First Trimester Vaginal Bleeding - Curbside
First Trimester Vaginal Bleeding
Editors: Casey Dart, Greg Wallingford, Phi Nguyen, & 7 more...
Inclusion Criteria  (All criteria are present)
  • History of current pregnancy (urine or serum)
  • <12 weeks gestation
  • History of any vaginal bleeding
Exclusion Criteria
  • History of complex GU/GYN surgery/coomorbidities
  • Obvious external cause of bleeding

Consider OBGYN consultation

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Total Notes: 8

1 Threatened miscarriage

Patients with threatened miscarriage should be managed expectantly. Close follow up with weekly transvaginal ultrasounds is necessary until a viable pregnancy is confirmed or excluded.

In patients where fetal cardiac activity is present at 7-11 weeks, 90-96% of pregnancies do no miscarry. These cases likely represent a disruption of decidual vessels at the maternal-fetal interface.

  1. Pregnancy outcome of threatened abortion with demonstrable fetal cardiac activity: a cohort study.
    Tongsong T, Srisomboon J, Wanapirak C, Sirichotiyakul S, Pongsatha S, Polsrisuthikul T,
    J Obstet Gynaecol (Tokyo 1995) 1995 Aug;21(4):331-5.
  2. Fetal loss in threatened abortion after embryonic/fetal heart activity.
    Tannirandorn Y, Sangsawang S, Manotaya S, Uerpairojkit B, Samritpradit P, Charoenvidhya D,
    Int J Gynaecol Obstet 2003 Jun;81(3):263-6.

2 First trimester bleeding

Vaginal bleeding occurs in up to 20-40% of women during their pregnancy. Miscarriage (threatened, inevitable, incomplete, complete) is the most common cause of bleeding occurring in 15-20% of pregnancies. Ectopic pregnancy is less common occurring in 2% of pregnancies. Although uncommon, ruptured ectopic pregnancy can be life threatening and should be always considered with vaginal bleeding in a pregnant woman. Other causes of bleeding include cervical, vaginal, or uterine pathology (eg. polyps, inflammation/infection, trophoblastic disease, etc.). In addition, women may have bleeding in early pregnancy from implantation.

  1. Expectant care versus surgical treatment for miscarriage.
    Nanda K, Lopez LM, Grimes DA, Peloggia A, Nanda G,
    Cochrane Database Syst Rev 2012(3):CD003518.

3 Physical activity precautions for threatened miscarriage

Limiting physical activity and sexual intercourse are often advised for patients with threatened miscarriages. However, randomized trials have found that bed rest at home or inpatient is not beneficial in preventing fetal lose. In addition, there are no studies showing abstinence from sexual intercourse decreases the likelihood of fetal loss. It is unclear if extreme physical activity is a risk factor.

  1. Bed rest during pregnancy for preventing miscarriage.
    Aleman A, Althabe F, Belizán J, Bergel E,
    Cochrane Database Syst Rev 2005(2):CD003576.

4 Progestins for threatened miscarriage

Multiple small studies including several meta-analyses have looked at the use of progestins to reduce the risk of threatened miscarriage. Initial results appear promising with decreased rates of fetal loss and no signs of congenital anomalies or pregnancy-induced hypertension. However, due to the small amount of data this treatment is not widely in use at this time.

Other medications and herbal treatments have been studied, but have not been shown to be efficacious.

  1. Progestogen for treating threatened miscarriage.
    Wahabi HA, Fayed AA, Esmaeil SA, Al Zeidan RA,
    Cochrane Database Syst Rev 2011(12):CD005943.
  2. A systematic review of dydrogesterone for the treatment of threatened miscarriage.
    Carp H,
    Gynecol. Endocrinol. 2012 Dec;28(12):983-90.
  3. Human chorionic gonadotrophin for threatened miscarriage.
    Devaseelan P, Fogarty PP, Regan L,
    Cochrane Database Syst Rev 2010(5):CD007422.
  4. Uterine muscle relaxant drugs for threatened miscarriage.
    Lede R, Duley L,
    Cochrane Database Syst Rev 2005(3):CD002857.
  5. Chinese herbal medicines for threatened miscarriage.
    Li L, Dou L, Leung PC, Wang CC,
    Cochrane Database Syst Rev 2012(5):CD008510.

