Overview of Common Hormonal Influences of Pregnancy

About Midwives: Pregnancy Information
Creations Unlimited
Estrogen
Human Chorionic Gonadotropin [HCG]
Human Placental Lactogen [HPL] 
Hypnosis For Birth and HypnoBirthing

Oxytocin

Resources

Progesterone

Terms

Prolactin

Thyroxin

Prostiglandin

Ecstatic birth - nature’s hormonal blueprint for labor

http://sarahjbuckley.com/articles/ecstatic-birth.htm
Hormones of Pregnancy and Labor pdf graphic

Action

Effects

Estrogen

Estrone E1 [menopause]
Estradiol E2 [non-pregnant]
Estriol E 3 increases 1000 fold in pregnancy
Produced from:
Ovary
Adrenal Cortex
Fetoplacental Unit (After the 7th week of gestation, a 50 % increase in secretion is ascribed from the placenta
Secreted with precursors from fetal liver and adrenals
+Controls growth and function of the uterus
+Hypertrophy of the musculature
+Proliferation of the Endometrium
+Increased blood supply to the utero-placental unit (estriol)
+Breast development: ducts, alveoli, nipples
+Enlargement of the external genitalia
+Increased pliability of connective tissue (becomes hygroscopic and softer)
+Relaxation of pelvic joints and ligaments
+Streachabilty of the cervix
+Decreased gastric secretion of hydrochloric acid and pepsin
+Increased pigmentation of the skin (increased melanocyte-stimulating hormone to pituitary)
+Sodium and water retention
+Vascular changes: 50% increase in clotting potential of blood fibrinogen (Factor 1)
+Increased production of estriol in the late trimester
+Psychological changes
+Increased breast size and tenderness
+Lordosis, backache
+Cervical dilatation
+Indigestion, nausea, heartburn, decreased absorption of fat
+Cervical dilatation
+Enhances rhythmic uterine contractions and increased vascularity and responsiveness to Oxytocin stimulation; may stimulate Prostiglandin production
+Contributes to headaches for some women
+Hyperpigmentation: chloasma, darkened genitalia, areola, linea nigra
+Edema: increased plasma volume (physiologic anemia0
+Increased sedimentation rate
+Palmar erythema, vascular spiders, angiomata
+Emotional labiality and libido changes
+Common symptoms also seen with PMS
+Measurement of estriol in the urine or amount of amniotic fluid might be an indicator of fetal well being
Decreased: anacephaly; Addison's disease in mother; fetal demise; drug use such as antibor glucose in the urine
Increased: twins, erythroblastosis
+Tenderness of the symphysis pubis
Progesterone [increases 10 fold in pregnancy]

Produced from the Corpus luteum of the ovary for the first 7 weeks of pregnancy; then by the maternal-fetal unit

+Development of the decidual cells in the endometrium
+Probably suppresses maternal immunologic response to the fetus
+Decreased contractility of pregnant uterus
+Development of lobule-alveolar system of the breasts (secretory character)
+Hypothalmic center changes during pregnancy
+Increased body temperature by 0.5o C until midpregnancy, then it becomes normal
+Extensive fat depot storage
+Stimulation of the respiratory center, inducing hyperventilation
+Stimulates naturiusresis
+Relaxation of smooth muscle
+Decreased stomach motility
+Decreased colonic activity
+Decreased tone of bladder and ureter (dilatation throughout the urinary system
+Decreased vascular tone
+Decreased motility and distention of the ducts of the gallbladder
+Meets early nutritional needs of the embryo by deposition of glycogen
+Prevention of premature labor
+Breast tenderness
+Average body fat stored is 8.8#; energy stores for protection of the mother and fetus during starvation or hard physical exertion
+Decreased alveolar and arterial PCO2 of the mother to facilitate easy transfer of CO2from fetal to maternal blood
Sensations of being overly warm by pregnant women, increased perspiration
+Stimulate secretion of aldosterone (sodium saver) to maintain water and electrolyte balance
+Nausea, reflex esophagitis, indigestion
+Delayed emptying with readsorption of water from the bowel resulting in constipation and hemorrhoids
+Stasis of urine with increased frequency of urinary tract infections
+Reduced diastolic blood pressure, venous dilatation with stasis in lower limbs-dependent edema, varicosities
+Slow gallbladder emptying with thickening of the bile--possible predisposition to gallstones and gallbladder symptoms
Oxytocin

Produced from the Hypothalamus to pituitary for release

+Stimulates uterine contractions-is not responsible for initiating labor, but increases the intensity of contractions
+Ferguson's reflex-release of oxytocin by cervical and vaginal distention during labor
+Stimulates milk let-down and ejection
+Synthetic pitocin used to induce labor
+Uterine involution postpartum
+Lactation
Human Chorionic Gonadotropin [HCG]

