The zygote begins to develop rapidly within a day after it is fertilized. In three days, a cluster of cells (morula) will exit the Fallopian tube and enter the uterus. Then a fluid-filled cavity will form as the morula grows. The fertilized egg -- now called a blastocyst -- starts dividing into hundreds of cells by the eighth day of post-fertilization. Once safely in the uterus, it embeds itself, adhering tightly to the top of the uterine lining.
Pregnancy -- in all its accompanying signs, symptoms, and surprises -- is different for every woman, especially in the first trimester. Some women feel physically out of sorts, while others experience emotional upsets (as if they were premenstrual). For the more fortunate, the only sign of having conceived is the absence of menstruation.
So if you think you may be pregnant, be on the lookout for any or all of these telltale signs: tender, swollen breasts; nausea; queasiness; increased urination; tiredness; cravings for certain foods; and darkening of the skin around the nipples (areolas).
On the emotional end, you may feel weepy, unstable, irrational, and all-around irritable. If you're more prone to mood swings, you may feel joy and elation on a good day and, on a less-than-cheery one, misgivings or fear. These feelings may set in as early as the first month of pregnancy, or they may develop sometime in the second. If you're really lucky, they may not affect you at all.
Note: If you have any bleeding, pelvic pain, non-stop vomiting (unable to even tolerate liquids), painful urination, or sudden swelling of your hands, feet, or face, you should call your doctor immediately.
Planning on being pregnant or hoping you already are? If so, you need to eat accordingly. That means getting the proper amount of the correct foods. To see what your nutrition needs are during the next nine months, check out the food pyramid.
If you're trying to conceive or think you may be pregnant, you should start taking a prenatal vitamin ASAP, or at least 3 months before you plan to conceive. Choose a vitamin with at least 400 mcg of folic acid, a B vitamin that’s been shown to reduce the risk of severe birth defects.
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