Week 1

Mom & Baby:

When exactly pregnancy starts is one of those things that often puzzles first-time parents. It may seem strange, but doctors count Day 1 of your last menstrual period before conception as Day 1 of your pregnancy.

So at this point you aren't actually pregnant yet, but it's never too early to act as if you are: eating healthy food, getting a full night's sleep, not drinking alcohol and not smoking.

If you've been following these healthy guidelines, great! If not, don't worry — just remember to take care of yourself. And pass along the good habits: This advice is important for your partner, too.

What’s Happening Inside You:

Incredibly, millions of eggs developed in your ovaries while you yourself were still in utero (though that number was reduced dramatically shortly before your birth). During each menstrual period, your body produces an egg and your uterus lining thickens to provide the best possible circumstances for a fertilized egg to attach itself and start growing.

If your egg (or eggs) is not fertilized during any given month, the uterus sheds its lining — thus your menstrual period. As soon as your period is over, several new eggs are developed in one or both of your ovaries.

It’s a good idea to see your gynecologist for your annual exam and a pap smear before trying to get pregnant. You should also consider getting certain vaccinations pre-conception, like chicken pox (if you haven’t had the disease) and Tdap, which can help protect a newborn against whooping cough.

Also make sure you are regularly taking a multivitamin that includes folic acid (up to 1 gram per day).

An egg is a woman’s largest cell, and a sperm cell (or spermatozoon) is a man’s smallest cell.

Find out more about your cycle and the best time to get pregnant.