It is narrated from Hazrat Abu Saeed Khudri (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said regarding the captives of the Battle of Autas: No person should have intercourse with a pregnant slave woman until she gives birth, and if she is not pregnant, then he should not have intercourse with her until one or two menstrual cycles have passed.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 11823
Hadith Gradingحکم دارالسلام:حديث صحيح لغيره، وهذا إسناد ضعيف لضعف شريك