Lecture 5:The Menstrual Cycle - Harvard Universitypeople.fas.harvard.edu/~anth1380/Slides/Lecture 5.pdf · Lecture 5:The Menstrual Cycle •The Ovary •The Menstrual Cycle •Follicular

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Lecture 5:The Menstrual CycleLecture 5:The Menstrual Cycle

•• The OvaryThe Ovary

•• The Menstrual CycleThe Menstrual Cycle•• Follicular phaseFollicular phase•• Luteal phaseLuteal phase

•• Menstrual cycle and mate Menstrual cycle and mate choicechoice

•• Cycle related psychological Cycle related psychological changeschanges

•• Cycle related Cycle related physiological changesphysiological changes

Behavioral Biology of Women 2007

The OvaryThe Ovary The OvaryThe Ovary

Function of the OvaryFunction of the Ovary

•• Target Organ: Generates mature germ cells Target Organ: Generates mature germ cells in response to hormonal control signalsin response to hormonal control signals

•• Endocrine Gland: Sends signals of its own Endocrine Gland: Sends signals of its own

to uterus, the hypothalamus and pituitary.to uterus, the hypothalamus and pituitary.

Ovary with FolliclesOvary with Follicles

Each

immature

egg is

called a

primary

oocyte and

is

contained

in a

follicle.

22

Follicular DevelopmentFollicular Development Decline in Oocytes as we AgeDecline in Oocytes as we Age

The Follicular PhaseThe Follicular Phase

Menstrual CycleMenstrual Cycle

(1) LH

and

FSH

low at

start of

cycle

HH--PP--O AxisO AxisHypothalamusHypothalamus--PituitaryPituitary--Ovarian AxisOvarian Axis

HYPOTHALAMUS

GnRH

(Gonadotropin Releasing

Hormone)

ANTERIOR PITUITARY

Low FSH(2) Low FSH

stimulates

Hypothalamus

to release GnRH

which signals

anterior pituitary

33

HH--PP--O AxisO Axis

(3) Anterior

Pituitary

releases more

FSH and LH

HYPOTHALAMUS

ANTERIOR PITUITARY

OVARY

Follicle

FSH (Follicle Stimulating Hormone) LH (Leutenizing Hormone)

Estrogens

GnRH

(4) FSH

stimulates

follicle to

produce

estrogen

(estradiol)

Follicular DevelopmentFollicular Development Development of Development of Graffian Graffian FollicleFollicle

Graafian Graafian FollicleFollicle

•• Granulosa Cells Granulosa Cells --

Smaller cells on inside Smaller cells on inside

of follicle. Convert of follicle. Convert

testosterone into testosterone into

estradiol under influence estradiol under influence

of FSH.of FSH.

•• Theca Cells Theca Cells -- Cells on Cells on

outside. LH stimulates outside. LH stimulates

theca cells to make theca cells to make

testosterone. Some testosterone. Some

Estrogen made de novo.Estrogen made de novo.

(5) Cells

differentiate

in the

follicle,

forming The

Graffian

Follicle

(6) Increasing

amounts of

Estrogen are

produced by

Graffian

Follicles, one

becomes

“Dominant

Follicle”

44

HYPOTHALAMUS

ANTERIOR PITUITARY

OVARY

Follicle

FSH LH

Estrogens

GnRH Negative Feedback

(7) Increase

in estrogen

sends a

‘Negative

Feedback”

signal to the

Hypothalam

us and

Anterior

Pituitary to

stop

producing

GnRH FSH

HYPOTHALAMUS

ANTERIOR PITUITARY

OVARY

Follicle

FSH LH

Estrogens

GnRH

Negative Feedback

(7) Increase

in estrogen

sends a

‘Negative

Feedback”

signal to the

Hypothalam

us and

Anterior

Pituitary to

stop

producing

GnRH FSH

HYPOTHALAMUS

ANTERIOR PITUITARY

OVARY

Follicle

FSH LH

GnRH

Negative Feedback

Positive Feedback

Estrogens

(8) At some point increasing

estrogen switches to positive

feedback.

(FSHRH & LhRH

(9) Hypothalamus secretes

more GnRh - particularly

LhRH at this point.

55

HYPOTHALAMUS

ANTERIOR PITUITARY

OVARY

Follicle

FSH

GnRH

Negative Feedback

Positive Feedback

Estrogens

LH

(10) When a threshold amount of LhRH

is reached, the anterior pituitary release

a massive dose of LH.

