Target: I will be able to identify the stages of fetal development during each trimester of pregnancy Pg. 33 Stages of Pregnancy: 1 st Trimester: First 3 months of pregnancy after conception Month 1: Very few noticeable changes occur in the mother’s body
Month 2: Pregnancy symptoms increase: including frequent urination, morning sickness, breast tenderness, fatigue, heartburn, faster heart-beat, and about 2 pounds weight gain Miscarriages happen (about 15%): Miscarriage is the loss of pregnancy before 20 weeks
2 nd Trimester: Months 4-6 of pregnancy Physical changes in the mother become more visible including breast enlargement as milk glands increase and increased waistline as the uterus enlarges 50-60 times the original size.
Movement of the fetus can be felt by the mother by the 5 th month. Some women have Braxton-Hicks contractions. This is the uterus’s way of practicing for labor and delivery.
3 rd Trimester: Months 7-9 of pregnancy Back pain becomes common; feet and legs swell with prolonged standing The uterus has expanded from the pelvis to the bottom of the rib cage
The cervix begins to open (dilate) to prepare for delivery
Babies may be born prematurely (any birth before 37 weeks) and will have a 20% survival rate. Pregnancy Time Lapse
Stages of Fetal Development: 1 st Trimester: At the end of the 1 st month: the embryo has a heartbeat, a brain, and spinal cord By the end of the 2 nd month: The embryo is recognizable as a human, and has started to form arms and legs; as well as fingers, ears, and toes
Changes triggered by hormones begin to make external sex organs End of the 1 st trimester: the fetus is about 3 inches long, weighs 1 ounce, begins moving, begins making urine, and its’ heart has 4 chambers
2 nd Trimester: The fetus can be visibly identified as male or female around 20 weeks
By the end of the 4 th month: fingernails, toenails, eyebrows, and eyelashes have grown. Teeth, taste buds, and lips appear, hair grows, and hundreds of thousands of eggs form in the ovaries in female fetuses. The fetus can bend it’s arms and make a fist
During the 5 th month, the heartbeat can be detected with a stethoscope By the end of the 2 nd trimester: the fetus is about 12 inches long and weighs 1 pound Ultrasound at 20 Weeks
3 rd Trimester: This is a period of the greatest fetal growth; when it gains most of its weight
Eyelids unfuse around week 28 A full term baby is usually 19-21 inches long and weighs between 6 and 9 pounds Embryonic Development Time Lapse Summary:
HOW BABIES GROW Divide your page into 3 sections (like a peace sign) Label the sections: Trimester 1, Trimester 2 and Trimester 3 In each stage, draw the fetus and its features You may need to divide each section into multiple sections to show specific changes during specific months. Use a minimum of 4 colors. Pg. 32