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Human Reproduction Puberty Sexual Behavior Anatomy External Puberty Human Reproduction Female » 11 - 12 years » Influences –Nutrition –Economic status –Trends over last century Male » 13 - 14 years » Influences –Same as for female » Trends over the last century Animal Science 434 - John Parrish Anatomy Sexual Behavior Female Male External Genitalia Vaginal Environment Normally acidic Changes from medications, douches, lubricants » Infections –Yeast –Bacterial Lubricates Vagina before and during intercourse • Source of Pheromones • Dorm effect 1 Cervix Uterus Some think this is a sperm storage site in Normal is simplex human Abnormal Sperm survive up to 2 days » Bicornuate or septae uterus Increase in cervical mucous at time of –Early delivery or spontaneous abortion ovulation –Uterus can not enlarge enough » Response to increased estrogen levels » duplex Ovary Male Facts 400,000 oocytes at birth penis is muscular vascular Decrease with age Between 40 - 50 years of age enter menopause ejaculate is approx. 3 ml with 200 million sperm/ml. ejaculate coagulates upon ejaculation and then liquifies within 30 minutes Prostate Gland in Male Menopause Prostate gland hyperplasia Begins at 40 - 55 years of age » First growth at puberty No follicles left to grow » Second growth starts after age 25 » No estrogen - causes symptoms » Urinary symptoms don’t occur before age 40 Detection –50% of men at 60 have symptoms » Variable menstrual cycles –90% of men at 70 - 80 have symptoms » Behavior changes and physical changes » Symptoms » FSH increase –a hesitant, interrupted, weak stream –HMG (human menopausal gonadotropin) –urgency and leaking or dribbling Hormonal Replacement (estrogen and –more frequent urination, especially at night progesterone) » Treatment » Relieves behavioral and physical changes –5 alpha reductase inhibitors » Cadiovascular benefits???? –Minimal invasive procedures » Calcium uptake increases –Surgery 2 Anterior Andropause LH Pituitary FSH Hormones Decreased Testosterone Production » Reduced response to LH Progesterone Age, 48 -70 Ovarian Physical Changes Hormones Estradiol » Loss of muscle mass Ovulation Corpus » Shrinking reproductive organs - penis, testis, Follicle Corpus Luteum Albicans accessory glands Ovary » Loss of libido, increased stimulus needed for erection, longer refractory period Dominance Recruitment » Osteoporosis Uterine Selection Endo- Mental Changes metrium » depression 2 4 6 8 10 12 14 16 18 20 22 24 26 28 2 Anterior LH Basal Body Temperature Pituitary FSH Hormones e 98.8 s e Luteal Phase a s s s 98.6 a h e e Progesterone 98.4 P s s Ph r n Ovarian n 98.2 Estradiol l a e Hormones e l a 98 M u M e t c Ovulation 97.8 i u Follicl le Corpus Luteum l 97.6 L Ovary o 97.4 F 97.2 Luteal Phase 97 Ovulation Uterine 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 Endo- metrium Luteal Phase Remains Constant at 14 days 2 4 6 8 10 12 14 16 18 20 22 24 26 28 2 Basal Body Temperature Ovulatory Pain 98.8 Mittelschmerz (middle pain) 98.6 Day 12 - 16 after after start of menstration 98.4 Lasts 12 to 36 hours 98.2 98 97.8 97.6 97.4 97.2 97 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 Abnormal Cycle - No ovulation 3 Cumulative Pregnancy Rate Pregnancy 90 Most prolonged cycles are due to spontaneous 80 abortion 70 e 20% of pregnancies with early pregnancy test g 60 a t spontaneously abort n 50 e c 40 Numerous Problems r e 30 Time of intercourse - gamete aging P » 20 » Chromosomal abnormalities 10 0 1 6 12 Months Infertility Adequate Contact or Exposure - Problems Common definition Male » Primary Infertility » Hypospadias –Failure to conceive within 1 year if no previous –Urethra opens on bottom of penis pregnancy » Penis size not important unless both male and » Secondary