Lecture 3 - Pregnancy Flashcards
Testosterone
- produced in testes
- controlled by FSH and LH
- principal hormone in male RS
- responsible for reproductive growth
Spermatogenesis
origin and develop of sperm w/n testes
- testes hang outside of body b/c optimal temp. for spermatogenesis is lower than body temp
- stored for four weeks before release
Ejaculation
- semen is released, contains sperm
Male arousal
- blood goes to penis during arousal, engorging spongy tissue, which allows for sperm to be delivered higher up into the vaginal canal
What hormones are present in the female reproductive system?
- estrogen and progesterone (sustain pregnancy)
- produced by ovaries
- controlled by FSH and LH
In simple terms, what is the process of an egg on the ovaries?
- egg released
- pro and est produced
- egg travels down fallopian tube - gets fertilized here
- egg goes to uterus and if fertilized, will implant there
Do both ovaries release eggs every cycle?
No, just one
How long is an avg. mestrual cycle?
approx 28 days
How do progesterone and estrogen influence the menstrual cycle?
- low levels = endometrium is shed, cramps are caused by contraction of blood vessels to prevent bleeding out
- high levels = new lining of uterus is created to receive egg
What does FSH do during the menstrual cycle?
- levels increase during cycle, causing maturation of 15-20 follicles per month
- one of these follicles will fully mature and release an egg
What does LH do during the menstrual cycle?
causes ovulation
Ovulation
- week 2 of menstrual cycle, the release of the most fertile egg
- fertility window is 5 days (how long sperm can live in body) before ovulation to 12-24 hours (shelf life of egg) after
- egg reduces chromosomes from 46 to 23
What are the signs of ovulation?
- lower abdominal pain
- higher basal body temperatures
- changes in cervical mucus
Barrier methods - contraception
- cervical cap or a condom
- ideally 97-98% effective
IUD (intrauterine device) - contraception
- T-shaped device inserted into the top of the uterus to prevent ovulation and thin the uterine lining
- some release progesterone or some are made of copper which is detrimental to sperm
- coverage for 10 years
Hormonal methods - contraception
- estrogen or progesterone - the pill
- tricks body into thinking its pregnant
- usually used for acne treatment or for heavy periods
- plan B is a high dose of this
Pregnancy spacing
- waiting 18-24 months after a live birth reduces risk of pregnancy complications and other health problems
- too soon can cause prematurity
Fertility
- 2 million egg follicles at birth, after puberty most have been absorbed, and only about 400 will go through ovulation
- egg quality and fertility falls with age
- @ about 35, male and female fertility drops
What are the percentages of chromosomal abnormalities at different ages?
- early 20s - 17% of eggs
- 40s - over 75% of eggs
Intrauterine insemination
- fertility treatment in which sperm is injected at the top of the uterus
- more likely in 20s
In Vitro Fertilization (IVF)
- fertility treatment that is more likely given to 30-40 y.o.
1) daily injection of pro and est causes release of high amount of eggs
2) eggs are surgically removed and fertilized in vitro
3) eggs are injected into uterus
Conception
- approx a 6 day window
- 250 million sperm per ejaculation, but only 200 reach egg b/c vagina is very acidic and many sperm will die and get lost
Home pregnancy tests
- cannot be used prior to missed period
- detects level of human chorionic gonadotropin
- 98-99% effective
Only 1 sperm enters the egg and creates a protective barrier to prevent any other sperm enter, then what happens?
- after 2 weeks, the egg reaches the uterus, and releases hCG, in which levels will double every 72 hours and prevent menstrual cycle
Miscarriage
- spontaneous loss before week 20
- early miscarriages are usually due to structural or chromosomal abnormalities or fibroids (fibrous tissue)
What are the rates of miscarriages?
- 50% before implantation (egg implanting elsewhere or never implants, does not effect future pregnancies)
- 33% before week 5
- 25% before weeks 5-7
- <1% after week 12 (due to trauma or genetic abnormality)
What are the early signs of pregnancy?
- missed menstrual cycle
- morning sickness (could be due to rapidly rising levels of hCG)
- hyperemesis gravidarum (extreme morning sickness)
- breast changes (increase 2”, colostrum is produced by 16 weeks, darkened and erect nipples)
- urinary frequency
What does GDF15 have to do with hyperemesis gravidarum?
- levels of this determine morning sickness and how mother reacts to fetus producing this hormone
- high preexisting levels = low risk
- low preexisting levels = potential hyperemesis or bad morning sickness
Nutrition during pregnancy
- mother is sole source of nutrition for baby, so must increase caloric intake by 10-20%
- recommend folic acid for closure of neural tube
- weight gain of 25-30 lbs
What could too much weight gain by either mom or baby result in during pregnancy?
- difficult delivery
- health complications
- increased diabetes and obesity risk for children
Ectopic pregnancy
- embryo develops outside uterus
- baby not getting nutrients or O2
- if implanted in fallopian tube: could burst or hemorrhage, causing loss of fertility of life; most common; could result in mother not knowing shed pregnant
- has to be terminated
Gestational diabetes
- diabetes developing for first time, only during pregnancy
- could be due to family Hx, multiple babies, or larger baby
Preeclampsia
- pregnancy-induced hypertension
- possible development of eclampsia
- the only treatment is to give birth
Physical changes of pregnancy
- “Showing” - fundal height, distance btwn pelvis and top of uterus
- pregnancy “glow” - increased blood volume, dilation of blood vessels
- skin changes like stretch marks, linea nigra, chloasma
Physical changes of pregnancy cont.
- Quickening - first fetal movement felt usually btwn weeks 18 and 24
- center of gravity shifts backwards as fundus height increases
- relaxin relaxes ligaments and tendons in pelvis
- sex drive decreases w/ time, also decreased w/ production of prolactin
