But it usually takes 3 to 4 weeks for levels of hcg to be high enough to be detected by home pregnancy tests. The brain, spinal cord, heart, and other organs are beginning to form. Take a journey with us from the moment a single sperm fertilizes an egg. (2) claude edelmann / photo researchers, inc.
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Moving into the fallopian tube
This is called a tubal pregnancy or ectopic pregnancy and is a danger to the mother. The cells keep dividing. From tiny egg to growing embryo, follow the incredible process of conception.