Chapter 9 - Nursing Care of the Growing Fetus Flashcards
Define ovum
the term used for the egg/baby from the time of ovulation to fertilization
Defne zygote
the term used for the egg/baby from the time of fertilization to implantation
Define embryo
the term used for the egg/baby from the time of implantation to 5-8 weeks
Define fetus
the term used for the baby from the time of 5-8 weeks to term
Fetal growth and development can be divided into these three categories
pre-embryonic (0-2 wks) embryonic (3-8 wks) fetal (8wks - term)
The window for fertilization is
72 hrs - 48 before ovulation and 24hrs after ovulation Therefore, to best promote pregnancy the woman should attempt fertilization 5-3 days prior to expected ovulation and 2 days after.
Fertilization generally occurs in the
outer 1/3 of the fallopian tubes
After fertilization, the zygote
migrates over the next 3-4 days mitotic division begins
A zygote with large cells on the exterior and a fluid interior is termed
a blastocyst
Fertilization depends on these factors
- equal maturation of both sperm and ovum
- ability of sperm to reach the ovum
- ability of sperm to penetrate the zona pellucida and cell membrane to acheive fertilization
Implantation occurs after
8-10 days after fertilization
as many as 50% of zygotes never acheive implantation
Spotting occuring from zygote implantation may be misinterpreted as a menstrual period. This error would cause a difference of ______ when calculating the due date
4 weeks late
Human chhorionic gonadotropin (hCG) is secreted by the ______. It’s function is to…
- trophoblast cells of the corpus leuteum within the zygote/embryo and by the placenta
- ensures the corpus leuteum continues to produce progesterone and estrogen so that uterine endometrium can grow and vascularize
The chorionic villi are
- villi that reach out from the trophoblast cells into the uterine endometrium to form the placenta
- It produces hCG, human placental lactogen (hPL), estrogen and progesterone.
The rate of urteroplacental blood flow ranges from ____ to _____ over the course of the pregnancy
- 50 mL/min at 10 weeks
- 500-600 mL/min at term
The most efficient maternal position for uterine perfusion annd placental circulation is her
left side.
Lying supine could cause compression of the vena cava and supine hypotension
Progesterone is produced by the ______. Its function is to…
- First by the corpus luteum, the by the placenta after 12wks
- Maintenance of the endometrial lining
- appears to reduce contractility of the uterus
Estrogen is produced by the ______. Its function is to…
- First by the corpus luteum, then by the placenta
- promotes mammary gland development to prepare for lactation
- stimulates uterine growth
Human placental lactogen hPL (aka human chorionic somatoammotropin) is produced by the ______. Its function is to
- Placenta (6wks-peaks a term)
- promotes mammary gland growth and regulates maternal glucose, protein and fat levels
The amniotic membrane (amnion) function is to…
- support and produce amniotic fluid
- produce phospholipids that initiate prostaglandins to trigger labor.
The function of amniotic fluid is to…
- shield the fetus against pressure or a blow against the mother’s abdomen
- Protect the fetus from Temperature change
- Cushion the umbilical cord & fetal O2 supply
- slighlty alkaline (7.2)
- levels fluxuate
- ranges from 800-1200mL
Define Hydrammnios
excessive amniotic fluid (>2000mL)
may be caused by fetal inability to swallow or diabetes in the mother
Define oligohydramnios
- reduction in amount of amniotic fluid (<300mL)
*
The umbilical cord should contain
1 vein and 2 arteries
1:1 ratio indicates chromosomal disorders (esp. kidney & heart)
The ectoderm forms what body portions
- CNS
- PNS
- integument
- sense organs
- mucus membranes of anus, mouth and nose
- mammary glands
The mesoderm forms what body portions
- Supporting structures (connective tissue, bone, cartilage, muscle, ligaments, tendons)
- Kidneys & ureters
- Reproductive system
- Lymph
- Circulatory systems & blood
The endoderm forms what body portions
- Gi tract, Pericardial, plaural, and peritoneal cavity lining
- Repiratory tract
- Tonsils, parathyroid, thymus glands
- Bladder and urethra
The fetal heart starts beating as early as the
24th day
(it can be heard via doppler by the 6th or 7th wk)
Once stabilized, the normal fetal heart rate ranges from
110-160 beats/min
At birth the infant’s pulse rate is between
80-140 beats/min
The infant’s hemoglobin and hematocrit lab values are approximately
- hemoglobin: 17.1g/100mL
- hematocrit: 53%
The primary test for fetal maturity is the
lacithin/sphingomyelin (L/S) ratio in surfactant
2:1 is normal/goal at birth
