| ENCYCLOPEDIA INDEX |
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| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z |
First trimester pregnancy |
| Overview Symptoms Treatment Prevention |
| Definition: |
The first trimester of pregnancy begins when a fertilized egg implants into a woman's uterus. This occurs about 7 days after the egg is fertilized. The first trimester ends when the fetus is about 12 weeks old. (This is about 14 weeks from the first day of the last normal menstrual period.) |
| Alternative Names: |
| Early pregnancy; Pregnant - first trimester |
| Causes, incidence, and risk factors: |
Pregnancy is a normal condition and, in most situations, should not be approached as a problem or disease. Any fertile female engaged in a sexual relationship with a fertile male is at risk of becoming pregnant. |
 Ultrasound in pregnancy |  First trimester of pregnancy |  Miscarriage |  Early weeks of pregnancy |
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