(11) This

massive

surge in LH

causes the

follicle to

rupture and

ovulation to

occur.

OvulationOvulation

Fallopian Tube & Corpus Luteum

Mittelschmerz

66

The Luteal PhaseThe Luteal Phase (12) Empty

follicle is

now called

the Corpus

Luteum.

HYPOTHALAMUS

ANTERIOR PITUITARY

OVARY

Follicle Corpus Luteum

FSH LH

ProgesteroneEstrogens

GnRH

Negative Feedback

Positive Feedback

(13) Corpus Luteum produces

Estrogen and Progesterone

HYPOTHALAMUS

ANTERIOR PITUITARY

OVARY

Follicle Corpus Luteum

UTERUS

FSH LH

ProgesteroneEstrogens

GnRH

Negative Feedback

Positive Feedback

Endometrium, Cervix, Vagina

(14) Estrogen and

Progesterone cause

changes in

reproductive organs.

(15) LH and

Progesterone also

involved in

negative

feedback loops.

77

What is Estrogen Doing?What is Estrogen Doing?

•• Stimulates growth of cells in the lining of the Stimulates growth of cells in the lining of the

uterus, the cervix and the vaginauterus, the cervix and the vagina




•• Causes breast to increase progesterone receptor Causes breast to increase progesterone receptor

densitydensity




•• Causes breast to increase progesterone receptor Causes breast to increase progesterone receptor

densitydensity

•• Initiates proliferative phase in uterusInitiates proliferative phase in uterus


•• Stimulates growth of cells in the Stimulates growth of cells in the

lining of the uterus, the cervix lining of the uterus, the cervix

and the vaginaand the vagina

•• Causes breast to increase Causes breast to increase

progesterone receptor densityprogesterone receptor density

•• Initiates proliferative phase in Initiates proliferative phase in

uterusuterus

•• Causes changes in cervical Causes changes in cervical

mucousmucous

What about Progesterone?What about Progesterone?

•• Builds up the lining of the uterus for Builds up the lining of the uterus for

fertilizationfertilization


•• Builds up the lining of Builds up the lining of

the uterus for fertilizationthe uterus for fertilization

•• Increased concentration Increased concentration

in breast in luteal phasein breast in luteal phase

88


•• Builds up the lining of the uterus for fertilizationBuilds up the lining of the uterus for fertilization

•• Increased concentration in breast in luteal phaseIncreased concentration in breast in luteal phase

•• Initiates secretory phase in uterusInitiates secretory phase in uterus


•• Builds up the lining of the uterus for Builds up the lining of the uterus for

fertilizationfertilization

•• Increased concentration in breast in luteal Increased concentration in breast in luteal

phasephase

•• Initiates secretory phase of Initiates secretory phase of endometriumendometrium

•• Signals the pituitary to stop producing LHSignals the pituitary to stop producing LH

Inside the UterusInside the Uterus

Proliferative Proliferative PhasePhase

•• Estrogen initiates a Estrogen initiates a

““proliferative phaseproliferative phase””

when glands of when glands of

uterine lining thicken uterine lining thicken

and grow and blood and grow and blood

supply proliferatessupply proliferates

Inside the UterusInside the Uterus

Secretory Secretory PhasePhase

•• Progesterone causes Progesterone causes

the uterus to enter a the uterus to enter a

““secretory phasesecretory phase””

when it secretes when it secretes

embryoembryo--nourishing nourishing

substancessubstances

(16)

Progesterone

initiates

Secretory

Phase in

uterus

99

Secretory Phase of UterusSecretory Phase of Uterus

•• The The endometrium endometrium

is now heavily is now heavily

vascularizedvascularized

•• There is active There is active

Secretion of Secretion of

nutrientnutrient--rich rich

medium for medium for

embryonic embryonic

growthgrowth

•• Embryo can only Embryo can only

implant in a implant in a

secretory secretory lininglining

(17) If no

fertilization

occurs, Corpus

Luteum dies

and

endometrium

sloughs off

Changes in Cervical Mucous

• Normally forms a maze of tangled

fibers

• Under influence of estrogen fibers line

up permitting sperm

to get through

Changes in Cervix

• Closes soon after ovulation

Changes in Vagina

• Vagina becomes drier with increasing

progesterone

Changes in the BreastsChanges in the Breasts

•• Estrogen causes breast Estrogen causes breast

cells to start to dividecells to start to divide

1010




•• Estrogen increases Estrogen increases

progesterone receptors progesterone receptors

= increased = increased

progesterone levelsprogesterone levels




•• Increased receptivity to Increased receptivity to

progesterone progesterone ——

increased progesterone increased progesterone

levelslevels

•• Increased tendernessIncreased tenderness




•• Estrogen increases Estrogen increases

progesterone receptors progesterone receptors

= increased= increased

progesterone levelsprogesterone levels

•• Increased tendernessIncreased tenderness

•• Increased nipple Increased nipple

sensitivitysensitivity

What Triggers Menstruation?What Triggers Menstruation?