5 Subchorionic hematoma

Subchorionic hemorrhages are common findings on transvaginal ultrasound. These hemorrhages are a risk factor for spontaneous abortion (OR 2.18), especially when the hemorrhage is 25% or more of the volume of the gestational sac. They are also a risk factor for placental abruption (OR 5.71) and preterm premature rupture of membranes (OR 1.64). Although emphasis is often put on size, location is likely to be more important (with worse outcomes with retoplacental hematomas)

Management for all subchorionic hematomas is expectant. Bed rest does not appear to decrease the risk of fetal loss. Presence of a hematoma is NOT an indication to begin a workup for thrombophilia.

  1. Subchorionic hematoma: a review.
    Pearlstone M, Baxi L,
    Obstet Gynecol Surv 1993 Feb;48(2):65-8.
  2. Perinatal outcomes in women with subchorionic hematoma: a systematic review and meta-analysis.
    Tuuli MG, Norman SM, Odibo AO, Macones GA, Cahill AG,
    Obstet Gynecol 2011 May;117(5):1205-12.
  3. Subchorionic hemorrhage in first-trimester pregnancies: prediction of pregnancy outcome with sonography.
    Bennett GL, Bromley B, Lieberman E, Benacerraf BR,
    Radiology 1996 Sep;200(3):803-6.

6 Rh(D) alloimmunization in pregnancy

If a Rhesus (Rh) D-negative pregnant woman is exposed to fetal D-positive red cells they are at risk for developing anti-D antibodies. If a mother has developed these antibodies from previous pregnancies then their Rh(D) positive fetuses/neonates  are at risk of developing hemolytic disease of the fetus and newborn, which can be associated with serious morbidity or mortality.

To prevent Rh(D) alloimmunization, RH positive women are given anti-D immunoglobulin whenever they are at risk of exposing their fetus (eg. vaginal bleeding). Anti-D immunoglobulin is produced from pooled plasma with high titers of IgG antibodies to D-positive erythrocytes.

  1. Neonatal hyperbilirubinemia and Rhesus disease of the newborn: incidence and impairment estimates for 2010 at regional and global levels.
    Bhutani VK, Zipursky A, Blencowe H, Khanna R, Sgro M, Ebbesen F, Bell J, Mori R, Slusher TM, Fahmy N, Paul VK, Du L, Okolo AA, de Almeida MF, Olusanya BO, Kumar P, Cousens S, Lawn JE,
    Pediatr. Res. 2013 Dec;74 Suppl 1:86-100.
  2. New laboratory procedures and Rh blood type changes in a pregnant woman.
    Sandler SG, Li W, Langeberg A, Landy HJ,
    Obstet Gynecol 2012 Feb;119(2 Pt 2):426-8.
  3. On the immunologic basis of Rh immune globulin (anti-D) prophylaxis.
    Kumpel BM,
    Transfusion 2006 Sep;46(9):1652-6.
  4. Rozrolimupab, symphobodies against rhesus D, for the potential prevention of hemolytic disease of the newborn and the treatment of idiopathic thrombocytopenic purpura.
    Stasi R,
    Curr. Opin. Mol. Ther. 2010 Dec;12(6):734-40.
  5. Rozrolimupab, a mixture of 25 recombinant human monoclonal RhD antibodies, in the treatment of primary immune thrombocytopenia.
    Robak T, Windyga J, Trelinski J, von Depka Prondzinski M, Giagounidis A, Doyen C, Janssens A, Alvarez-Román MT, Jarque I, Loscertales J, Rus GP, Hellmann A, Jędrzejczak WW, Kuliczkowski K, Golubovic LM, Celeketic D, Cucuianu A, Gheorghita E, Lazaroiu M, Shpilberg O, Attias D, Karyagina E, Svetlana K, Vilchevska K, Cooper N, Talks K, Prabhu M, Sripada P, Bharadwaj TP, Nćsted H, Skartved NJ, Frandsen TP, Flensburg MF, Andersen PS, Petersen J,
    Blood 2012 Nov;120(18):3670-6.
  6. On the mechanism of tolerance to the Rh D antigen mediated by passive anti-D (Rh D prophylaxis).
    Kumpel BM,
    Immunol. Lett. 2002 Jun;82(1-2):67-73.
  7. Controversies in Rh prophylaxis. Who needs Rh immune globulin and when should it be given?
    Bowman JM,
    Am. J. Obstet. Gynecol. 1985 Feb;151(3):289-94.
  8. The prevention of Rh immunization.
    Bowman JM,
    Transfus Med Rev 1988 Sep;2(3):129-50.
  9. One single dose of 200 microg of antenatal RhIG halves the risk of anti-D immunization and hemolytic disease of the fetus and newborn in the next pregnancy.
    Koelewijn JM, de Haas M, Vrijkotte TG, Bonsel GJ, van der Schoot CE,
    Transfusion 2008 Aug;48(8):1721-9.
  10. [Ante-partum administration of preventive treatment of Rh-D immunization in rhesus-negative women. Parallel evaluation of transplacental passage of fetal blood cells. Results of a multicenter study carried out in the Paris region].
    Huchet J, Dallemagne S, Huchet C, Brossard Y, Larsen M, Parnet-Mathieu F,
    J Gynecol Obstet Biol Reprod (Paris) 1987;16(1):101-11.
  11. Anti-D administration after childbirth for preventing Rhesus alloimmunisation.
    Crowther C, Middleton P,
    Cochrane Database Syst Rev 2000(2):CD000021.
  12. Anti-D administration in pregnancy for preventing Rhesus alloimmunisation.
    McBain RD, Crowther CA, Middleton P,
    Cochrane Database Syst Rev 2015(9):CD000020.

