Do some pregnant women not give out enough hormoes for a pregnancy test to read positive in the first trimester?

No, all pregnant women produce enough hormones for a pregnancy test to read positive in the first trimester. Pregnancy tests detect the presence of human chorionic gonadotropin (hCG), a hormone produced by the developing placenta after implantation of a fertilized egg. As early as 6-10 days after conception, hCG levels begin to rise rapidly in a pregnant woman's body, and they continue to increase throughout the first trimester. By the time most women miss their period and realize they might be pregnant, hCG levels are usually high enough to be detected by a pregnancy test