Healthcare Professionals Clearblue Fertility & Ovulation Products

Clearblue® Fertility & Ovulation Products

Fertility and Ovulation Tests

Clearblue® offers a range of ovulation test and fertility products, all of which monitor luteinizing hormone (LH) in urine to identify the time of peak fertility.

The Clearblue® Fertility Monitor, Clearblue® Connected Ovulation Test System and Clearblue® Advanced Digital Ovulation Test also measure another key hormone, estrogen (estrone-3-glucuronide) to identify the period of high fertility that occurs prior to the LH surge. Monitoring these two hormones helps women identify the fertile days of their cycle enabling them to time intercourse on the days when conception is most likely.

How urinary LH and E3G can be used to identify fertile days

There are only a few days per cycle when a woman is fertile and can conceive. Evidence shows that this time of increased fertility usually spans 6 days, starting approximately 5 days prior to ovulation and ending on the day of ovulation itself.1 The 6-day fertile period is affected by:

  • The lifespan of the egg, which is up to 24 hours after ovulation
  • The lifespan of sperm which is more variable. The median is 1.5 days, but sperm can survive up to 5 days in the sperm supportive mucus found in the fertile days of the cycle. Sperm survival is therefore dependent on the type and quantity of the mucus within the cervix, and the quality of the sperm itself.

The two most fertile days of this 6-day window are known as peak fertility days. These peak fertile days are the day prior to ovulation and the day that ovulation takes place.2

Studies show that a surge in LH level occurs 24-36 hours prior to ovulation,2 and that this LH surge is an accurate and reliable marker of impending ovulation.3-7 The urinary LH surge pinpoints the two peak fertile days of a woman's cycle, with intercourse on these days being shown to be associated with the highest likelihood of conception.1

In the days leading up to the LH surge, estradiol levels rise gradually, reaching a threshold that triggers the pre-ovulatory LH surge. Tracking E3G, the urinary metabolite of estradiol, allows women to identify the days of high fertility leading up to ovulation, where conception is also possible, and this also gives them advanced notice of their peak fertile days. Data show that women who are aware of their fertile days have an increased likelihood of conceiving.8,9​

Furthermore, estradiol stimulates secretion of cervical mucus that is favorable for the survival and transport of sperm. The rise in plasma estradiol corresponds closely to the appearance of sperm-supportive cervical mucus.10 Therefore, intercourse during the 6-day fertile period may lead to conception, as sperm can survive for a number of days. 

Day of Cycle

Typical changes in urinary E3G and LH relative during the menstrual cycle

The Clearblue® Fertility Monitor is a unique innovation proven to help women conceive sooner than not using any method.a1,8,11-13 It identifies changes in urine levels of LH and E3G to typically identify up to 6 days of high and peak fertility per cycleb. This makes the Clearblue® Fertility Monitor the most advanced home method to help women maximize their chances of conception.  Clinical studies have found urinary measurements by Clearblue® Fertility Monitor closely reflect serum concentrations of the hormones6 and the LH surge detection by the monitor accurately predicts ovulation.5 The Clearblue® Fertility Monitor now features an intuitive touch screen display and other features that make it an effective and easy-to-use aid for women trying to conceive.  The monitor also stores up to 6 cycles of data which can then be retrieved and shared with Healthcare Professionals.

  • aUsing the Clearblue® Fertility Monitor to identify the most fertile days can help women get pregnant sooner than not using any method.
  • bNumber of fertile days will vary. In a German study of 149 cycles, Monitor results correlated with serum hormone levels and ultrasound observed ovulation.5


The Clearblue® Connected Ovulation Test System is the first and only dual-hormone ovulation test, now with smartphone app connectivity.  It combines a unique system that tracks two key fertility hormones with the convenience of an app, providing women with the accuracy of an ovulation test on their phonec, maximizing their chances of conceiving in a way like never before.

