Vaginal bleeding in pregnancy (less than 20wks)

Background

1. Occurs in 20-40% of 1st trimester pregnancies
2. Once IUP is confirmed by ultrasound no utility in obtaining B-hCG
3. Ultrasound
   1. Do not use hCG to determine whether ultrasound should be obtained
      1. "Discrimatory Zone" values are for IUP visualization, not ectopic visualization
         1. Pelvic - can visualize IUP at hCG ~ >1500
         2. Abd - can visualize IUP at hCG ~ >6000

DDX

1. Ectopic Pregnancy
   1. hCG > 1500 + no IUP
2. Miscarriage
   1. Complete Abortion
      1. <12 weeks + no IUP
      2. Distinguish from ectopic based on decreasing hCG, decreased bleeding
         1. Only need to send hCG if unable to examine POC
   2. Threatened Abortion
      1. Closed os + IUP + cramps and/or bleeding
      2. If < 11wks >90% go to term
      3. If between 11 and 20 weeks 50% go to term
   3. Inevitable Abortion
      1. Open os + contractions/cramps
   4. Incomplete Abortion
      1. >12 wks + passage of only portion of POC
   5. Missed Abortion
      1. <20 wks + no cardiac activity
3. Non-pregnancy related bleeding
   1. Cancer
   2. Fibroids
   3. Cervicitis

Evaluation

1. History
   1. Previous spontaneous abortion?
   2. Extent of bleeding, clots, tissue
   3. Presence of cramping
   4. Light-headedness?
   5. Risk Factors for Ectopic
      1. PID
      2. IUD
      3. Adnexal surgery
2. Physical
   1. Uterus able to palpated in abdomen ~ 12 weeks
   2. Uterus able to visualzed by abdominal ultrasound ~ 10 weeks
   3. Open OS decreases, but does not rule-out, ectopic
   4. If find POC send to pathology to rule-out trophoblastic disease

Work-Up

1. B-hCG (quant)
2. CBC
3. T&S (Rh) vs. T&C
4. IVF vs. blood
5. UA
6. RhoGAM if indicated
7. Hemabate/Pitocin if indicated
8. Ultrasound
   1. IUP = Threatened AB
      1. Ectopic ruled-out unless on fertility drugs
   2. Empty uterus + free fluid/adnexal mass = Ectopic
   3. Empty uterus + no free fluid / no mass:
      1. BHC-G:
         1. >6,000 = Ectopic
         2. 1,000 - 1,500 = indeterminante (?D&C if undesired)
         3. <1,500 = follow serial B-HCG levels (x 48hrs)
            1. Increased >66% = nL IUP
            2. Increased < 66% = Ectopic

Source

UpToDate, Rosen's