Can someone who is pregnant

Stefanie • Fri, Jan 02 • I`m 28 years old and happily married and have 4 children. 3 girls and a newborn boy!

At least 10 weeks pregnant or more, pee on an ovulation test and see if comes back positive? I have one person saying that OPKs only show up around 4 weeks pregnant and I'm curious if OPKs really show positive throughout pregnancy or just in the first trimester. Thanks!