Battledore Placenta and Vaginal Bleeding
Battledore placenta (marginal cord insertion) is not a recognized cause of vaginal bleeding during pregnancy. This anatomical variant describes the umbilical cord inserting at the placental margin rather than centrally, but it does not directly cause maternal vaginal bleeding.
Understanding Battledore Placenta
- Battledore placenta refers to marginal insertion of the umbilical cord at the edge of the placenta, which is an anatomical variant rather than a pathological condition that causes maternal bleeding 1
- While battledore insertion can be associated with adverse fetal outcomes (such as intrauterine fetal demise when combined with other placental abnormalities), it does not cause the mother to experience vaginal bleeding 1
Actual Causes of Vaginal Bleeding in Pregnancy
The established causes of vaginal bleeding during pregnancy that should be evaluated include:
Second and Third Trimester Bleeding
- Placenta previa is the most common diagnosis in late pregnancy bleeding, affecting approximately 1 in 200 pregnancies at delivery, and requires ultrasound evaluation before any digital examination 2, 3
- Placental abruption affects approximately 1% of pregnancies and is the most common cause of serious vaginal bleeding, though ultrasound identifies at most 50% of cases 3, 4
- Vasa previa is rare but can result in fetal exsanguination and requires Doppler ultrasound for identification of vessels overlying the internal cervical os 2, 4
- Cervical lesions, polyps, or inflammation can cause vaginal spotting and are identified by speculum examination 3
First Trimester Bleeding
- Ectopic pregnancy must be excluded immediately as it can rapidly progress to life-threatening hemorrhage 3
- Subchorionic hemorrhage with viable pregnancy requires follow-up ultrasound in 1-2 weeks 3
- Threatened abortion or nonviable pregnancy requires serial beta-hCG monitoring 3
Critical Clinical Pitfall
Never perform digital vaginal examination until ultrasound has definitively excluded placenta previa, low-lying placenta, and vasa previa, as examination before imaging can precipitate catastrophic hemorrhage 2, 3. Transabdominal ultrasound is the preferred initial procedure for evaluating vaginal bleeding in pregnancy 2.
Clinical Context
While battledore insertion may be noted incidentally on ultrasound when evaluating vaginal bleeding, it is not the cause of the bleeding itself. The comprehensive ultrasound evaluation should assess placental location, the inferior placental margin, presence of clot, continuity of the myometrium, and any vessels overlying the internal cervical os to identify the actual source of bleeding 2.