The original song was "One is the Loneliest Number" by Three Dog Night but I've found that being one plus a baby growing inside can be even lonelier.
First, whoever is adding to the culture that you should wait until the end of your first trimester to tell people you are expecting needs to butt out. I'm guessing you haven't been pregnant or you clearly told people in secret.
It's not about the excitement of the news (which yes, can be very exciting), it's about a huge transition in your life that you DO NOT want to rely on Google, chat rooms, and books by authors you've never heard of previously to guide you in. I'm a firm believer in reaching out quickly to those you trust, like in the first week of knowing if you can! I'm not talking about a facebook reveal here, these are also the people you'd lean on in events like heartache, bad days or something worse.
All the feelings you've ever had and never knew could exsist will start brewing inside you before you fall sleep the first night. You don't need to hold on to those emotions so tight because what could be tears of joy one night could be something much darker and 'lonelier' another.
From the beginning of pregnancy (and beyond) always do/say/share what feels right to you. If you feel like you're holding too much in and feel the weight of pregnancy before the pounds even start to accumulate, then god dammit lean on someone.
And if it's a day you want to scream "I HATE BEING PREGNANT" email or text me just that. I will know that yes, you still love your baby, and that just typing it made you feel better without even needing to respond.