I'm going to go through this as delicately as possible.
The PoJ says this about Jesus' birth:
2 And they stood in the place of the cave: and behold a bright cloud overshadowing the cave. And the midwife said: My soul is magnified this day, because mine eyes have seen marvellous things: for salvation is born unto Israel. And immediately the cloud withdrew itself out of the cave, and a great light appeared in the cave so that our eyes could not endure it. And by little and little that light withdrew itself until the young child appeared: and it went and took the breast of its mother Mary.
According to the PoJ, there was no normal vaginal birth. There's a light that disappears and a child appears. It goes to her breast. There were two consequences. One Mary evidently remained a virgin. Two she remained in the puerperal state. This does relate to birth, but specifically to things remaining in the uterous after birth.
Now Clement of Alexandria who is commenting on that "appearance", not normal birth:
"But, as appears, many even down to our own time regard Mary, on account of the birth of her child, as having been in the puerperal state, although she was not. "
SHE WAS NOT in the puerperal state. Why? She gave birth normally. The sign of virginity is gone. Out came water, baby, placenta, all of it. Mary wrapped Him in the swaddling clothes. Mary lifted Him to her breast. She was healthy; there was no delayed uterine infection-puerperal state. (The PoJ says there was a midwife in contradiction to Scripture.)
'For some say that, after she brought forth, she was found, when examined, to be a virgin.'
For/because/the reason some say she was in the puerperal state is some (PoJ) say after she brought forth, she was found to be a virgin. The puerperal state would be caused by that stuff remaining in the uterus (not coming out). And the stuff stayed there because they say she remained a virgin.
That's the reason. Clement of Alexandria denies it. She gave birth normally, all of it came out, she wrapped the Child, and fed Him herself.
With that in mind, he then says instead,
"Now such to us are the Scriptures of the Lord, which gave birth to the truth and continue virgin,"
That's the continuing virgin. Not Mary. It's the My Word is life, but I digress.