•• No fertilizationNo fertilization

•• Corpus Luteum Corpus Luteum

regresses after about regresses after about

12 days12 days





12 days12 days

•• Progesterone Progesterone

production drops off production drops off

sharplysharply

1111





12 days12 days

•• Progesterone Progesterone

products drops off products drops off

sharplysharply

•• Endometrium Endometrium

sloughs offsloughs off

The Menstrual Cycle and The Menstrual Cycle and

differences in differences in ……

•• Mate ChoiceMate Choice

•• Mood (including PMS)Mood (including PMS)

•• CognitionCognition

•• Sensation and PerceptionSensation and Perception

The Menstrual Cycle & Mate ChoiceThe Menstrual Cycle & Mate Choice

•• Women preferred males with Women preferred males with

more feminized faces. more feminized faces.

BUT…

Preference for Feminized FacesPreference for Feminized Faces

Cycle PhaseCycle Phase

0

2

4

6

8

10

12

14

16

18

20

Japanese Men Caucasian Men

Low Conception RiskHigh Conception Risk

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Preference for Feminized FacesPreference for Feminized Faces

RelationshipsRelationships

0

2

4

6

8

10

12

14

Short Term

Context

Long Term

Context

Low Conception RiskHigh Conception Risk

The Menstrual Cycle &The Menstrual Cycle &

Male Scent Attractiveness Male Scent Attractiveness

•• Women preferred Women preferred

scent of more scent of more

symmetrical men atsymmetrical men at

midcyclemidcycle

Gangestad & Thornhill 1998

•• No difference when at No difference when at

low fertility risklow fertility risk

The Menstrual Cycle &The Menstrual Cycle &

Male Scent AttractivenessMale Scent Attractiveness

WhatWhat’’s happening here?s happening here?

Gangestad & Thornhill 1998

•• Androstenol Androstenol levels?levels?

•• Type of bacteria?Type of bacteria?

•• Fatty acids?Fatty acids?

•• HLA Gene type?HLA Gene type?

Jealousy and Menstrual PhaseJealousy and Menstrual Phase

•• Krug et al. (l996) found that women had Krug et al. (l996) found that women had

stronger physiological responses to stronger physiological responses to

imagining loss of investment from their imagining loss of investment from their

romantic partner when they were in the romantic partner when they were in the

ovulatory ovulatory phase of the menstrual cyclephase of the menstrual cycle

Mood and PMSMood and PMS

•• Many, many studies. Most Many, many studies. Most show that mood is highest midshow that mood is highest mid--cycle, lowest cycle, lowest perimenstruallyperimenstrually..

Percentages of Women who Report PMSPercentages of Women who Report PMS

25%25%5%5%DizzinessDizziness

69%69%34%34%Skin Skin

BlemishesBlemishes

70%70%30%30%AnxietyAnxiety

76%76%43%43%SadnessSadness

77%77%24%24%BackachesBackaches

77%77%36%36%SwellingSwelling

83%83%34%34%Weight GainWeight Gain

84%84%35%35%Breast PainBreast Pain

Premenstrual Premenstrual

Assessment Assessment

FormForm

Menstrual Menstrual

Distress Distress

QuestionnaireQuestionnaire

SymptomSymptom

(from Nelson, 2000)

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PMS and reproductive hormonesPMS and reproductive hormones

•• No physiological No physiological

abnormalities have abnormalities have

been consistently been consistently

linked with steroid linked with steroid

hormone hormone

concentrations in concentrations in

women with PMSwomen with PMS


•• No physiological No physiological abnormalities have been abnormalities have been consistently linked with consistently linked with steroid hormone steroid hormone concentrations in women concentrations in women with PMSwith PMS

•• Preventing Preventing luteal luteal phase with phase with mifepristone mifepristone (progesterone (progesterone antagonist) did not prevent antagonist) did not prevent symptoms (Schmidt et al., symptoms (Schmidt et al., 1991)1991)


