The uterus is gravity, no focial lesion noted. A regular walled gestational sac is noted in uterine cavity well placed in fundoposterior region with good trophoblatic reaction. No obivous calloection is seen around te sac. The yolk sac is seen but fetal pole is not yet visualized. The gestational sac (G-S mean sac diameter) is 4.5mm corresponding 4-5 weeks. Cervix is normal in length. The internal os is closed. No adnexal mass is seen. But I have pcos also...tell me why fetal pole is not visualized...