  • cOver 99% accurate at detecting the LH surge


The Clearblue® Advanced Digital Ovulation Test accurately tracks a woman’s personal menstrual cycle to identify a wider fertile window than other home ovulation tests, by tracking the changing levels in the urinary metabolites of E3G and LH. By measuring these 2 hormones, the Clearblue®Advanced Digital Ovulation Test typically identifies 4 or more fertile days, more than any other ovulation test, for more opportunities to get pregnant naturally.14  The Clearblue® Advanced Digital Ovulation Test is more than 99% accurate at detecting the LH surge.15  The digital display shows an unmistakable result in the form of a smiley face when a fertile day is detected.

The Clearblue® Digital Ovulation Test is over 99% accurate in detecting the LH surge.16 The Clearblue® Digital Ovulation Test identifies the two most fertile days by detecting this pre-ovulatory LH surge. It is a simple home ovulation test kit, which provides easy-to-read, easy-to-understand digital results for more accurate reading in consumers' hands.17

  • 1Wilcox AJ, Weinberg CR, Baird DD. 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 Med 1995 Dec 7;333(23):1517-21.
  • 2Ferreira-Poblete A. The probability of conception on different days of the cycle with respect to ovulation: an overview. Adv Contracept 1997 Jun;13(2-3):83-95.
  • 3Corson SL. Self-prediction of ovulation using a urinary luteinizing hormone test. J Reprod Med 1986;31(8 Suppl):760-3.
  • 4Guida M, Tommaselli GA, Palomba S, Pellicano M, Moccia G, Di Carlo C, et al. Efficacy of methods for determining ovulation in a natural family planning program. Fertil Steril 1999;72(5):900-4.
  • 5Behre HM, Kuhlage J, Gassner C, Sonntag B, Schem C, Schneider HP, et al. Prediction of ovulation by urinary hormone measurements with the home use ClearPlan Fertility Monitor: comparison with transvaginal ultrasound scans and serum hormone measurements. Hum Reprod 2000;15(12):2478-82.
  • 6Tanabe K, Susumu N, Hand K, Nishii K, Ishikawa I, Nozawa S. Prediction of the potentially fertile period by urinary hormone measurements using a new home-use monitor: comparison with laboratory hormone analyses. Hum Reprod 2001;16(8):1619-24.
  • 7Guermandi E, Vegetti W, Bianchi MM, Uglietti A, Ragni G, Crosignani P. Reliability of ovulation tests in infertile women. Obstet Gynecol 2001;97(1):92-6.
  • 8Hilgers TW, Daly KD, Prebil AM, Hilgers SK. Cumulative pregnancy rates in patients with apparently normal fertility and fertility-focused intercourse. J Reprod Med 1992 Oct;37(10):864-6.
  • 9Stanford JB, Dunson DB. Effects of sexual intercourse patterns in time to pregnancy studies. Am J Epidemiol 2007 May 1;165(9):1088- 95.
  • 10Burger, HG. Estradiol: the physiological basis of the fertile period. Int J Gynecol Obstet 1989; Suppl 1:5-9.
  • 11Robinson J., et al. Increased pregnancy rate with use of Clearblue® Easy Fertility Monitor. Fertility and Sterility. (2007) 87: 329–34. †
  • 12Robinson JE, Ellis JE. Mistiming of intercourse as a primary cause of failure to conceive: results of a survey on use of a home-use fertility monitor. Curr Med Res Opin 2007;23(2):301-6
  • 13Stanford JB, White GL and Hatasaka H. Timing Intercourse to Achieve Pregnancy: Current Evidence. American College of Obstetrics and Gynecologists (2002) 100: 1333-1341
  • 14SPD Data on file.  In a study of 87 women,4 or more fertile days were identified in 80% of cycles using actual cycle length.
  • 15SPD Data on file.  Study found >99% agreement with AutoDELFIA reference method in 100 cycles (all cycles had LH surge >40mIU/ml)
  • 16SPD data on file. Clearblue® Digital Ovulation Test has been shown to be 99% accurate when compared to a reference method in laboratory studies using urine samples from 123 cycles in which the LH surge was identified by a reference method.
  • 17Johnson S, Ellis J, Godbert S, Ali S, Zinaman M. Comparison of a digital ovulation test with three popular line ovulation tests to investigate user accuracy and certainty. Expert Opin Med Diagn 2011;5:467-473.