Fertilization

Pregnancy begins at fertilization, which is the uniting of the male sperm with the female egg.  During sexual intercourse, millions of sperm are ejaculated through the man’s penis into the woman’s vagina.  The sperm move through the opening of the cervix to the uterus and into the fallopian tubes, guided by cervical fluid (mucus).

Although extremely small, the new cell (zygote) formed by the union of a mother’s egg and a father’s sperm contains the blueprint for every detail of its development-sex, hair and eye color, height, etc  This is the first stage of human life.

Before tests can detect a pregnancy, the child is safely positioned in the mother’s uterus for nurturing.  For the child, this time in the uterus is marked by rapid growth and change.

Not long ago, the nine months of a child’s growth in the uterus were a mystery.  Only recently have scientific discoveries and technological advances such as ultrasound allowed us to directly observe life as it develops within the uterus.  From conception to birth, life is a constant coordination of miracles.

During a woman’s childbearing years, one egg matures each month.  The egg is released during ovulation, which is approximately mid-cycle.  If intercourse has occurred, the greatest potential for the uniting of the egg and sperm (fertilization) occurs one to 24 hours after the egg is released (ovulation).

Egg released >> no sperm/egg union >> no implantation >> bleeding/Menstruation >> No pregnancy

Egg released >> sperm and egg unite >> blastocyst implants in uterus >> Fertilization/Pregnancy

Fertilization, also called conception, occurs when a sperm meets an egg and penetrates the egg’s outer layer.  Over a period of several days, the fertilized egg (now called a zygote) travels down one of the two fallopian tubes. As it makes its way to the uterus over a period of two to five days, rapid cell division occurs and the new life progresses from the zygote to the blastocyst stage of human development.  On day five or six, the blastocyst may implant in the lining of the uterus and continue to grow.  Roughly 12 percent of blastocysts fail to implant.