Understanding Your Unborn Baby

Your body is going through a lot during pregnancy, but your baby is growing and changing even more.

So much happens during pregnancy. Our bodies do amazing things during this journey to create new life. Once you become pregnant, the lining of your uterus thickens and its blood vessels enlarge to nourish your baby. As your pregnancy progresses, the uterus expands to make room for the growing baby. By the time your baby is born, your uterus will be many times its normal size.



Amniotic Sac: A thin-walled sac that surrounds the baby during pregnancy. The sac is filled with amniotic fluid which is a liquid made by the baby and the amnion (the membrane that covers the fetal side of the placenta). The amniotic sac protects the fetus from injury and helps to regulate his temperature.

Cervix: The lower part of the uterus that projects into the vagina and opens/dilates at birth. Made up of mostly fibrous tissue and muscle, the cervix is circular in shape.

Egg: The female reproductive cell produced in and released from the ovaries; also called the ovum.

Fertilization: Joining of the egg and sperm.

Fetus: The term for an unborn baby from the eighth week after fertilization until birth.

Placenta: An organ, shaped like a flat cake, which only grows during pregnancy and provides nourishment to and takes waste away from the fetus.

Sperm: A male cell that is produced in the testes and can fertilize a female egg cell.

Umbilical Cord: A rope-like cord connecting the baby to the placenta. The umbilical cord contains two arteries and a vein that carry oxygen and nutrients to the fetus and waste products away from the baby.

Uterine Wall: The wall of the uterus.

Uterus (also called the womb): The uterus is a hollow, pear-shaped organ located in a woman's lower abdomen, between the bladder and the rectum, that sheds its lining each month during menstruation. When a fertilized egg (ovum) becomes implanted in the uterus, the baby develops there.

Vagina: The part of the female genitals, behind the bladder and in front of the rectum, that forms a canal extending from the uterus to the vulva. Also called the birth canal.

So what's really going on inside your uterus? Let's take a look.

Month 7

  • The eyes can open and close and sense changes in light.
  • Lanugo (the soft, fine hair that covers a fetus) begins to disappear.
  • The fetus kicks and stretches.
  • The fetus can make grasping motions and responds to sound.

Month 8

  • With its major development finished, your baby gains weight very quickly.
  • Bones harden, but his skull remains soft and flexible for delivery.
  • The different regions of his brain are forming.
  • Taste buds develop and your baby can taste sweet and sour.
  • Your baby may now hiccup.

Month 9

  • Your baby usually turns into a head-down position for birth.
  • His skin is less wrinkled.
  • His lungs mature and are ready to function on their own.
  • Sleeping patterns develop.
  • He will gain about ½ pound per week this month.