•• No physiological abnormalities No physiological abnormalities have been consistently linked have been consistently linked with steroid hormone with steroid hormone concentrations in women with concentrations in women with PMSPMS

•• Preventing Preventing luteal luteal phase with phase with mifepristone mifepristone (progesterone (progesterone antagonist) did not prevent antagonist) did not prevent symptoms (Schmidt et al., symptoms (Schmidt et al., 1991)1991)

•• But completely shutting down But completely shutting down the cycle with the cycle with GnRH GnRH antagonist antagonist did (Brown et al., 1993)did (Brown et al., 1993)

Do WesternDo Western Women seem to experience PMS more Women seem to experience PMS more

because have many more menstrual cycles?because have many more menstrual cycles?

•• Age of menarche Age of menarche (17 v. 12)(17 v. 12)

•• Age of first pregnancy Age of first pregnancy (18 v. 26)(18 v. 26)

•• Number of pregnancies Number of pregnancies (6 v. 2)(6 v. 2)

•• Amount of time spent in Amount of time spent in lactational lactational amenorrhea amenorrhea (10 years v. 3 months)(10 years v. 3 months)

•• Number of menstrual cycles experienced by HG Number of menstrual cycles experienced by HG women? women? 1010--2020 (Dennis, 1992)(Dennis, 1992)

•• Number of menstrual cycles experienced by Number of menstrual cycles experienced by Modern Western women not on hormonal Modern Western women not on hormonal contraceptives? contraceptives? 300300

Compare hunterCompare hunter--gathering societies to Modern Western: gathering societies to Modern Western:

CognitionCognition

•• When asked on a questionnaire if they have When asked on a questionnaire if they have

menstruation related cognitive changes menstruation related cognitive changes ––

20% of women say 20% of women say ““yes.yes.””

CognitionCognition

•• When asked on a questionnaire if they have When asked on a questionnaire if they have menstruation related cognitive changes menstruation related cognitive changes ––20% of women say 20% of women say ““yes.yes.””

•• No differences in learning and memory No differences in learning and memory across menstrual cycle in most of the across menstrual cycle in most of the dozens of studies.dozens of studies.

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CognitionCognition

•• When asked on a questionnaire if they have When asked on a questionnaire if they have menstruation related cognitive changes menstruation related cognitive changes ––20% of women say 20% of women say ““yes.yes.””

•• No differences in learning and memory No differences in learning and memory across menstrual cycle in most of the across menstrual cycle in most of the dozens of studies. dozens of studies.

•• Academic performance does not seem to be Academic performance does not seem to be significantly affected by menstrual cycle significantly affected by menstrual cycle phase.phase.

Kimura et al. (l988)Kimura et al. (l988)

•• Women performed better with verbal skill Women performed better with verbal skill

(repeating tongue twisters) and muscular (repeating tongue twisters) and muscular

coordination (finger tapping) when estrogen coordination (finger tapping) when estrogen

was high (was high (midluteal midluteal phase).phase).


•• Women performed better with verbal skill Women performed better with verbal skill (repeating tongue twisters) and muscular (repeating tongue twisters) and muscular coordination (finger tapping) when estrogen coordination (finger tapping) when estrogen was high (was high (midluteal midluteal phase).phase).

•• Women performed better on a measure of Women performed better on a measure of spatialspatial--perceptual skill (Rod and Frame test) perceptual skill (Rod and Frame test) during menstruation (early follicular)during menstruation (early follicular)


•• Women performed better with verbal skill Women performed better with verbal skill (repeating tongue twisters) and muscular (repeating tongue twisters) and muscular coordination (finger tapping) when estrogen was coordination (finger tapping) when estrogen was high (high (midluteal midluteal phase).phase).

•• Women performed better on a measure of spatialWomen performed better on a measure of spatial--perceptual skill (Rod and Frame test) during perceptual skill (Rod and Frame test) during menstruation (early follicular)menstruation (early follicular)

•• Postmenopausal women on estrogen replacement Postmenopausal women on estrogen replacement performed better at verbal and motor function than performed better at verbal and motor function than other post menopausal women not on Hormonal other post menopausal women not on Hormonal Replacement TherapyReplacement Therapy

