Fetal/Maternal changes during gestation Flashcards
Gestational age in weeks
4 (embryo)
Fetal Size and Development
1/8 inch (4 mm.)
fertilized egg implants on endometrium of uterus: single chambered heart beating; cell differentiation occurs; susceptible to teratogens
Gestational age in weeks
4 (embryo)
Maternal Changes
basal body temperature remains elevated after ovulation; nausea/morning sickness(~50% have); fatigue; no menstruation or slight spotting; breasts feel tight and tingly; can have positive pregnancy test
Gestational age in weeks
8
Fetal Size and Development
1 inch (28 mm.)
1 gram
very rudimentary facial features forming; arm and leg buds; highly susceptible to teratogens; primitive functioning of systems; placenta and umbilical cord forming; head makes up nearly half of embryo’s length, genetic expression of sex differentiationbegins
Gestational age in weeks
8
Maternal Changes
morning sickness worse now; mucus plug forms in cervix; breasts larger; uterus softens; frequent urination
Gestational age in weeks
12 (fetus)
Fetal Size and Development
3 1/2” (9 cm) 1/2 oz. (15 gm.)
eyelids formed, closed; genitals forming; finger/ toe nails forming; fingers well developed; kicks legs, closes fingers, bends wrist, turns head; frowns, opens/ closes mouth; organ differentiation occurring
Gestational age in weeks
12 (fetus)
Maternal Changes
morning sickness lessens by end of month; bladder pressure lessens; fetal heart tones audible by Doppler
Gestational age in weeks
16
Fetal Size and Development
6 1/2” (16 cm.)
4 oz. (100 gm.)
functioning liver and thyroid gland; blood forming in marrow; hair forming on head; lanugo is forming; skeletal ossification occurs and is visible on x-ray (though x-ray should be avoided); fetus begins to moveabout freely; placenta formed completely
Gestational age in weeks
16
Maternal Changes
uterus contracts (but she is unable to feel); blood volume and cardiac output increases; quickening
Gestational age in weeks
20
Fetal Size and Development
10” (25 cm.)
10 oz. (300 gm)
vernix caseosa forms on skin; period of rapid growth; finger/toe nails are formed completely; favorite position to sleep in; periods of sleep/awake like newborn; blood supply to lungs increases
Gestational age in weeks
20
Maternal Changes
fetal heart tones clearly audible by stethoscope; definite “quickening” noticed by this point.
Gestational age in weeks
24
Fetal Size and Development
12” (30 cm.)
1 1/4 lbs. (600 gm.)
skin less transparent and and wrinkled; vernix continues to accumulate; body well proportioned; eyebrows/eyelashes developing; baby can hear sounds; baby stretches, kicks and sucks thumb
Gestational age in weeks
24
Maternal Changes
period of rapid weight gain; stretch marks; drop in hemoglobin; linea nigra forms but will disappear/lighten after delivery; chloasma will appear but disappears after delivery; we know these latter 2 events are due to hormonal influences, but it is unclear why they occur.
Gestational age in weeks
28
Fetal Size and Development
14” (35-37 cm.)
2 1/2 lbs. (1000 gm.)
testes begin to descend in male fetus; eyelids open; fingerprints set; storage of subcutaneous fat begins; rapid growth continues; bones are developed but are soft and flexible; lungs have matured enough tosupportrespirationoutside the uterus (barely, more on this later)
Gestational age in weeks
28
Maternal Changes
blood volume is highest at this stage; weight gain continues; breathing may be difficult at times; heartburn; Braxton-Hicks contractions are stronger
Gestational age in weeks
32
Fetal Size and Development
16” (40-42 cm.)
4 lbs. (1700-
1800 gm.)
greater subcutaneous fat; period of rapid growth; body covered with vernix; storage of iron, nitrogen, and other nutrients