The Menstrual CycleThe Menstrual Cycle

What’s Happening?What’s Happening?

Hormones InvolvedHormones Involved

FSH (follicle stimulating hormone)FSH (follicle stimulating hormone) = released by the pituitary gland > = released by the pituitary gland > signals ovaries to mature an ova (inside signals ovaries to mature an ova (inside a follicle).a follicle).

LH (leutenizing hormone)LH (leutenizing hormone) = released = released to signal ovaries to produce estrogen.to signal ovaries to produce estrogen.

FSH & LHFSH & LH are released into the are released into the bloodstream which will cause the bloodstream which will cause the follicles to begin maturing. follicles to begin maturing.

HormonesHormones

EstrogenEstrogen = as follicles mature, more = as follicles mature, more and more estrogen is being produced and more estrogen is being produced to thicken the lining of the uterus. Also to thicken the lining of the uterus. Also causes the cervical mucous to change.causes the cervical mucous to change.

LH LH = a surge of the LH hormone will = a surge of the LH hormone will cause a mature follicle to ‘burst’ open cause a mature follicle to ‘burst’ open and release an egg > OVULATION. and release an egg > OVULATION.

ProgesteroneProgesterone = causes the uterine = causes the uterine lining (endometrium), to become lining (endometrium), to become covered with mucous.covered with mucous.

The CycleThe Cycle

1-5 Days1-5 Days = FSH = FSH and LH into and LH into bloodstream.bloodstream.

5-13 Days5-13 Days = = Endometrium Endometrium being built up. being built up. Ova is maturing.Ova is maturing.

14-15 Days14-15 Days = = Ovulation occursOvulation occurs

15-27 Days15-27 Days = = Endometrium Endometrium waits for waits for fertilized ova.fertilized ova.

27-30 Days27-30 Days = = Endometrium will Endometrium will shed if ova is not shed if ova is not fertilized > fertilized > menstruationmenstruation. .

Fertilization and Fertilization and DevelopmentDevelopment ZygoteZygote = fertilized ovum = fertilized ovum BlastocystBlastocyst = ball of cells with a = ball of cells with a

cavity in the center.cavity in the center. EmbryoEmbryo = implanted blastocyst. = implanted blastocyst. Amniotic sacAmniotic sac = fluid-filled sac = fluid-filled sac

that surrounds the embryo. that surrounds the embryo. Protects embryo from outside Protects embryo from outside impact and temperature changes.impact and temperature changes.

DevelopmentDevelopment

PlacentaPlacenta = structure that forms = structure that forms along the lining of the uterus as the along the lining of the uterus as the embryo implants. Transfers oxygen embryo implants. Transfers oxygen and nutrients from the mother’s and nutrients from the mother’s blood to the embryo’s blood through blood to the embryo’s blood through the the umbilical cordumbilical cord (connects (connects embryo to mother’s placenta). embryo to mother’s placenta). Embryo’s waste also travels through Embryo’s waste also travels through the umbilical cord.the umbilical cord.

DevelopmentDevelopment

Fetus Fetus = the developing baby = the developing baby from the end of the eighth week. from the end of the eighth week. At this point it is recognizable as At this point it is recognizable as a human being.a human being.