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Bleeding following pregnancy loss before 6 weeks' gestation.
J H E Promislow1, D D Baird, A J Wilcox
1Social and Scientific Systems, National Institute of Environmental Health Sciences, Durham, NC 27703, USA. promisl1@niehs.nih.gov
Human Reproduction (Oxford, England)
|October 31, 2006
Summary
Bleeding after early pregnancy loss is similar to typical menstruation, making it hard to recognize. Pregnancies lost very early had less bleeding than usual, possibly due to endometrial factors.
Area of Science:
- Reproductive Endocrinology
- Gynecology
- Early Pregnancy Complications
Background:
- Early pregnancy loss (before 6 weeks' gestation) is common.
- Bleeding patterns following early pregnancy loss are not well-documented.
- Comparison with typical menstruation is lacking.
Purpose of the Study:
- To compare bleeding patterns in women experiencing pregnancy loss before 6 weeks' gestation with their usual menstrual bleeding.
- To investigate the characteristics of bleeding associated with very early pregnancy loss.
Main Methods:
- Women tracked daily bleeding using pad and tampon counts.
- Urine samples were collected daily during the fertile period.
- Data from 36 women with early pregnancy loss and at least one non-pregnant cycle were analyzed.
Main Results:
- Mean bleeding duration after loss was 0.4 days longer than typical menses (P=0.01), mainly due to extended light bleeding.
- Total pad and tampon usage did not significantly increase.
- Bleeding was less than usual for very short pregnancies and more than usual for longer pregnancies.
Conclusions:
- Bleeding following early pregnancy loss is generally similar to menstruation and may not be recognized as a loss.
- Reduced bleeding in very early losses might indicate underlying endometrial factors.
- Further research into endometrial contributions to early pregnancy loss is warranted.
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