7 Transvaginal pelvic ultrasound

Transvaginal pelvic ultrasound is key for the evaluation of women in the first trimester who present with vaginal bleeding. The purpose of this test is to determine if the pregnancy is intrauterine or extrauterine (ectopic) and, if the pregnancy is viable (fetal cardiac activity - typically first detected at 5.5 to 6 weeks) or nonviable.

To define a failed pregnancy, the criteria use are based upon the development of a yolk sac or embryo once the gestational sac has reached ≥25 mm MSD. Other important components evaluated by the ultrasound include:

  • Fetal cardiac activity (lack of fetal cardiac activity when CRL of >5 to 6 mm has a sensitivity of 100% for failed pregnancy)
  • Fetal heart rate (if below 100 bpm at 6 to 7 weeks of gestation, increased risk of future failed pregnancy)
  • Growth rate
  • Abnormal gestational sac (increased risk of future failed pregnancy)
  • Abnormal yolk sac increased risk of future failed pregnancy)

  1. Sonography in first trimester bleeding.
    Dighe M, Cuevas C, Moshiri M, Dubinsky T, Dogra VS,
    J Clin Ultrasound;36(6):352-66.
  2. Transvaginal ultrasound in threatened abortions with empty gestational sacs.
    Tongsong T, Wanapirak C, Srisomboon J, Sirichotiyakul S, Polsrisuthikul T, Pongsatha S,
    Int J Gynaecol Obstet 1994 Sep;46(3):297-301.
  3. Limitations of current definitions of miscarriage using mean gestational sac diameter and crown-rump length measurements: a multicenter observational study.
    Abdallah Y, Daemen A, Kirk E, Pexsters A, Naji O, Stalder C, Gould D, Ahmed S, Guha S, Syed S, Bottomley C, Timmerman D, Bourne T,
    Ultrasound Obstet Gynecol 2011 Nov;38(5):497-502.
  4. Accuracy of first-trimester ultrasound in the diagnosis of early embryonic demise: a systematic review.
    Jeve Y, Rana R, Bhide A, Thangaratinam S,
    Ultrasound Obstet Gynecol 2011 Nov;38(5):489-96.
  5. When is a pregnancy nonviable and what criteria should be used to define miscarriage?
    Bourne T, Bottomley C,
    Fertil. Steril. 2012 Nov;98(5):1091-6.
  6. ACR appropriateness Criteria® first trimester bleeding.
    Lane BF, Wong-You-Cheong JJ, Javitt MC, Glanc P, Brown DL, Dubinsky T, Harisinghani MG, Harris RD, Khati NJ, Mitchell DG, Pandharipande PV, Pannu HK, Podrasky AE, Shipp TD, Siegel CL, Simpson L, Wall DJ, Zelop CM, Zelop CM,
    Ultrasound Q 2013 Jun;29(2):91-6.
  7. Early transvaginal ultrasound following an accurately dated pregnancy: the importance of finding a yolk sac or fetal heart motion.
    Deaton JL, Honoré GM, Huffman CS, Bauguess P,
    Hum. Reprod. 1997 Dec;12(12):2820-3.
  8. Pregnancy outcome following ultrasound-detected fetal cardiac activity in women with a history of multiple spontaneous abortions.
    Laufer MR, Ecker JL, Hill JA,
    J. Soc. Gynecol. Investig.;1(2):138-42.
  9. Gestational sac and embryonic growth are not useful as criteria to define miscarriage: a multicenter observational study.
    Abdallah Y, Daemen A, Guha S, Syed S, Naji O, Pexsters A, Kirk E, Stalder C, Gould D, Ahmed S, Bottomley C, Timmerman D, Bourne T,
    Ultrasound Obstet Gynecol 2011 Nov;38(5):503-9.
  10. Sonography of pregnancies with first-trimester bleeding and a viable embryo: a study of prognostic indicators by logistic regression analysis.
    Falco P, Milano V, Pilu G, David C, Grisolia G, Rizzo N, Bovicelli L,
    Ultrasound Obstet Gynecol 1996 Mar;7(3):165-9.
  11. Small sac size in the first trimester: a predictor of poor fetal outcome.
    Bromley B, Harlow BL, Laboda LA, Benacerraf BR,
    Radiology 1991 Feb;178(2):375-7.
  12. First-trimester, three-dimensional transvaginal ultrasound volumetry in normal pregnancies and spontaneous miscarriages.
    Acharya G, Morgan H,
    Ultrasound Obstet Gynecol 2002 Jun;19(6):575-9.
  13. Yolk sac size and shape as predictors of poor pregnancy outcome.
    Küçük T, Duru NK, Yenen MC, Dede M, Ergün A, Baser I,
    J Perinat Med 1999;27(4):316-20.
  14. Long-term prognosis of pregnancies complicated by slow embryonic heart rates in the early first trimester.
    Doubilet PM, Benson CB, Chow JS,
    J Ultrasound Med 1999 Aug;18(8):537-41.
  15. Outcome of first-trimester pregnancies with slow embryonic heart rate at 6-7 weeks gestation and normal heart rate by 8 weeks at US.
    Doubilet PM, Benson CB,
    Radiology 2005 Aug;236(2):643-6.