Produced by the Placenta by the syncyto-trophoblasts    HCG

Maintains the function of the corpus luteum in early pregnancy
+Appears as early as 8 days post conception
+Peaks at 60-90 days when corpus luteum function is no longer essential to maintain the pregnancy
+Peak secretion is 500,000-1,000,000 IU/liter/day, then falls rapidly after four months' gestation
+HCG Levels
May function to regulate steroid production in the fetus
+Contributes to nausea and common early signs of pregnancy 
+Basis of serum (blood) and urine testing 
+Amount increased in multiple pregnancies
+Amount decreased (or decreases) in threatened abortion
+Greatest value in diagnosis of trophoblastic disease (measured by the subunit hCG radioimmuno-assay-no cross reactions with LH
Prostiglandin

Widely distributed in all cells of the body and also produced by the placental/fetal unit

+Found in amniotic fluid, decidua, and maternal venous blood before labor
+Appears to be involved with the initiation of labor, and preparation of a woman's body for labor
+Anti-inflammatory drugs such as aspirin and indomethacin inhibit the synthesis of prostiglandins
+May have an effect on blood pressure
+May exert an oxytoxic effect on the uterine muscle
+Presently used IV, vaginally, or in amniocentesis for second trimester abortions
+Used for labor inductions: Cervical gel or systemic tablets
+May increase length of gestation
+Ongoing research about its impact and effects
Thyroxine

Produced in the thyroid gland with stimulation from the adeno-hypophysis

+Thyroid enlargement with a  20 % increase in function (from tissue hyperplasia and increased vascularity)
+T3 decreases until the end of the first trimester, then stabilizes and return to normal 12-13 weeks postpartum
+T4 increases during pregnancy
+BMR increased 25% resulting from metabolic activity of the feto-placental unit
+Protein bound iodine (PBI) increases from 3.6-8.8 to 10-12 units/dl during pregnancy
+Palpitations, tachycardia, emotional lability, heat intolerance, fatigue, perspiration
+May be involved with severe nausea and vomiting of pregnancy
Prolactin

Secreted by the Pituitary gland, and possibly by the fetal pituitary gland or trophoblastic tissue

Elevated blood levels appear at 8 weeks gestation and reaches a peak of 200 ng/ml at term Sustains milk protein, casein, fatty acids, lactose and volume of milk secretion during lactation
Human Placental Lactogen [HPL] or Human Chorionic somatomammotropin
Produced by the Placenta, syncytioptrophoblasts
Detected in the serum  of pregnant women at 6 weeks gestation and reaches 6000 ng/ml at term
Growth hormone-like action in pregnancy
+Anti-insulin effect
+Sparer of glucose and protein in the mother
+Maintains adequate supply of nutrients for the fetus when the mother is fasting
+Amount of HPL secreted correlates with fetal and placental weight
+May effect the increased incorporation of iron into erythrocyces
+Stimulates breast development, casein synthesis and promotes milk production
+Blood levels relate to placental function, which may provide basis of screening for potential complications
+More glucose is available for fetal use
+Increased protein synthesis
+Increased circulating fatty acids for increased metabolic needs (conservation of glucose and amino acids for use by the fetus)
+Inadequate maternal glucose intake results in ketosis, which may impair fetal brain development
+High levels of HPL are found in association with multiple pregnancies
+Serial HPL levels are used to help assess:
+Suspected SGA
+42 week pregnancies
+Chronic Hypertension

Resources and References

About Midwives: Additional Resources and References
http://home.comcast.net/~webmidwife1/
Beta HCG Levels 
http://www.childbirth.org/articles/pregnancy/betas.html
Belly Gallery 
http://pregnancy.about.com/health/pregnancy/library/belly/blbellyindex.htm
Birth Control and Fertility Awareness
http://home.comcast.net/~prebirthhealth/fertility_webs.htm
Encyclopedia Britannica On Line 
http://www.britannica.com/
Fertility Charting
http://home.comcast.net/~prebirthhealth/fertility_charting.htm
Fertility Cycles
http://home.comcast.net/~prebirthhealth/fertility_cycles.htm
Fertility Links
http://home.comcast.net/~prebirthhealth/fertility_webs.htm
Merck Manual On Line http://www.merck.com/
Normal Monthly Hormonal Cycle
Terms
BMR = Basic Metabolic Rate
LH = Leutenizing Hormone
SGA= Small for Gestational Age
Ultrasound Gallery http://pregnancy.about.com/health/pregnancy/library/ultrasounds/blusindex.htm

Creations Unlimited : Pat's Creations

Pat's Email: creationsunltd@comcast.net

About Midwives: http://home.comcast.net/~webmidwife1/
HypnoBirthing Resources: http://home.comcast.net/~hypnosisforbirth/
Handouts: http://home.comcast.net/~hypnosisforbirth/handouts.htm