Month by Month

Changes in the first month of pregnancy

Baby’s Growth

Weeks 1 & 2

The average length of gestation is 266 days, which means your baby will be born around 38 weeks after conception. Because many women are not familiar with their fertility cues and do not know when conception happened, pregnancy is generally measured from the first day of the last menstrual period. The average length of pregnancy is 280 days, which means your baby will be born around 40 weeks after the first day of your last menstrual period. By this standard of measuring, your first two weeks of pregnancy happen before your child is conceived.

During this time, the egg that will become your child begins the maturation process and the sperm that will become your child is being produced.

Week 3

This is the week the sperm and egg meet. Some of the decisions about your child, such as gender and if he or she will have any chromosomal problems, will be decided at conception.

After the sperm and egg combined, your newly created baby begins a process of cell division that could rightly be called “explosive.” In these first weeks, perhaps before you even realize you are pregnant, your baby has begun to develop everything it needs to survive until birth. By the third week of life your baby ‘s heart is already pumping blood on its own.

Week 4

The creation of your baby begins before he is even attached to your uterine lining. As the egg divides and grows, cells begin to be specialized. The fertilized egg will create your baby, the placenta, the amniotic sac and the amniotic fluid. Approximately 10 days after fertilization, your baby implants in the uterus. The lungs, heart and spinal cord begin to form.
By the end of the fourth week your baby is less than .03 oz, and is approximately 1/8 of an inch long.

Mom’s Changes

Don’t forget about the importance of being as healthy as possible during this exciting time of your life. Be sure you are eating a variety of foods, staying active and getting as much rest as necessary for the healthy functioning of your body. Remember, you and your baby will both be using your body, so it is vitally important to stay as well nourished and rested as possible.

When the egg becomes fertilized, your body begins producing higher levels of progesterone which prevent menstruation and keep the pregnancy healthy. It is initially produced by the ovary, but production will eventually be taken over by the placenta.

In response to the progesterone, the uterine lining thickens and the blood supply to the uterus increases. The cervix plugs with mucus to provide a protective barrier. Your uterus begins to enlarge and soften to allow implantation.

As your uterus begins to change, you may notice some pre-menstrual type cramping. The increased metabolic rate and the growth of the uterus causes an increased need to urinate. You will probably be more tired than usual and may even have short periods of faintness. The pregnancy hormones trigger the maturation process in the mammary glands, which may cause breast tenderness or soreness.

During this first month, you may wonder if you are pregnant. You can watch for the early signs of pregnancy and confirm your pregnancy with your midwife if you want to be sure.

The following concerns are commonly experienced during this month.

  • Urinary Frequency
  • Breast Soreness
  • Increased Fatigue
  • Decreased Libido
  • Faintness
  • Nausea and Vomiting
  • Pregnancy Symptoms
Jennifer (Author)