Pregnancy Test Dates and Early Ultrasound Don't Match

Cynthia Flynn's picture
Experts: 

QUESTION

My last period was January 10th. On February 20th I finally got a positive pregnancy test after having nausea, breast tenderness and mild cramping for two weeks.

I saw my family doctor for my yearly physical on February 9th, at that time my uterus was normal sized. On February 23rd my doctor sent me for blood work and all came back looking good. With my son (now 5.5 years old) I did not get a positive urine pregnancy test until I was almost 6 weeks and had seen the yolk sack on an early u/s. He also always showed small for date on any u/s I had.

On February 28th I had some pink spotting that went away. The next day the spotting continued and cramping started. I stayed in bed and rested hoping everything would stop. Wednesday morning the spotting had stopped but not the cramping. I went to the doctor and he ordered an early u/s. I had the u/s the same day but there was no heartbeat or fetal pole, there was a sack present. The u/s technician and radiologist thought that I might be 4 weeks pregnant. That would mean that I had the positive pregnancy test about 2.4-3 weeks pregnant. I do not think that is even possible.

I thought I was 7 weeks pregnant. I can understand my ovulating later then thought, I have a history of PCOS and endometriosis. I am just really confused about what my body is doing right now. I am afraid that I have lost the baby and I really want a baby. I am 41 and had decided that this pregnancy is it. I can not go through the stress of wanting to be pregnant and not getting there again. It has taken five years for this pregnancy and my son so wants to be a big brother.

My doctor will be ordering serial HCG tests and probably another u/s in a couple of weeks assuming the HCG results are good.

Is it possible not to see a heartbeat at 6-7 weeks?

Thanks.

ANSWER

Some people do make hcg very quickly (especially if they have twins!), so yes, you are right that it is unlikely, but it IS possible to have a positive pregnancy test when you are three weeks pregnant (i.e. one week after conception), which is what those tests that say they can you that you are pregnant five days before your period is due are counting on.

It sounds like the management plan is appropriate. Between the serial hcg's and the next ultrasound, you should end up with a pretty good idea about whether the pregnancy is viable and how far along you are.

Good luck!
~Cynthia