While there's no guaranteed "right time" to share your big news, you can increase your chances of meeting with a positive response if you plan your announcement carefully. Here are a few tips:

Anticipate your employer's concerns and be prepared to address them. Go in with a game plan that specifies how long you intend to be off work, who might be able to replace you, and what you intend to do to help train your replacement. Of course, you'll want to make it clear that this is just a game plan -- not a guaranteed blueprint for the months ahead. Circumstances may change if you run into some unexpected complications with your pregnancy, notes Hamilton, Ontario, obstetrician Margaret Lightheart, MD.

Understand your rights as a pregnant employee. If you are expecting a performance or salary review in the near future, keep your news to yourself for now. That way, if the review doesn't go as well as you had hoped, you won't have to wonder whether you're the victim of pregnancy discrimination.

Time your announcement to coincide with a major achievement at work (i.e. the completion of a major project). That way, you can show your boss through actions rather than words that you are as productive and committed to your job as ever, thereby addressing a perennial fear of many employers.

If you think your boss will react negatively to your news, wait until the highest-risk period for miscarriage has passed before sharing your news. (Of course, if you are suffering from severe morning sickness or other pregnancy-related complications, you may have to spill the beans a little sooner than you had hoped in order to explain why you are late coming in each morning or why you have been taking so much time off for medical appointments.)

Don't be afraid to postpone your announcement if your boss is having a particularly bad day. If she is in a foul mood or is scrambling to meet an important deadline, hold off on sharing your news until she's in a more receptive frame of mind.

Last but not least, be prepared for a less-than-enthusiastic reaction. While your boss may be genuinely happy for you, she may be concerned about what your pregnancy may mean to her and the company, particularly if this is her first experience of dealing with a pregnant employee. Still, don't let her concerns about how your pregnancy is going to impact the company's bottom line make you feel guilty. No one has the right to rain on your parade during this wondrous time in your life.

About the author: Ann Douglas is a bestselling pregnancy and parenting author and mother of four. Her latest books are Sleep Solutions for Your Baby, Toddler, and Preschooler: The Ultimate No-Worry Approach for Each Age and Stage and Mealtime Solutions for Your Baby, Toddler, and Preschooler: The Ultimate No-Worry Approach for Each Age and Stage. You can find her online at www.having-a-baby.com.