News Release

New Clearblue® Study Finds Increased Chance of Pregnancy from Sex Two Days Before Ovulation

Women using Clearblue ® Advanced Digital Ovulation Test to identify their fertile window and target intercourse increased their likelihood of pregnancy

Thursday, April 26, 2018 4:00 pm EDT



Public Company Information:


New Clearblue® Study Finds Increased Chance Of Pregnancy from Sex Two Days Before Ovulation

CINCINNATI--(BUSINESS WIRE)--Clearblue®, the #1 OB-GYN-recommended Ovulation Test Brand1, reveals new data in ovulation showing that the Clearblue® Advanced Digital Ovulation Test maximizes chances of becoming pregnant naturally by helping women target intercourse effectively. Results from a new study showed that women who had intercourse two days before ovulation, a wider fertile window which only the Clearblue® Ovulation Test Brand can detect, increased their chances of pregnancy by 23.6 percent2. This new data analysis will be presented as a poster at the 2018 American College of Obstetricians and Gynecologists (ACOG) Annual Clinical and Scientific Meeting taking place in Austin, Texas, April 27 – April 30.

In the study, researchers at the Clearblue® Innovation Center examined intercourse patterns in 2,113 trying to conceive (TTC) women in the United Kingdom using the Clearblue® Advanced Digital Ovulation Test and examined the likelihood of pregnancy in relation to timing. The women used the ovulation test to time intercourse while keeping a diary detailing when they had intercourse and also collected daily urine samples for one menstrual cycle.

Key findings included2:

  • By using the Clearblue® Advanced Digital Ovulation Test, women targeted intercourse effectively to the fertile window, increasing their chances of pregnancy with successful timing.
  • Intercourse on the days prior to the Luteinizing Hormone (LH) surge is identifiable only through measuring a second hormone, estrogen. Clearblue® is the only Ovulation Test Brand that is capable of measuring two hormones. In the study, by adding these two extra days, there was an increased likelihood of pregnancy of 18.5 percent for intercourse on the day before the LH surge and an increased likelihood of pregnancy of 23.6 percent for intercourse two days before the LH surge.

“We want to give women accurate information to understand and identify their fertile window. This study reinforces that the Clearblue® Advanced Digital Ovulation Test maximizes the chances of conceiving by detecting a woman’s individual fertile window and, with more key days identified, it highlights more opportunities to get pregnant than any other ovulation test on the market,” said Dr. Sarah Johnson, author of the study and Clinical Research Director, Clearblue® .

The fertile window typically lasts for six days, ending at ovulation. Intercourse during this time period is essential for natural conception3. However, studies have shown that 50 percent of couples could be TTC on the wrong days4. The Clearblue® Advanced Digital Ovulation Test is the only brand to typically identify four or more fertile days, more than any other ovulation test5. It identifies a wider fertile window by accurately tracking two key fertility hormones, estrogen and LH (with over 99 percent accuracy6), while all other ovulation tests only measure one hormone (LH), adding more opportunities to conceive. The Clearblue® Advanced Digital Ovulation Test is more accurate than calendar and temperate methods at predicting the most fertile days7.

“Women have many options that claim to enhance their chances of getting pregnant. This study clearly shows that the use of a dual-hormone ovulation test is their best choice,” said Michael J. Zinaman, MD FACOG FACS, Professor of Obstetrics and Gynecology, Albert Einstein College of Medicine.

Clearblue® continues to be at the forefront of innovation in the ovulation testing category. The Clearblue® Advanced Digital Ovulation Test was recently awarded the ‘Best TTC Tech’ in the 2017 What to Expect Awards. The awards honor the very best in pregnancy with more than 130,000 votes from parents and the What to Expect community. In addition, the Clearblue® Connected Ovulation Test System, the brand’s latest innovation in ovulation testing, which pairs the accuracy of the Clearblue® Advanced Digital Ovulation Test with the convenience of an app, won the Red Dot Award: Product Design 2018. With more than 6,300 submissions from 59 countries, the panel of experts who judges the Red Dot Award gives the internationally recognized seal of quality only to products that win them over with their high design quality, innovation and functionality, among other criteria.

The Clearblue® Advanced Digital Ovulation Test and the Clearblue® Connected Ovulation Test System are available at major retailers across the U.S.

For more information on Clearblue® visit

About Clearblue®

Clearblue® is the world’s #1-selling brand in home pregnancy and fertility testing8. The Clearblue® product range is built on a strong foundation of peer-reviewed science and consumer understanding. Clearblue® products are also trusted and recommended by doctors, many of whom recognize that Clearblue® is supported by over 30 years of expertise, quality, and innovation in consumer diagnostics. Clearblue® offers a complete line of products to help a woman better understand her body’s ovulation cycle and identify peak fertility days to maximize her chances of getting pregnant. The Clearblue® family of products includes the Clearblue® Fertility Monitor, Clearblue® Advanced Digital Ovulation Test, Clearblue® Connected Ovulation Test System, Clearblue® Digital Ovulation Test, Clearblue® Easy Ovulation Test, Clearblue® Digital Pregnancy Test, and Clearblue® Rapid Detection Pregnancy Test. For more information visit

About Procter & Gamble

P&G serves consumers around the world with one of the strongest portfolios of trusted, quality, leadership brands, including Always®, Ambi Pur®, Ariel®, Bounty®, Charmin®, Crest®, Dawn®, Downy®, Fairy®, Febreze®, Gain®, Gillette®, Head & Shoulders®, Lenor®, Olay®, Oral-B®, Pampers®, Pantene®, SK-II®, Tide®, Vicks®, and Whisper®. The P&G community includes operations in approximately 70 countries worldwide. Please visit for the latest news and information about P&G and its brands.


1 Data on file. Research into recommendation of Ovulation Tests & Fertility Monitors with 204 US Ob-Gyns. (Kantar Health, 2011).
2 Johnson S., Marriott L., et al. “Increased likelihood of pregnancy from sex on the two days before ovulation” (2018).
3 Wilcox A, Weinberg C, and Baird D. N Engl J Med. (1995) 333:1517-1521.
4 Johnson SR, Foster L and Ellis J. Women’s knowledge regarding ovulation and most likely time of conception. Human Reproduction (2011) 26: i236.
5 In a study of 87 women, 4 or more fertile days were identified in 80% of cycles using actual cycle length (2012).
6 SPD Data on file. Study found >99% agreement with AutoDELFIA® reference method in 100 cycles (all cycle had LH surge >40mIU/ml).
7 Comparing a simple calendar method to likelihood of conducting a test on LH surge day (Ellis J. et al. Hum Repro (2011) 26: i76.).
8 In home pregnancy & fertility tests. Based on international sales in nearly 20 countries compiled using independent market research data.


P&G Personal Health Care North America & Global Communications
Velvet Gogol Bennett, 513-634-5576
MSL New York
Suzanne Lyons, 917-943-6334

Multimedia Files:

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Clearblue® Advanced Digital Ovulation Test (Photo: Business Wire)
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Clearblue® Connected Ovulation Test System – Red Dot Design Award Winner 2018 (Photo: Business Wire)
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