Changing trends in reproductive/lifestyle factors in UK women: descriptive study within the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS).

OBJECTIVE: There has been considerable interest in the impact of reproductive factors on health but there are little data on how these have varied over time. We explore trends in reproductive/lifestyle factors of postmenopausal British women by analysing self-reported data from participants of the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS). DESIGN: Prospective birth cohort analysis. SETTING: Population cohort invited between 2001 and 2005 from age-sex registers of 27 Primary Care Trusts in England, Wales and Northern Ireland and recruited through 13 National Health Service Trusts. PARTICIPANTS: 202 638 postmenopausal women aged 50-74 years at randomisation to UKCTOCS between April 2001 and October 2005. INTERVENTIONS: Women were stratified into the following six birth cohorts (1925-1929, 1930-1934, 1935-1939, 1940-1944, 1945-1949, 1950-1955) based on year of birth. Self-reported data on reproductive factors provided at recruitment were explored using tabular and graphical summaries to examine for differences between the birth cohorts. OUTCOME MEASURES: Trends in mean age at menarche and menopause, use of oral contraceptives, change in family size, infertility treatments, tubal ligation and hysterectomy rates. RESULTS: Women born between 1935 and 1955 made up 86% of the cohort. Median age at menarche decreased from 13.4 for women born between 1925 and 1929 to 12.8 for women born between 1950 and 1955. Increased use of the oral contraceptives, infertility treatments and smaller family size was observed in the younger birth cohorts. Tubal ligation rates increased for those born between 1925 and 1945, but this increase did not persist in subsequent cohorts. Hysterectomy rates (17-20%) did not change over time. CONCLUSIONS: The trends seen in this large cohort are likely to reflect the reproductive history of the UK female postmenopausal population of similar age. Since these are risk factors for hormone-related cancers, these trends are important in understanding the changing incidence of these cancers. TRIAL REGISTRATION NUMBER: International Standard Randomised Controlled Trial Number: 22488978.

Potential effect of the risk of ovarian cancer algorithm (ROCA) on the mortality outcome of the Prostate, Lung, Colorectal and Ovarian (PLCO) trial.

Recently, the Prostate, Lung, Colorectal and Ovarian (PLCO) Trial reported no mortality benefit for annual screening with CA-125 and transvaginal ultrasound (TVU). Currently ongoing is the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS), which utilizes the risk of ovarian cancer algorithm (ROCA), a statistical tool that considers current and past CA125 values to determine ovarian cancer risk. In contrast, PLCO used a single cutoff for CA125, based on current levels alone. We investigated whether having had used ROCA in PLCO could have, under optimal assumptions, resulted in a significant mortality benefit by applying ROCA to PLCO CA125 screening values. A best-case scenario assumed that all cancers showing a positive screen result earlier with ROCA than under the PLCO protocol would have avoided mortality; under a stage-shift scenario, such women were assigned survival equivalent to Stage I/II screen-detected cases. Updated PLCO data show 132 intervention arm ovarian cancer deaths versus 119 in usual care (relative risk, RR = 1.11). Forty-three ovarian cancer cases, 25 fatal, would have been detected earlier with ROCA, with a median (minimum) advance time for fatal cases of 344 (147) days. Best-case and stage-shift scenarios gave 25 and 19 deaths prevented with ROCA, for RRs of 0.90 (95% CI: 0.69-1.17) and 0.95 (95% CI: 0.74-1.23), respectively. Having utilized ROCA in PLCO would not have led to a significant mortality benefit of screening. However, ROCA could still show a significant effect in other screening trials, including UKCTOCS.