infertility female obese. May be a problem in penetration –Failure to conceive within 6 months if at least one depth. previous normal pregnancy Exposure (needed near ovulation) » Assumption » Average is 2 to 3 times/week –Adequate sexual contact or exposure » Frequency decreases with length of relationship » Busy schedules –If intercourse only on weekends, unlikely to become pregnant –Delaying pregnancy into 30s increases problems Age Associated Problems Misconceptions and Considerations Male Coital position » Decreased fertility with age, but can occur into 70s » Does not matter Female Laying in bed for 30 minutes » Rare if over 50 » No scientific merit » 10% of women who have conceived can no longer Douching after intercourse will not work as a do so by age 35 contraceptive scheme » If over 36 and fail to get pregnant within 6 months Birth control pills should seek evaluation and therapy as time is short. » Long term exposure does not effect fertility » First cycle after going off pill, there is a sight increase of double ovulations Adoption - anxiety can effect ovulation 4 Female Infertility Stimulating Follicular Growth and Ovulation Failure of follicular development or ovulation Low dose estrogen Tubal blockages and ectopic pregnancies » Don’t produce enough estrogen for GnRH surge Spontaneous abortion HCG » Uterine or CL problems » Inadequate LH surge Clomaphine Citrate - antiestrogen » Hypothalamus precieves low estrogen so GnRH increases » FSH and LH increase stimulating follicular growth Pergonal (HMG - FSH activity) » Stimulates more follicular development Tubal Disease Male Infertility DES exposure Low sperm count Infections - blocked oviducts » Normal 200 million/ml, 2-3 ml » Pelvic inflamatory disease – Chlamydia, Gonorrhea, Strep. and Staph. bacteria, » Abnormal <20 million in ejaculate mycoplasma, tuberculosis –Treatment » Stop infection, tubual surgery or IVF Scrotal temperature control Ectopic pregnancies In vitro fertilization (IVF) » 1 in 90 - 120 Intracytoplasmic Sperm Injection (ICSI) » In DES exposure, 1 in 20 » Sperm or round spermatid » Dangerous!!! – Pain Abnormal sperm – Spotting or discharge from vagina » Treatment –Temperature control, IVF, ICSI Sterilization Birth Control Female Female » Tubal ligation » “The Pill” - progesterone + estrogen Male » Patches or vaginal Rings » Vasectomy » Long term progesterone Reversal are now possible in some cases » IUD » Spermacides 5 Birth Control Erythroblastosis Fetalis Male Isoimunization of mother with foreign red » Condom blood cell (RBC) antigens » New and in some countries » Human placenta is permeable to some proteins –Testosterone such as antibodies –GnRH agonist » The anti-red blood cell antibody crosses placenta and destroy fetal RBCs –Progesterone + Testosterone RBC antigens –5 alpha reductase insensitive testosterone » –RH factor –Stimulation of premature spermiation –Other minor RBC antigens Erythroblastosis Fetalis (cont.) Sexually Transmitted Diseases 6 0 0 0 0 0 0 Conditions for isoimmunization ) » s n o –Fetus must have foreign RBC antigen 5 0 0 0 0 0 0 i Curable Incurable l 5 l –Mother must be negative for this antigen i m ( –Fetomaternal hemorrhage occurs at birth or 4 4 0 0 0 0 0 0 S spontaneous abortion (miscarriage) U n i 3 0 0 0 0 0 0 From 0.1 to 30 ml of fetal blood enters maternal 3 circulation s e s a Treatment 2 0 0 0 0 0 0 C 2 l » Test at first prenatal visit for Rh antibodies a u 1 0 0 0 0 0 0 » If RH negative and Father Rh positive or unkown n 1 n –Retest at 28 weeks (don’t see isoimmunization A 0 before this time) a s a s s i B S i e t d D il e r Administer Rh-immune globulin s I h p a y i h r r t A r m i p e W t o a y l At birth if fetus Rh-positive also give it Rh-immune a n H p S h o e C globulin H G 6.
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