Assessment and treatment for those women who are less than 20 weeks gestation presenting to the ED with abdominal pain and/or vaginal bleeding may indicate a threatened miscarriage/spontaneous abortion.

PV bleeding and pain in early pregnancy is very common. In fact it is thought to happen in almost one in every four pregnancies.

Why does miscarriage occur?

Much is still unknown about why early miscarriage occurs . But the most common cause is believed to be a chromosome problem that occurs at fertilization. Miscarriage usually occurs in the first 12 weeks of the pregnancy.

What are the risk factors for having a miscarriage?

The risk of miscarriage is increased by:

  1. A women’s age
  2. The risk of early miscarriage increases with age. At the age of 30 the risk is 1 in 5 (20%). At the age of 42 the risk is 1 in 2 (50%).
  3. Pre-morbitities e.g. Diabetes, heart disease
  4. Life style factors e.g smoking and heavy drinking


About a third to half of all women who have bleeding in early pregnancy will go on to miscarry.

One cause for bleeding in early pregnancy is an “implantation bleed” This happens when the pregnancy implants itself into the lining of the uterus. The bleeding will often last a few days and then stop.

Complete Miscarriage: Spontaneous expulsion of products of conception, with resolution of symptoms.

Incomplete Miscarriage: Bleeding and cramping with products of conception visible in the uterine cavity.

Missed Miscarriage: Non-viable intact gestation sac within the uterus with delay to on wet of symptoms of miscarriage.

Blighted Ovum: Generally refers to a missed miscarriage in which embryonic development stopped before the embryonic pole was visible. The gestation sac may continue to grow.

Molar Pregnancy (hydatidiform mole): Affects only an estimated 1 in 1000 pregnancies. It is the fertilization of an empty ovum by a single sperm the chromosomes of which are duplicated.

Ectopic Pregnancy: This results when implantation of the conceptus occurs at a site other than the uterine cavity. It affects 1% of all pregnancies and almost all (about 98%) occur within the fallopian tubes. Other sites for an ectoptic pregnancy include the cervix, abdominal cavity and the ovary itself.

1 in 5 case the tube ruptures causing internal bleeding and shock. This is a medical emergency requiring immediate surgery and/or blood transfusion.


Quantitative beta- hCG Level: After conception hCG is detectable in maternal plasma after 7-8 days. Levels rise rapidly and in a healthy early pregnancy double every 48-72 hours. Maximum beta-hCG levels are obtained at about 10 weeks after which there is a gradual decline to 20 weeks at which time they stabilize.

Serial testing for miscarriage is most useful between 4-6 weeks when ultrasound is less helpful.

Full Blood Count

Urinalysis: Should be attended if the patient has pain without bleeding as a possible diagnosis could be cystitis/UTI/pyelonephritis.

Group and Hold: Cross match if unstable or actively bleeding. If patient is Rhesus (Rh) negative they will require an injection of anti-D immunoglobulin to prevent problems with the Rh factor in future pregnancies.

Ultrasound: With the continuously improving resolution obtained from modern ultrasound machines, ultrasound is increasingly able to answer the important questions raised when there is bleeding in early pregnancy

  1. What is the location of the pregnancy?
  2. What is the gestation of the pregnancy?
  3. Is a live embryo or fetus present (and if son how many)?
  4. Is any placental pathology apparent?

Ultrasound also has the advantage of providing the patient with immediate information, which in many situations (especially when the gestation is greater than 6 weeks) will be conclusive with a single examination. However if an intrauterine gestation is seen, but there is uncertainty about the viability of the pregnancy a repeat ultrasound in 7-10 days is most likely to be the most effective follow up.


Emergency Nurses should understand and be aware that women who presents with a miscarriage have worry and anxiety and are seeking reassurance that their pregnancy and baby are alright. A women’s response to miscarriage range from acceptance to disappointment or anguish and are often followed by an extended period of grieving. When these women become pregnant again it is like returning to the site of a past trauma where dreams were shattered. Unlike earlier pregnancies where excitement and anticipation were common, pregnancies that occur after a previous loss are characterized by anxiety and worry about another loss, comparisons with past pregnancies and holding back attachment to this pregnancy and baby.

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Royal Women’s Hospital Victoria