Time filter

Source Type

Bedford, United Kingdom

Johnson S.,SPD Development Company Ltd | Ellis J.,SPD Swiss Precision Diagnostics GmbH | Godbert S.,SPD Swiss Precision Diagnostics GmbH | Ali S.,SPD Swiss Precision Diagnostics GmbH | Zinaman M.,Caritas St Elizabeths Medical Center
Expert Opinion on Medical Diagnostics | Year: 2011

Objectives: To determine the accuracy and certainty with which volunteers interpreted results of a digital ovulation test, Clearblue digital ovulation test (CB-DOT), compared with three home use non-digital visual ovulation tests: Clearblue ovulation test (CB-OT), First Response (FR) and Answer (AN). Methods: A total of 72 female volunteers aged 18 45 years interpreted test results from each of the four ovulation tests to determine the day of the luteinising hormone surge in 40 individual menstrual cycles. We used urine previously collected from 25 volunteers. The accuracy with which volunteers interpreted the test results was calculated by comparing their results with results obtained by trained technicians using a blinded test regime. For each of the four tests, volunteers were also asked to rate seven attributes of certainty and eight attributes of preference. The primary objective was to compare the accuracy with which volunteers read results from CB-DOT when compared to three visual-based line ovulation tests. Results: A significantly higher percentage of volunteers/technicians agreed on the interpretation of the results from CB-DOT (97.3%) than for CB-OT (83.5%; p = 0.0153), AN (73%; p = 0.0011) or FR (64.3%; p = 0.0001). CB-DOT was also found to have significantly better Likert scores than CB-OT, FR and AN for all seven attributes of certainty and was the test that 97.2% of volunteers preferred. Conclusions: Women can misread the results of line ovulation tests. Over 97% of volunteers correctly read the result of CB-DOT. CB-DOT was also the test that women read with most certainty and the test that most users preferred. © 2011 Informa UK, Ltd. Source

Sowers M.R.,University of Michigan | Zheng H.,University of Michigan | Greendale G.A.,University of California at Los Angeles | Neer R.M.,Massachusetts General Hospital | And 4 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2013

Objective: Our objective was to characterize changes in bone resorption in relation to the final menstrual period (FMP), reproductive hormones, body mass index (BMI), and ethnicity. Methods: Urinary type I collagen N-telopeptide (NTX), estradiol, and FSH levels were measured annually for up to 8 years spanning the menopause transition in 918 African American, Chinese, Japanese, or Caucasian women. Results: Urinary NTX began to increase sharply about 2 years before the FMP, reaching its peak level about 1 to 1.5 years after the FMP. NTX levels declined modestly from 2 to 6 years after the FMP but remained about 20% higher than before the menopause transition. The sharp rise in FSH occurred in conjunction with a sharp decline in estradiol and shortly after FSH levels began increasing rapidly. The mean increase in urinary NTX across the menopause transition was greatest in women with BMI <25 kg/m2and smallest in women with BMI >30 kg/m2. Increases in NTX were greatest in Japanese women and smallest in African Americans. These differences were attenuated, but not eliminated, when analyses were adjusted for covariates, particularly BMI. Summary: During the menopause transition, a decline in ovarian function beginning about 2 years before the FMP is followed by an increase in bone resorption and subsequently by bone loss. The magnitude of the increase in bone resorption is inversely associated with BMI. Ethnic differences in changes in bone resorption are attenuated, but not eliminated, by adjustment for BMI. Ethnic differences in BMI, and corresponding ethnic differences in bone resorption, appear to account for much of the ethnic variation in perimenopausal bone loss. Copyright © 2013 by The Endocrine Society. Source

Gnoth C.,Green ivf | Gnoth C.,University of Cologne | Johnson S.,SPD Development Company Ltd
Geburtshilfe und Frauenheilkunde | Year: 2014

The first home pregnancy test was introduced in 1976. Since then, pregnancy tests have become the most common diagnostic assay used at home. Pregnancy tests use antibodies to detect human chorionic gonadotropin (hCG). It is an ideal marker of pregnancy since it rises rapidly and consistently in early pregnancy and can be detected in urine. The most advanced home pregnancy test currently available assesses the level of hCG found in urine and claims to provide women with reliable results within just a few weeks of pregnancy. Today, over 15 different types of home pregnancy test are available to buy over the counter in Germany. Many tests claim to be highly accurate and capable of detecting pregnancy before the next monthly period is due, although claims such as 8 days prior to menstruation are unrealistic. However, users and healthcare professionals should be aware that, although all are labelled as CE, there are currently no standard criteria for testing performance and claims. This review provides an overview of the development of home pregnancy tests and the data on their efficacy together with an analysis of published data on the accuracy of hCG for the detection of early pregnancy and studies on the use of home-based pregnancy tests. Preliminary data on some home pregnancy tests available in Germany are presented which indicate that many results do not match the claims made in the package insert. Healthcare professionals and women should be aware that some of the claims made for home pregnancy tests are inconsistent and that common definitions and testing criteria are urgently needed. © Georg Thieme Verlag KG Stuttgart New York. Source

Larsen J.,George Washington University | Buchanan P.,George Washington University | Buchanan P.,Foundation Medicine | Johnson S.,SPD Development Company Ltd | And 2 more authors.
International Journal of Gynecology and Obstetrics | Year: 2013