8 hCG measurement

A single hCG is not definitive for interpretation of the viability of a pregnancy. A widely accepted norm is that a gestational sac should be seen once the hCG has reached 1500 IU/L, however recent studies have shown wide variability in these measures. For instance, even in patients whose hCG reaches 2,000-3,000 mIU/mL, there will be 19 ectopic pregnancies and 38 nonviable pregnancies for every viable pregnancy. However, as many as 2% of women can still have viable pregnancies. Therefore, hCG levels must be used in serial measurements, usually 48 hours apart.

In general (but not always)

  • Falling hCG concentrations are consistent with a nonviable intrauterine pregnancy or involuting ectopic pregnancy
  • Rising hCG levels are most consistent with a viable intrauterine pregnancy or ectopic pregnancy
  • Plateaued hCG levels or levels rising very slowly are most consistent with an ectopic pregnancy or an abnormal intrauterine pregnancy

  1. Reevaluation of discriminatory and threshold levels for serum ß-hCG in early pregnancy.
    Connolly A, Ryan DH, Stuebe AM, Wolfe HM,
    Obstet Gynecol 2013 Jan;121(1):65-70.
  2. Diagnostic criteria for nonviable pregnancy early in the first trimester.
    Doubilet PM, Benson CB, Bourne T, Blaivas M, Blaivas M, Barnhart KT, Benacerraf BR, Brown DL, Filly RA, Fox JC, Goldstein SR, Kendall JL, Lyons EA, Porter MB, Pretorius DH, Timor-Tritsch IE,
    N. Engl. J. Med. 2013 Oct;369(15):1443-51.
  3. Clinical practice. Ectopic pregnancy.
    Barnhart KT,
    N. Engl. J. Med. 2009 Jul;361(4):379-87.
  4. Performance of human chorionic gonadotropin curves in women at risk for ectopic pregnancy: exceptions to the rules.
    Morse CB, Sammel MD, Shaunik A, Allen-Taylor L, Oberfoell NL, Takacs P, Chung K, Barnhart KT,
    Fertil. Steril. 2012 Jan;97(1):101-6.e2.
  5. Human chorionic gonadotropin profile for women with ectopic pregnancy.
    Silva C, Sammel MD, Zhou L, Gracia C, Hummel AC, Barnhart K,
    Obstet Gynecol 2006 Mar;107(3):605-10.
  6. What serial hCG can tell you, and cannot tell you, about an early pregnancy.
    Seeber BE,
    Fertil. Steril. 2012 Nov;98(5):1074-7.