Menstruation, Conception, and Fetal Development Flashcards
(137 cards)
1
Q
What is the average age for menarche?
A
12 years old
2
Q
How long does a typical menstrual cycle last?
A
29 days on average (range: 21–35 days)
3
Q
What is the average range of menstrual blood flow in milliliters?
A
25–60 mL
4
Q
What is the normal duration range for menstrual bleeding?
A
2 to 8 days
5
Q
What is the function of FSH (Follicle Stimulating Hormone) during the menstrual cycle?
A
Stimulates the growth of ovarian follicles.
6
Q
hat is the function of LH (Luteinizing Hormone) during the menstrual cycle?
A
Triggers ovulation and stimulates growth of the corpus luteum.
7
Q
What happens to the corpus luteum if the woman is not pregnant?
A
It disintegrates and triggers menstruation.
8
Q
What is the function of estrogen during the menstrual cycle?
A
Stimulates the growth of the endometrial lining.
9
Q
What is the function of progesterone in preparing for pregnancy?
A
Thickens the endometrial lining to prepare the uterus for fertilized ovum implantation.
10
Q
What happens during the follicular phase of the ovarian cycle, and when does it occur?
A
Follicles mature and ovulation begins; occurs during days 1–14.
11
Q
What occurs during the luteal phase of the ovarian cycle?
A
The ovum leaves the follicle and the corpus luteum develops; it either supports pregnancy or disintegrates to trigger menses.
12
Q
What are the days of the luteal phase in a 28-day cycle?
A
Days 15–28.
13
Q
What triggers menses in the menstrual cycle?
A
Disintegration of the corpus luteum when fertilization does not occur
14
Q
When does the menstrual phase occur in the uterine cycle?
A
Days 1–6.
15
Q
What causes the end of the menstrual cycle around day 27–28?
A
The corpus luteum breaks down, leading to a drop in estrogen and progesterone, which triggers menstruation.
16
Q
What happens during the proliferative phase of the uterine cycle?
A
Estrogen causes endometrial cells to enlarge, lengthen, and twist to prepare for ovulation.
17
Q
When does the proliferative phase occur?
A
Days 7–14 in a 28-day cycle.
18
Q
What happens during the secretory phase of the uterine cycle?
A
Increased vascularity prepares the uterus for implantation, causing bloating and cramping.
19
Q
What hormone maintains high levels of estrogen and progesterone early in pregnancy until the placenta takes over?
A
hCG (human chorionic gonadotropin).
20
Q
Where does fertilization typically occur in the female reproductive system?
A
In the ampulla, the outer third of the fallopian tube (either left or right).
21
Q
What is formed when the egg and sperm each contribute 23 chromosomes?
A
A diploid zygote with 46 chromosomes.
22
Q
When is the sex of the baby determined? What would the sex of M/F look like?
A
At fertilization (XX = female, XY = male).
23
Q
What is the correct sequence of early cell development after fertilization?
A
Blastomeres → Morula (12–32 cells) → Blastocyst → Implantation.
24
Q
What are blastomeres?
A
The initial cells formed from the first cell divisions after fertilization.
25
What is a morula and when does it form?
A solid ball of 12–32 cells that forms after the blastomeres multiply.
26
What does the morula develop into?
A blastocyst.
27
What is a blastocyst?
A fluid-filled structure that forms from the morula and is what implants into the uterus.
28
When does implantation of the blastocyst occur after fertilization?
7–10 days after fertilization.
29
How long is an ovum viable after release?
24 hours
30
How long can sperm remain viable inside the female body? When is it most fertile?
48–72 hours, but most fertile in the first 24 hours.
31
What is capacitation in sperm?
A process that makes sperm more active and able to move better.
32
What is the acrosomal reaction?
Enzymes from the sperm’s head are released to penetrate the egg.
33
When does the blastocyst begin dividing into germ layers?
10–14 days after conception.
34
What are the three primary germ layers the blastocyst divides into?
Endoderm, Mesoderm, and Ectoderm.
35
What is the function of the three germ layers?
They form all tissues, organs, and organ systems in the body
36
When does the embryonic membrane develop?
At the time of implantation.
37
What two layers make up the embryonic membrane?
Chorion and Amnion.
38
What is the purpose of the amniotic fluid?
To protect and support the embryo.
39
What is the function of the yolk sac before the placenta develops?
It provides nutrients and gas exchange between baby and mother.
40
What is the yolk sac responsible for until week 8 of pregnancy?
Producing red blood cells.
41
What takes over RBC production after week 8 of pregnancy?
The fetal liver.
42
What is the outermost membrane that contains the placenta, amnion, embryo, and yolk sac?
