QuestionI am 19dpo after an IUI. At 15 dpo I had what I assumed to be a period (bright red blood, some clumps). I had a beta HCG that morning and when I called the next day, i was told it was positive, but Low at 24. My progest was 0.7 ( I am on prometrium). They said to go back and get another test, which I did that night, 36 hours after the first. Again, it came back +, up to 35. So they had me do it again the next day, and it was up to 75. So, I have to go back again. I guess my question is, is this pregnancy possible? With a progest so low I would not think so, but my HCG levels keep rising!!
Any insight? They mentioned a tubal preg....
AnswerPeak HCG level % of ectopics
<1000
45%
1000-3000
21%
3000-5000
15%
5000-10,000
10%
> 10,000
9%
Trend of hCG titers with ectopic pregnancies
Trend of HCG levels
% of cases
Falling
57
Abnormally rising 36%
36
Normally rising 6.4%
6.4
General rules often used for hCG levels:
Tables with normal values for HCG levels in early pregnancy (single and twins listed).
The hCG level should rise at least 66% in 48 hours, and at least double in 72 hours.
Plateauing hCG levels with either a half-life of > or = 7 days or a doubling time of > or = 7 days have the highest predictive value for ectopic pregnancy of any hCG pattern.
An important point is that the lower limit in these "formulas" for hCG doubling times, etc., is usually the 15th percentile for symptomatic but viable pregnancies. Therefore, we have to be careful to give pregnancies with slow hCG rises every chance possible because they may turn out to be normal.
Progesterone levels and ectopics
Progesterone levels are usually not of much use in making the diagnosis of ectopic pregnancy, but they can be another clue.
A progesterone level of less than 15 ng/ml is seen in: 81% of ectopics, 93% of abnormal intrauterine pregnancies, 11% of normal intrauterine pregnancies.
Less than 2% of ectopics and less than or equal to 4% of abnormal intrauterine pregnancies will have a progesterone level greater than or equal to 25 ng/ml.
Therefore, a single progesterone value less than 15 is probably an abnormal pregnancy of some kind.
A single value over 25 is probably a normal pregnancy. If the woman had ovarian stimulation with medication this value may not be applicable.
Ultrasound and Ectopics
With good vaginal probe ultrasound (vag probe is best for imaging the uterus), a normal singleton pregnancy can be seen by the time the hCG level reaches 2000 mIU/ml.
By 5.5-6 weeks of pregnancy (1.5-2 weeks after the missed period) all normal pregnancies should be seen by vaginal ultrasound.
20-30% of ectopics have no detectable sonographic abnormality.
The usual finding for ectopic is a mass on one side, some fluid in the pelvis, and no normal pregnancy structures in the uterus.
Conclusive diagnosis of ectopic by ultrasound can only be made if fetus or fetal cardiac motion is seen outside the uterus. This is only seen in about 20% of ectopics with vaginal probe ultrasound.
Sac in uterus: A "pseudosac" is seen in 10-20% of ectopics. This is a sac in the uterus that is not a pregnancy but can look like one initially. We need to see a yolk sac, a fetal pole or cardiac motion to be sure it is a normal pregnancy.