Spatial Ability & Cycle Phase

-0.2

-0.1

0

0.1

0.2

0.3

0.4

Menstrual Midluteal

Z-Score Units

Math Speed/Accuracy&

Cycle Phase

-0.1

0

0.1

0.2

Females Males

Pre-Ovulatory

Mid-Luteal

Z-Score Units

1515

Cycle related physiological changesCycle related physiological changes

•• Body temperatureBody temperature

•• Food intake and carbohydrate metabolismFood intake and carbohydrate metabolism

•• WeightWeight

•• Alcohol metabolismAlcohol metabolism

•• SensitivitySensitivity

•• SpeechSpeech

•• Clinical ailmentsClinical ailments

Body TemperatureBody Temperature

•• Basal body temperature (temp when Basal body temperature (temp when

someone wakes up) is low during follicular someone wakes up) is low during follicular

phase, dips at ovulation and then rises phase, dips at ovulation and then rises

noticeably just after ovulation (~0.4 noticeably just after ovulation (~0.4

degrees) and then continues to rise for the degrees) and then continues to rise for the

rest of the cycle.rest of the cycle.

Body TemperatureBody Temperature

•• Basal body temperature (temp when someone wakes Basal body temperature (temp when someone wakes

up) is low during follicular phase, dips at ovulation up) is low during follicular phase, dips at ovulation

and then rises noticeably just after ovulation (~0.4 and then rises noticeably just after ovulation (~0.4

degrees) and then continues to rise for the rest of the degrees) and then continues to rise for the rest of the

cycle.cycle.

•• Temperature shift is used in research and natural Temperature shift is used in research and natural

family planning to detect ovulationfamily planning to detect ovulation

Basal Body TemperatureBasal Body Temperature

Food Intake and Carbohydrate Food Intake and Carbohydrate

MetabolismMetabolism

•• Food intake (and Food intake (and

basal metabolic basal metabolic

rate) are rate) are

consistently higher consistently higher

during during luteal luteal phase.phase.



•• Food intake (and basal Food intake (and basal

metabolic rate) are consistently metabolic rate) are consistently

higher during higher during luteal luteal phase.phase.

•• Increase in food intake is Increase in food intake is

primarily due to increased primarily due to increased

carbohydrate consumption.carbohydrate consumption.

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•• Food intake (and basal metabolic rate) Food intake (and basal metabolic rate) are consistently higher during are consistently higher during luteal luteal phase.phase.

•• Increase in food intake is primarily Increase in food intake is primarily due to increased carbohydrate due to increased carbohydrate consumption.consumption.

•• Women with PMS show a more Women with PMS show a more significant increase in appetite and significant increase in appetite and carbohydrate craving than women carbohydrate craving than women without PMS.without PMS.

WeightWeight

•• Approximately one third of women report a Approximately one third of women report a

change in body weight (1change in body weight (1--5 pounds) with 5 pounds) with

menstrual phase, usually menstrual phase, usually premenstrually premenstrually or or

perimenstrually perimenstrually depending on study. depending on study.

WeightWeight

•• Approximately one third of women report a Approximately one third of women report a

change in body weight (1change in body weight (1--5 pounds) with 5 pounds) with

menstrual phase, usually menstrual phase, usually premenstrually premenstrually or or

perimenstrually perimenstrually depending on study. depending on study.

•• When estrogens are given experimentally to When estrogens are given experimentally to

both rats and humans, there are increases in both rats and humans, there are increases in

sodium and chloride which cause fluid sodium and chloride which cause fluid

retention.retention.

WeightWeight•• Approximately one third of women Approximately one third of women report a change in body weight (1report a change in body weight (1--5 5 pounds) with menstrual phase, usually pounds) with menstrual phase, usually premenstrually premenstrually or or perimenstrually perimenstrually depending on study. depending on study.

•• When estrogens are given When estrogens are given experimentally to both rats and experimentally to both rats and humans, there are increases in sodium humans, there are increases in sodium and chloride which cause fluid and chloride which cause fluid retention.retention.

•• Fluid retention and increased food Fluid retention and increased food consumption may together account for consumption may together account for cycle related weight fluctuations.cycle related weight fluctuations.

Alcohol MetabolismAlcohol Metabolism

•• In study where In study where men and women men and women were given the were given the same amount of same amount of alcohol (not alcohol (not controlling for controlling for body weight), body weight), women got women got more more intoxicated and intoxicated and had a higher had a higher blood alcohol blood alcohol level than men. level than men.

Alcohol MetabolismAlcohol Metabolism

•• Unclear why Unclear why more affected more affected in latein late luteal luteal phase.phase.