Chorion.
43
What are chorionic villi?
Finger-like projections that become part of the placenta.
44
What is the function of the chorionic villi?
They handle gas, nutrient, and oxygen exchange.
45
46
What is the amnion and where does it arise from?
The amnion is part of the chorion and arises from the ectoderm.
47
What does the amnion contain?
Amniotic fluid
48
What is the main function of the umbilical cord?
To create a circulatory pathway for the embryo.
49
What structure does the umbilical cord develop from?
The amnion.
50
What is the vessel composition of the umbilical cord?
Two arteries and one vein (AVA).
51
What do the two umbilical arteries do?
Carry deoxygenated blood away from the baby.
52
What does the umbilical vein do?
Carries oxygenated blood from the placenta to the baby.
53
What is Wharton’s jelly and why is it important?
A protective substance surrounding the vessels to prevent compression.
54
How long is the umbilical cord at full term?
About two feet long.
55
What is the main function of the placenta?
To create a metabolic and nutrient exchange between maternal and fetal circulation through respiratory, nutrient, waste elimination, and endocrine functions.
56
When does the placenta begin to develop and when is it fully formed?
It begins developing in the third week of embryonic development and is fully formed at 10 weeks.
57
What is the respiratory function of the placenta?
Acts as the baby’s lungs by transferring maternal hemoglobin across the placental membrane into fetal circulation. Oxygen is taken from the maternal blood and delivered to the fetus.
58
What is the nutrient function of the placenta?
Delivers macronutrients and carbohydrates from maternal blood to fetal blood through the placental membrane to support fetal development.
59
What is the waste elimination function of the placenta?
Functions like the kidneys by clearing hydrogen ions, bicarbonate, CO₂, lactic acid, and creatinine from fetal blood into maternal blood through the placental membrane.
60
What hormones does the placenta produce in its endocrine function?
hCG, estrogen, and progesterone.
61
What is the immunity function of the placenta?
Transfers IgG antibodies from mother to fetus to provide temporary immunity during pregnancy and shortly after birth.
62
What color is the maternal side of the placenta and where is it connected?
Red; connected to the uterus.
63
What color is the fetal side of the placenta and where is it connected?
Silver; connected to the amnion.
64
What important structures are found on the fetal side of the placenta?
Chorionic villi and their circulation.
65
What is the intervillous space?
A space filled by maternal veins that creates a pool of maternal blood for nutrient and gas exchange.
66
What happens in the intervillous space?
Exchange of fetal and maternal nutrients and metabolism across the placental membrane.
67
Do maternal and fetal blood mix in the placenta?
No, they come in close contact but do not mix.
68
What role does amniotic fluid play in regulating the fetus?
Helps control the baby's temperature.
69
What is a major component of amniotic fluid at 20 weeks?
Fetal urine (about 1L/day).
70
What happens when a woman’s water breaks?
The 700–800 mL of amniotic fluid is released.
71
What are the protective roles of amniotic fluid?
Cushions the umbilical cord and protects the embryo from mechanical injury.
72
What are fraternal twins also called?
Dizygotic twins.
73
Do fraternal twins share the same egg, sperm, or placenta?
No, each has its own egg, sperm, blastocyst, and placenta.
74
How genetically similar are fraternal twins?
No more than other siblings in the family.
75
Where do fraternal twins implant?
In different spots on the uterine wall.
76
What are identical twins also called?
Monozygotic twins.
77
What do identical twins share?
The same egg, sperm, blastocyst, and often the same placenta.
78
Do identical twins have their own amnion?
Yes, each twin usually has a separate amniotic sac.
79
What determines the number of amnions and chorions in identical twins?
The timing of the cell division.
80
How do conjoined twins form?
Incomplete division of the embryonic disk during the blastocyst stage.
81
How can conjoined twins be connected?
By skin only or internal tissues/organs.
82
When is surgical separation of conjoined twins possible?
Only if it's anatomically possible
83
What are the 3 phases of fetal development?
Pre-embryonic, Embryonic, Fetal.
84
How is pregnancy calculated?
10 lunar months, 40 weeks, or 280 days from the last menstrual period.
85
How long does the pre-embryonic phase last?
Up to 15 days.
86
What is the developing baby called in the pre-embryonic phase?
Zygote.
87
When is the embryo most vulnerable ? and what is the embryo most vulnerable to ?
During the first 8 weeks and birth defects and damage from teratogens.
88
When can pregnancy first be detected?
As early as 4 weeks.
89
What happens to the heart by the end of 4 weeks?
It beats in a regular rhythm.
90
What is the fetal shape at 5 weeks?
C-shaped with a tail.
