Some 25% of all recognised pregnancies are complicated by bleeding, but only 15% miscarry (Everett 1987).
This is one of the commoner presentation to my clinic besides the general antenatal visit. The usual symptom is vaginal bleeding, which can be only brownish discharge to fresh red bleeding. Currently, there is no effective predictive test to differentiate possibility of a miscarriage from a continuing pregnancy in women with early pregnancy bleeding.
The biochemical(blood) tests, mainly pregnancy hormones include estradiol, human chorionic gonadotropin (HCG) and progesterone have not been used in clinic to predict the prognosis of this complication. A ‘doubling effect’ of serum HCG level over 48 hours denotes fetal viability at the time of testing but not useful to determine outcome. Not long ago, the serum progesterone level showed some potential in prognostication of early pregnancy bleeding. (Please see Medical News Update on further discussion of serum progesterone)
It is important to locate the cause of vaginal bleeding to ascertain if the bleeding originates from the uterus (conceptus) or outside the uterus (cervix or vagina).
Some of the common causes of vaginal bleeding in early pregnancy include:
1. Miscarriage- usually perigestational hemorrhage
2. Molar pregnancy
3. Ectopic pregnancy
4. Cervical polyp
5. Cervical erosion
6. Cervical malignancy
7. Vaginal wound
An ultrasound assessment of the pregnancy is warranted and this includes a transvaginal ultrasound. I usually attempt to identify the following features:
1. Site of pregnancy
2. The shape/ margin of the gestational sac
3. Presence of the yolk sac/fetal mass/ fetal heartbeat
4. Presence of any peri-gestational hemorrhage (PGH)
While feature 2) and 3) are usually reassuring, the presence of a large PGH is associated with a poorer outcome. The demonstration of fetal heartbeat on ultrasound scan has been shown to reduce the risk of miscarriage to 2 percent only (Cashner 1987; MacKenzie 1988).