How would you recommend I tell my work that I am pregnant?

In the U.S., the general recommendation is that you inform your immediate supervisor when you are about 3 months along, not before.  Then, when you are closer to your due date, you discuss what will happen.  They are still required to meet FMLA laws.  Your employer can choose to hire a temporary replacement or cross-train other employees.

You and your Ob/Gyn will discuss when you should take off work before the baby is due (or you might work until you go into labor -- your choice).  Then you will need to take some time off to recover.  How much time will depend on the birth and your preferences.  If you take off longer than required by law, your employer can still choose to hold your job and use a temporary employee.  They can also choose to hire someone permanently.

As others have noted, you also can choose to look for work elsewhere after the baby is born and you are ready to return to work.  

Why tell (given your thoughts) ? They will figure it out when you start to show. It is NOT your job to solve their staffing problems, and they cannot fire you for being pregnant.

That field is easy to find other jobs in and probably higher paying jobs. If they don't understand and aren't compassionate enough to give you time off for maternity they're not worth working for if they're that inconsiderate and careless when it comes to human nature. You're not a mechanical machine you are human.

The right thing to do is tell them in enough time so they are informed at least. You're taking maternity time off whether they approve of it or like it or not. You absolutely need time off to at least recover. You should have / take several weeks off to be with the baby as much as you can the first few weeks.

They'll just have to deal witth it and either hire you another agent for your office so it's covered during your maternity, let you hire someone, do without you until you feel you can come back to work, or lose you and not have any thing at all get done while you're off that they don't do them selves.

Be prepared. If they're incompassionate, greedy, ******* like I've experienced some managers to be (I've had managers try and fail to not allow me to come home when my mother died for her final services), be prepared. They're either going to think they can continue to manipulate you like you're their little robotic machine that does whatever they say and makes them money and get a rude awakening or they're going to fire you.

So, first, get a new job lined up.

The more time they have, the more easily they can prepare for your absence...

If you are in the USA, they are required to give you the time off as required by state and federal law. If you need more time than that, they may or may not be required to comply. Is your employer subject to FMLA?

If you quit before returning from your leave, your medical insurance may be cancelled retroactively depending on the circumstances/law where you are.

I suggest you sit down with your employer like a mature adult, tell them what your plans are, what your time frame is and then work out a solution that works for both of you.

Look dear they own the business not you. Don't give them a second thought about how they will manage, it's not your problem. The owner will have to get off their bum and work instead of spending the money you earn.

Hopefully you will be able to return at a later date.

There may be time off benefits that you aren't aware of. This will be based on where you are located and how many employees the company has.

The standard time off for a delivery is 6 weeks for a natural birth and 8 weeks for a c-section. But people in your shoes who do not have a paid income while you are off work might reduce that to 2-4 weeks. Only you can determine how to handle it.

It's the company's issues, not yours, that there is no one crossed trained in your position. Maybe it will make sense to outsource your role while you are off or to bring in a temp employee to handle the most important aspects while you are on LOA. It would be a good idea for you to formulate a plan so you have that to discuss with your employer when the time comes.

Based on your other questions, you appear very newly preggie. You should not tell your employer while you are in the first trimester. If you can continue to disguise it, you should wait to tell them until the 5th month.

You tell them the truth.

You are pregnant.

You will require time off.

You hope that they will keep your position open while you are gone.

You hope you can come back to them as you really enjoy working for them.

Do not apologize. And make sure they know that your health and your baby's health is of the upmost importance to you. And stick your ground. If they need to, they can refer to a temp agency to find someone to do your job for awhile. Or hire someone on contract.

Either way they need to know so they can make arrangements.