91
What does the fetal tail become by 8 weeks?
It disintegrates and becomes part of the tailbone
92
What begins to form at 5 weeks?
Limb buds and skeletal shape.
93
What happens to the eyes and head at 7 weeks?
Eyelids form, eyes move upward and closer, and the head becomes rounded and erect.
94
What important liver function begins at 8 weeks?
The liver takes over the function of the yolk sac and makes the RBC
95
How big is the embryo at the end of 8 weeks?
About 1.2 inches.
96
What are key developments in the embryonic phase related to the nervous system?
Brain develops through the neural tube, and cranial nerves are present.
97
What happens between 8–12 weeks of the fetal phase?
All organs are developed and need to mature.
98
At what week can the sex of the fetus be identified?
16 weeks
99
When does the mother typically start to feel fetal movement?
20 weeks
100
Around what length (crown to rump) is the fetus at 20 weeks?
7.5 cm
101
About how much does the fetus weigh at 20 weeks?
15.2 to 3 oz
102
What fetal measurement is used at 20 weeks because the fetus is still curled in a C-shape?
Crown-to-rump length
103
Why are limbs not used for fetal measurements at 20 weeks?
Because the fetus’s body is still in a C-shaped position and limbs are not fully extended.
104
What is the first fetal movement that the mother can feel called? And when can a mother feel it
Quickening and at 20 weeks
105
Which two reflexes begin to develop due to neuro and muscular maturity at 20 weeks?
Sucking and swallowing
106
What coating begins to form on the fetal skin at 20 weeks to protect it?
Vernix caseosa
107
What is the fine, downy hair that starts to grow on the fetus’s body at 20 weeks?
Lanugo
108
What is "Brown Fat" , what is the function and when does it develop?
20 weeks
Subcutaneous fat deposits used to regulate body temperature and make the skin less transparent
109
What process involving the fetal spinal cord begins at 20 weeks?
Myelination
110
What visible features like nails begin to form around 20 weeks?
Fingernails and toenails
111
What lung substance begins forming at 24 weeks to prevent alveolar collapse?
Surfactant
112
What is the role of surfactant in fetal lung development?
It reduces surface tension in the alveoli, preventing collapse during exhalation and helping breathing after birth.
113
What major system begins developing at 24 weeks alongside surfactant production?
Respiratory system
114
Around how much does the fetus weigh at 24 weeks?
1 pound and 10 ounces
115
When do fetal eyelids begin to open and close?
28 weeks
116
At what gestational age can the central nervous system begin regulating breathing and body temperature?
28 weeks
117
At what point is the fetus approximately two-thirds of its final length?
28 weeks
118
When does the fetus begin to look more like a full-term baby (less red and wrinkled)?
32 weeks
119
At what week are fingernails and toenails fully developed?
32 weeks
120
When do additional brown fat deposits begin forming to help with thermoregulation?
32 weeks
121
At what week is the fetus considered full term?
38–40 weeks
122
When is surfactant production considered adequate to support independent breathing?
38–40 weeks
123
When do maternal antibodies begin transferring to the fetus?
38–40 weeks
124
What vaccination given in the third trimester provides antibodies to the fetus?
TDAP shot
125
At term, where on the body might lanugo still be visible?
Shoulders
126
What substance is still present on the skin at full term that helped protect the fetus in utero?
Vernix caseosa
127
What does the acronym TORCH stand for in pregnancy-related infections?
Toxoplasmosis
Other (Hepatitis, Syphilis, HIV)
Rubella
Cytomegalovirus
Herpes
128
Why are TORCH infections dangerous during pregnancy?
They can cross the placenta and harm the developing fetus.
129
What infection is commonly linked to cat litter and undercooked meat during pregnancy?
Toxoplasmosis
130
What are three ways pregnant women can contract toxoplasmosis?
Cat feces, undercooked/raw meat, contaminated fruits/vegetables
131
What food safety recommendation is given to pregnant women to avoid toxoplasmosis?
Avoid sushi and undercooked meats, and wash fruits/vegetables thoroughly
132
What is the treatment of choice for syphilis in pregnancy?
IM Penicillin
133
Why is tetracycline not used to treat syphilis during pregnancy?
It is toxic to the fetus
134
What is done if a pregnant woman with syphilis is allergic to penicillin?
Penicillin desensitization in a hospital setting
135
When can a woman receive the rubella vaccine if she is not immune during pregnancy?
After childbirth
136
Which TORCH infection is part of the herpes family and can be passed to the fetus at birth?
Cytomegalovirus (CMV)
137
What delivery method is required if a pregnant woman has active herpes lesions?
Cesarean section (C-section)
