Home Pregnancy Tests are now able to tell if you are pregnant about 10 days after conception - a week before your next period is even due, or your 24th day of pregnancy.
If you think you may be pregnant you should schedule an appointment with your OBGYN as soon as possible for a blood test and your first prenatal appointment (hint: take a list of questions with you). Plan on seeing your obstetrician about once a month through your first and second trimesters. Good health care is necessary for the development of your baby. You should avoid drugs (even many over the counter medicines!), alcohol, excess sugar, caffeine, and cigarettes - even second hand smoke can affect your unborn child (See Pregnancy No Nos for more information).
Your Baby
By the end of your fourth week your baby is an embryo. This group of embryonic cells is growing at a very rapid pace, each cell dividing daily. By the fourth week of pregnancy your developing baby is about 1mm in length and looks like a tiny tadpole, safely attached to your uterine wall and sending hormones to you body. The placenta is beginning to form and many wonderful and exciting changes are about to take place.Your Body
Your "next" period is due around the end of your fourth week of pregnancy. This occurrence, or lack thereof, is many times the first symptom of pregnancy. Some women may experience slight cramping or implantation bleeding when the blastocyst attaches itself to the uterine lining, but most of the changes taking place in your body are barely noticeable in these first few weeks.You should start adding calories to your diet. Depending on how much you weigh when you conceive, you should gain anywhere from 15 - 40 pounds during your pregnancy. To achieve this, a woman of average weight at the time of conception should eat around 2200 calories each day for the first 20 weeks, and then 2500 calories a day after that. Remember, you're supposed to gain weight, but be sure to make your calories count! You should eat healthy foods and get the right kind of exercise. You should also be sure to include folic acid into your daily diet, and ask your physician which prenatal vitamin is best for you.
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