone and progesterone. II. Histologic dating. Am J Obstet Gynecol1980; 139: 886–895
7.
World Health Organization: A prospective multicentre study to develop universal immunochemical tests for predicting the fertile period in women. Int J Fertil1985; 30: 18–30
8.
World Health Organization: Temporal relationships between indices of the fertile period. Fertil Steril1983; 39: 647–655
9.
TsafririA: Ovulation as a tissue remodelling process. Proteolysis and cumulus expansion. In: Tissue Renin-Angiotensin Systems (MukhopadhyayAKRaizadaMK, eds). New York: Plenum Press, 1995; pp121–139
10.
CampbellSBourneTHWaterstoneJReynoldsKMCrayfordTJJurkovicD: Transvaginal color flow imaging of the periovulatory follicle. Fertil Steril1993; 60: 433–438
11.
BränströmMZackrissonUHagströmH-GJosefssonBHellbergPGranbergS: Preovulatory changes of blood flow in different regions of the human follicle. Fertil Steril1998; 69: 435–442
12.
FlynnAMCollinsWPRoystonPBarbatoMMena-GonzalezPAlliendeME: Volumetric self-sampling of cervicovaginal fluid to determine potential fertility: a multicentre preeffectiveness study of the Rovumeter™. Hum Reprod1997; 12: 1826–1831
13.
MoghissiMSDabishDLevineJNeuhausO: Mechanism of sperm migration. Fertil Steril1964; 15: 15–24
14.
WilcoxAJWeinbergCRBairdDD: Timing of sexual intercourse in relation to ovulation. Effects on the probability of conception, survival of the pregnancy, and sex of the baby. N Engl J Med1995; 333: 1517–1521
15.
CollinsWP: The evolution of reference methods to monitor ovulation. Am J Obstet Gynecol1991; 165: 1994–1996
16.
CollinsWP: Indicators of potential fertility: scientific principles. In: Natural Conception Through Personal Hormone Monitoring (BonnarJ, ed). New York: The Parthenon Publishing Group, 1996; pp13–33
SamarajeewaPKellieAE: The radioimmunoassay of steroid glucuronides. The oestrogen C-3 glucuronide as haptens. Biochem J1975; 151: 369–376
19.
CollinsWPCollinsPOKilpatrickMJManningPAPikeJMTylerJP: The concentrations of urinary oestrone-3-glucuronide, LH and pregnanediol-3-glucuronide as indices of ovarian function. Acta Endocrinol1979; 90: 336–348
20.
World Health Organization: The measurement of steroid glucuronides as an index of the fertile period in women. J Steroid Biochem1982; 17: 695–702
21.
CollinsWPBranchCMCollinsPO: Ovulation prediction and detection by the measurement of steroid glucuronides. In: Research on Fertility and Sterility (Cortes-PrietoJda PazA CampasNeves-e-CastroM, eds). Lancaster: MTP Press Ltd, 1981; pp19–33
22.
MayK: Home monitoring with the ClearPlan Easy™ Fertility Monitor for fertility awareness. J Int Med Res2001; 29 (Suppl 1): 14A–20A
23.
CatalanRCastellanosJMPalominoTSentiMAntolinMGalardRM: Correlation between plasma estradiol and estrone-3-glucuronide in urine during the monitoring of ovarian induction therapy. Int J Fertil1989; 34: 271–275
24.
QueenanJTO'BrianGDBainsLMSimpsonJCollinsWPCampbellS: Ultrasound scanning of ovaries to detect ovulation in women. Fertil Steril1980; 34: 99–105
25.
BourneTHHagströmH-GHahlinMJosefssonBGranbergSHellbergP: Ultrasound studies of vascular and morphological changes in the human corpus luteum during the menstrual cycle. Fertil Steril1996; 65: 753–758
26.
BourneTHHagströmH-GGranbergSJosefssonBHahlinMHellbergP: Ultrasound studies of vascular and morphological changes in the human uterus after a positive self-test for the urinary luteinizing hormone surge. Hum Reprod1996; 11: 369–375
27.
BarrettJCMarshallJ: The risk of conception on different days of the menstrual cycle. Population Studies1969; 23: 455–461
28.
SchwarzDMacDonaldPDMHeuchelV: Fecundability, coital frequency and the viability of ova. Population Studies1980; 23: 455–461
29.
RoystonJP: Basal body temperature, ovulation and the risk of conception with special reference to the lifetimes of sperm and egg. Biometrics1982; 38: 397–406
30.
Ferreira-PobleteA: The probability of conception on different days of the cycle with respect to ovulation: an overview. Adv Contracept1997; 13: 83–95
31.
SchiphorstLEMCollinsWPRoystonJP: An estrogen test to determine the times of potential fertility in women. Fertil Steril1985; 44: 328–334
32.
HunterRHF: Human fertilization in vivo, with special reference to progression, storage and release of competent spermatozoa. Hum Reprod1987; 2: 329–333
33.
MasarottoGRomualdiC: Probability of conception on different days of the menstrual cycle: an ongoing exercise. Adv Contracept1997; 13: 105–115
34.
DomarADClappDSlawsbyEADusekJKesselBFreizingerM: Impact of group psychological interventions on pregnancy rates in infertile women. Fertil Steril2000; 73: 805–811