The Emperor Has No Heirs? I Keep Getting Pregnant and Rule the Harem

[Satisfying rebirth story + devoted love in the later chapters + clear-headed heroine throughout] In her previous life, Su Yue was blessed with exceptional fertility, but her half-sister plotted against her, had her tongue cut out, and imprisoned her for seven years, turning her into a surrogate for her sister. Her three sons became stepping-stones for Su Yao to ascend to the throne as empress, while her swaddled baby girl was turned into a secret fertility potion. Su Yue died in despair at Su Yao's hands, never escaping the underground chamber where she'd been imprisoned for seven years. Reborn, Su Yue uses her gift for bearing children as bait to lure the emperor in. They say she's lowborn? Then she'll win his favor by bearing his children and take the empress's throne! Her half-sister wants to use her as a surrogate? Then she can hardly blame Su Yue for flaunting her imperial favor and using her belly to put people in their place! Su Yue plots every step and keeps everything under control. The four children she lost in her previous life are born one after another: her eldest son becomes crown prince, her second son commands the army, her third son manages court affairs, and her youngest daughter is blessed by fate and saves the people... Even the emperor, who once cared only about heirs, becomes obsessed with her, blocking her bedside night after night. “Yueyue, who matters more, those little brats or me?” “But Your Majesty said we had to fill the palace with heirs and strengthen the imperial house.” “No more children! If we have another, I'll lose your favor!”