Menstrual cycles Flashcards
Initiation of pregnancy for the sperm
Sperm must move from the vagina through the uterus and into the fallopian tube. Egg and sperm have to meet within 6-24 hours after ovulation
how long after ovulation do the sperm have to meet an egg>?
6-24 hours
What must happen to the sperm that allows them to penetrate the zona pellucida surrounding the egg?
capacitation
Where does fertilization occur?
upper oviduct
survivability (fertilizability) of the ovum?
6-12 hours
survivability of the sperm?
1-2 days
Sexual interest in women peaks when?
Midcycle (right around the time of ovulation) and just before menstruation
volume of ejaculation
1-3 ml, 100 million sperm in each ml
Cervical mucus thinning occurs mid cycle and is stimulated by
estrogen
motility of the female tract
Prostaglandins in semen, estradiol, oxytocin
Highest chance of pregnancy
The day of ovulation or 1-2 days prior. Up to five days prior since thats how long the sperm can survive. Pregnancy chances decrease to zero by one day after ovulation since the egg is only fertilizable for about 6-12 hours
At birth, 1 million germ cells
at puberty, 300,000
When does menopause start
when all eggs are gone…estrogen falls, FSH and LH rise
Cycle
Follicle secretes mainly estrogen (increasing amounts for the first two weeks).
- The estrogen is made by the granulosa cells which make it out of the androgens produced by the thecal cells stimulated by LH The granulosa cells are stimulated by FSH
How many follicles develop in each cycle?
only one, this dominany follicle secretes substances that cause the others to regress
What makes inhibin and what does inhibin do?
Granulosa cells, it turns off FSH after the follicular phase is over and throughout the luteal phase
Cycle starts when
first day of bleeding….period is the start of a cycle not the end
Basal body temp rises when
directy after ovulation