Recommend

Features pregnancy:

http://www.mangago.me/read-manga/keeper_of_the_pearl/
http://www.mangago.me/read-manga/kiraide_isasete/
http://www.mangago.me/read-manga/blood_link/ (not exactly omegaverse but, really similar and has mpreg)

No shown pregnancy but, omegaverse couple with a kid:

http://www.mangago.me/read-manga/tadaima_okaeri/
http://www.mangago.me/read-manga/hyacinth/
http://www.mangago.me/read-manga/ouchi_e_kaerou_neko_mimi_omegaverse/
http://www.mangago.me/read-manga/kekkon_shite_kudasai/

Hope I helped!! Have a great day!!!