mm dunno hun! looks on google....
and found this:
The gestational sac is the earliest sonographic finding in pregnancy. The gestational sac appears as an echogenic (bright echoes) ring surrounding a sonolucent (clear) center. The gestational sac does not correspond to specific anatomic structures, but is an ultrasonic finding characteristic of early pregnancy. Ectopic pregnancies can also have a gestational sac identified with ultrasound, even though the pregnancy is not within the endometrial cavity.
The gestational sac first appears at about 4 weeks gestational age, and grows at a rate of about 1 mm a day through the 9th week of pregnancy.
Your ability to identify an early gestational sac will depend on many factors, including the capabilities of the ultrasound equipment, your approach (vaginal or abdominal), your experience, the orientation of the uterus (generally it is easier to see if the uterus is anteflexed or retroflexed), and the presence of such complicating factors as fibroid tumors of the uterus. While a gestational sac is sometimes seen as early as during the 4th week of gestation, it may not be seen until the end of the 5th week, when the serum HCG levels have risen to 1000-1500 mIU.
So yes maybe! but still might be a bit to early!
but know i would wait for few days after missed af to test!! im just not a poas addict.. geez whats wrong with me 
is due since it is my first month of bcp. Good luck to everyone! 
(with an ultrasound probe)
