Prospective evaluation of the impact of intermenstrual bleeding on natural fertility.

Journal Article (Clinical Trial;Journal Article)

OBJECTIVE: To evaluate the impact of an episode of intermenstrual bleeding on the probability of conception in a menstrual cycle (fecundability). DESIGN: Prospective, time-to-pregnancy cohort study. SETTING: Community-based cohort. PATIENT(S): Women trying to conceive, ages 30 to 44 years, without known infertility. INTERVENTION(S): Not applicable. MAIN OUTCOME MEASURE(S): Current cycle and subsequent cycle fecundability. RESULT(S): A total of 549 women provided 1,552 complete cycles for analysis. Intermenstrual and luteal bleeding were reported in 36% and 34% of cycles, respectively. Ninety-three percent of all intermenstrual bleeding was luteal. Cycles in which women had intermenstrual bleeding or luteal bleeding were statistically significantly less likely to result in conception (fecundability ratio [FR] 0.23; 95% confidence interval [CI], 0.16-0.34; and FR 0.22; 95% CI, 0.14-0.33). Women with an episode of intermenstrual and luteal bleeding had a statistically significant increase in the probability of pregnancy in the subsequent cycle (FR 1.61; 95% CI, 1.15-2.25; and FR 2.01; 95% CI, 1.52-2.87, respectively). CONCLUSION(S): Intermenstrual bleeding statistically significantly decreases the odds of conceiving in that cycle but does not appear to negatively impact a woman's immediate future reproductive potential. CLINICAL TRIAL REGISTRATION NUMBER: NCT01028365.

Full Text

Duke Authors

Cited Authors

  • Crawford, NM; Pritchard, DA; Herring, AH; Steiner, AZ

Published Date

  • May 2016

Published In

Volume / Issue

  • 105 / 5

Start / End Page

  • 1294 - 1300

PubMed ID

  • 26820771

Pubmed Central ID

  • 26820771

Electronic International Standard Serial Number (EISSN)

  • 1556-5653

Digital Object Identifier (DOI)

  • 10.1016/j.fertnstert.2016.01.015


  • eng

Conference Location

  • United States