Polycystic ovary syndrome (PCOS) is one of the most common gynaecological endocrine diseases in women and the main cause of anovulatory infertility. Compared with women with normal ovulation, PCOS patients are more likely to face ovarian hyperstimulation syndrome, poor-quality of oocyte and fertilization failure in assisted reproduction treatment, so ovulation induction in PCOS patients has attracted much attention in the reproductive field. Progestin-primed ovarian stimulation (PPOS) protocol uses exogenous progesterone effectively to block luteinizing hormone surge to achieve ideal number of retrieved oocytes, embryo quality and pregnancy outcomes. This article reviews the mechanism, clinical application and development of PPOS protocol in PCOS patients.

Polycystic ovary syndrome (PCOS) is one of the most common gynaecological endocrine diseases in women and the main cause of anovulatory infertility. Compared with women with normal ovulation, PCOS patients are more likely to face ovarian hyperstimulation syndrome, poor-quality of oocyte and fertilization failure in assisted reproduction treatment, so ovulation induction in PCOS patients has attracted much attention in the reproductive field. Progestin-primed ovarian stimulation (PPOS) protocol uses exogenous progesterone effectively to block luteinizing hormone surge to achieve ideal number of retrieved oocytes, embryo quality and pregnancy outcomes. This article reviews the mechanism, clinical application and development of PPOS protocol in PCOS patients.

To investigate the clinical diagnostic value of ultrasonographic superb micro‐vascular imaging ( SM I) for abdominal branch arteries′involvement in Stanford B aortic dissection ( AD ) . Methods A total of 34 AD patients underwent conventional ultrasound ,SMI and CTA . The characteristics of the ultrasonographic images of branch artery involvement including coeliac artery ,superior mesenteric artery ,left and right renal artery were analyzed . T he diagnostic performance of conventional ultrasound and SM I were compared and CT A was used as the reference standard . Results Among the 34 patients with AD ,according to the ultrasonographic images′characteristics ,136 branch arteries were categorized into four classes :Class Ⅰ (81/136) ,branch artery perfusion supplied from the aortic true lumen ; Class Ⅱ ( 27/136) , dissection extending into the branch ; Class Ⅲ ( 16/136 ) ,branch artery perfusion supplied from the aortic false lumen ; Class Ⅳ ( 12/136) ,branch artery perfusion supplied from the aortic true and false lumens . T he diagnostic accordance rate of the conventional ultrasound and SM I were 76 .5% ( 104/136 ) and 92 .6%( 126/136) and had significant differences ( P ＜0 .001) . Conclusions SMI can be used to evaluate branch artery involvement in AD patients w hich will guide the practice of pre‐operation and post‐operation .