1717

SensesSenses

•• Almost all of the Almost all of the

senses (visual, senses (visual,

auditory, tactile, and auditory, tactile, and

especially olfactory) especially olfactory)

appear to be more appear to be more

acute during the acute during the

follicular phase of follicular phase of

the menstrual cycle.the menstrual cycle.

SensesSenses

•• Almost all of the senses Almost all of the senses (visual, auditory, tactile, (visual, auditory, tactile, and especially olfactory) and especially olfactory) appear to be more acute appear to be more acute during the follicular during the follicular phase of the menstrual phase of the menstrual cycle.cycle.

•• Conflicting studies Conflicting studies about sensitivity to pain, about sensitivity to pain, but many show an but many show an increase sensitivity to increase sensitivity to pain at pain at midcyclemidcycle..

SensesSenses

•• Almost all of the senses (visual, auditory, tactile, Almost all of the senses (visual, auditory, tactile,

and especially olfactory) appear to be more acute and especially olfactory) appear to be more acute

during the follicular phase of the menstrual cycle.during the follicular phase of the menstrual cycle.

•• Conflicting studies about sensitivity to pain, but Conflicting studies about sensitivity to pain, but

many show an increase sensitivity to pain at many show an increase sensitivity to pain at

midcyclemidcycle. .

•• Some researchers speculate that heightened Some researchers speculate that heightened

sensitivity during midsensitivity during mid--cycle may be useful for cycle may be useful for

increasing the probability of coitusincreasing the probability of coitus

SpeechSpeech

•• When asked to give a 3 When asked to give a 3

minute speech both regular minute speech both regular

stutters and non stutters stutters and non stutters

were more were more disfluent disfluent (more (more

repetition, revision, repetition, revision,

disrhythmic disrhythmic phonation, phonation,

interjection and tense interjection and tense

pauses) pauses) premenstrually premenstrually than than

at at midcyclemidcycle. .

Clinical AilmentsClinical Ailments

•• Epilepsy: 58% of female epileptics reported Epilepsy: 58% of female epileptics reported increased seizures increased seizures premenstrually premenstrually compared compared to only 9% during menstruation.to only 9% during menstruation.


•• Epilepsy (58% of female Epilepsy (58% of female

epileptics reported epileptics reported

increased seizures increased seizures

premenstrually premenstrually compared compared

to only 9% during to only 9% during

menstruation.menstruation.

•• Allergies and asthma Allergies and asthma ––

tend to worsen tend to worsen

premenstruallypremenstrually..

1818


•• Epilepsy (58% of female epileptics reported Epilepsy (58% of female epileptics reported increased seizures increased seizures premenstrually premenstrually compared to compared to only 9% during menstruation.only 9% during menstruation.

•• Allergies and asthma Allergies and asthma –– tend to worsen tend to worsen premenstruallypremenstrually. .

•• Herpes and eczema outbreaks more common Herpes and eczema outbreaks more common premenstruallypremenstrually


•• Epilepsy (58% of female epileptics Epilepsy (58% of female epileptics reported increased seizures reported increased seizures premenstrually premenstrually compared to only 9% compared to only 9% during menstruation.during menstruation.


•• Herpes and eczema outbreaks more Herpes and eczema outbreaks more common common premenstruallypremenstrually

•• Migraine headaches more common Migraine headaches more common near ovulation and shortly thereafter near ovulation and shortly thereafter ((perimenstruallyperimenstrually))


•• Epilepsy (58% of female epileptics reported Epilepsy (58% of female epileptics reported increased seizures increased seizures premenstrually premenstrually compared to compared to only 9% during menstruation.only 9% during menstruation.


•• Herpes and eczema outbreaks more common Herpes and eczema outbreaks more common premenstruallypremenstrually

•• Migraine headaches more common near ovulation Migraine headaches more common near ovulation and shortly thereafter (and shortly thereafter (perimenstruallyperimenstrually))

•• Rheumatoid arthritis symptoms are lowest when Rheumatoid arthritis symptoms are lowest when ovarian steroids are low (early follicular phase).ovarian steroids are low (early follicular phase).

Next Time...Next Time...

•• MenarcheMenarche

•• Puberty RitualsPuberty Rituals

Documents

Lecture 5:The Menstrual Cycle - Harvard Universitypeople.fas.harvard.edu/~anth1380/Slides/Lecture 5.pdf · Lecture 5:The Menstrual Cycle •The Ovary •The Menstrual Cycle •Follicular