Objective To compare gestational age (GA) estimates in early pregnancy, determined by last menstrual period (LMP), human chorionic gonadotropin (hCG) concentration, ultrasound crown-rump length (Hadlock formula), and ovulation day (luteinizing hormone surge plus 1 day). Methods Female volunteers seeking to conceive (at 5 US sites) collected daily early-morning urine for up to 3 menstrual cycles. Pregnant women underwent ultrasound dating scans. Conception cycle urine was quantitatively assessed for luteinizing hormone and hCG. Summary statistics for GA using each reference method were determined (n = 131). Results Correlation between GA determined by ultrasound and ovulation day was excellent (maximum difference 10 days); however, pregnancies dated by ultrasound were 3 days advanced. The difference between LMP estimates and estimates based on ovulation day or ultrasound was 9 and 12 days, respectively. A uniform rise in hCG on each day of pregnancy was seen using all reference methods. The accuracy of hCG measurement in determining the week since conception was more than 93%. Conclusion Methods for establishing pregnancy duration vary in their accuracy and their GA estimates. The rise in hCG concentration in early pregnancy is uniform and therefore hCG levels provide the most accurate, early estimation of GA in single, viable pregnancies. ClinicalTrials.gov: NCT01077583 © 2013 International Federation of Gynecology and Obstetrics. Source

Tiplady S.,SPD Development Company Ltd | Jones G.,University of Sheffield | Campbell M.,University of Sheffield | Johnson S.,SPD Development Company Ltd | Ledger W.,University of New South Wales
Human Reproduction | Year: 2013

Study Question Does the use of a digital home ovulation test have any effect on the level of stress in women seeking to conceive? Summary Answer No difference was found in levels of stress between women using digital ovulation tests to time intercourse compared with women who were trying to conceive without any additional aids: in addition, their use did not negatively impact time to conception in users but may provide additional benefits, including an increased understanding of the menstrual cycle, reassurance and confidence in focusing conception attempts to the correct time in the cycle. What is Known Already It has been suggested that timing of intercourse in such a way that it coincides with ovulation by using ovulation tests can lead to emotional distress; however, no study has been conducted to investigate this hypothesis specifically, until now. Study Design, Sizeand DurationThe study was performed over two complete menstrual cycles as a prospective, randomized, controlled trial including quantitative and qualitative Methods . The intervention (test) group were given digital ovulation tests to time intercourse to the most fertile time of the cycle and the control group were provided with the current National Institute for Health and Clinical Excellence guidelines for increasing the chances of conception (intercourse every 2-3 days) and asked not to use any additional Methods to time when ovulation occurs. Participants/Materials, Setting and Methods A total of 210 women who were seeking to conceive were recruited from the general UK population. A total of 115 women were randomized to the test group and 95 to the control group through block randomization. The positive and negative affect schedule (PANAS) and the Perceived Stress Scale (PSS) were used to measure subjective stress levels, the Short-Form 12 health survey was used as a measure of general health and well-being and urine samples were measured for biochemical markers of stress including urinary cortisol. Qualitative data were collected in the form of a telephone interview upon study completion. Main Results AND THE ROLE OF CHANCEThere was no evidence for a difference either in total stress as measured using the PSS or in total positive or negative affect using the PANAS questionnaire between the test and control groups at any time point for the duration of the study. During cycle 1, for example, on Day 6, the difference in total stress score (test-control) was-0.62 [95% confidence interval (CI)-2.47 to 1.24] and on the day of the LH surge, it was 0.53 (95% CI-1.38 to 2.44). In addition, no correlation was observed between time trying to conceive and levels of stress, or between age and levels of stress, and no evidence was found to show that stress affected whether or not a pregnancy was achieved. There is also no evidence that the biochemistry measurements are related to whether a pregnancy was achieved or of a difference in biochemistry between the treatment groups. The use of digital ovulation tests did not negatively affect time to conception and with an adequately sized study, could potentially show improvement. To ensure that the results of this study were not affected by chance, we used a number of different Methods for measuring stress, each of which had been independently validated. Limitations and Reasons for CautionRandomization occurred before the start of the study because of the need to provide the ovulation tests in readiness for Day 6 of the first cycle. As a consequence, a number of women fell pregnant during this period (22 and 13 in the test and control groups, respectively). A further 15 women were either lost to follow-up or withdrew consent prior to study start. Pregnancy rate was higher overall in the test group, so to ensure that there were sufficient data from women who failed to become pregnant in the test group, we implemented an additional biased recruitment. This second cohort may have been different from the first, although no significant differences were observed between the two phases of recruitment for any of the information collected upon admission to the study. Wider Implications of the Findings Women who seek medical advice while trying to conceive should not be discouraged by health care professionals from using digital ovulation tests in order to time intercourse. The cohort of women recruited to this study initially had no evidence of infertility and were looking to conceive in a non-medical setting. A separate study to assess the impact of home ovulation tests in a subfertile population would be of interest and complementary to the present study. Study Funding/Competing Interest SThis study was funded by SPD Swiss Precision Diagnostics, GmbH, manufacturer of Clearblue® pregnancy and ovulation tests. SPD Development Company Ltd is a wholly owned subsidiary of SPD Swiss Precision Diagnostics GmbH; together referred to as SPD. Trial Registration Number NCT01084304 (www.clinicaltrials.gov). © 2012 The Author. Source

Discover hidden collaborations