HEA 201 Chapter 7, Fall 2007

Reproductive Choices 1. Male Reproductive System 2. Female Reproductive System & Menstrual Cycle 3. Conception  Sex cell characteristics - An (unfertilized) ovum can live up to 36 hours - Ejaculate may contain up to 500 million sperm cells - Sperm cells can survive in the ♀ tract for 5 days, sometimes more  Sequence of events - During intercourse: sperm cells are released in vagina - Travel up  uterus  fallopian tubes - If egg in the tube: egg + 1 sperm can fuse: fertilization  zygote in fallopian tube - Zygote travels down the fallopian tube while dividing - In uterus: zygote burrows into the uterine wall: implantation  Development of fertilized egg: - Zygote  embryo (when nested in uterine wall)  fetus (after 9 w) - Structures that support embryo/fetus during development: .placenta: structure in uterus for exchange btw fetus/mother blood .umbilical cord: connects fetus to placenta .amnion: sac filled with amniotic fluid, that surrounds the fetus 4. Birth Control Methods  Can prevent ovulation meeting between egg & sperm implantation  Can be temporary or permanent  Choice of method - According to situation/beliefs/habits/risks… - Some provide protection against STDs Method Mode of action Advantages Disadvantages ABSTINENCE OUTERCOURSE No sexual activity No vaginal intercourse No medical side effects Risk of unplanned intercourse HORMONE-BASED CONTRACEPTIVES PILLS contain estrogen and/or progestin ingested daily IMPLANT capsule under skin of upper arm kept for at least 3 years releases low & continuous progestin PATCH, INJECTION, VAGINAL RING Different mechanisms inhibit ovulation alter cervical mucus (thickens it) alter uterus lining ( no implantation) Very effective No interruption of sexual activity Reduced menstrual cramps More regular periods  risk of ovarian & uterine cancer Highly effective No interruption of sexual activity No need to remember to use it No estrogen-related side-effects Requires prior medical examination & follow up Has to be taken daily Possible side effects (mostly due to estrogen):  risk of cardiovascular disease (esp. if smokers, > 35 years, hypertension) weight change, nausea, vomiting, mood changes… Requires medical intervention Possible side effects menstrual irregularities, amenorrhea ovarian cysts, breast discharge headaches, acne, hair growth BARRIER CONTRACEPTIVES ♂CONDOM (latex or PU) ♀ CONDOM (PU) DIAPHRAGM & CERVICAL CAP should be used with spermicides Prevents egg & sperm meeting Covers penis & catches the semen Lines the walls of the vagina Rubber cups that cover cervix Kept for min 6 hours after intercourse No prescription needed No harmful side effects Some protection from STDs No harmful side effects Placed prior to sexual experience Interruption of sexual experience May have defects, break or slip off Sometimes allergy to latex Need practice for correct use (for comfort/efficiency) Sometimes allergy to latex SPERMICIDES foams, creams, jellies, films… Chemicals that kill sperm cells Better if used with barrier contraceptives No prescription needed  STDs (with barrier contraceptives) Interruption of sexual experience Skin irritation for some, messy INTRAUTERINE DEVICE (IUD) T-shaped piece inserted in uterus for many years Interferes with implantation Very effective No interruption of sexual activity Should be inserted by a physician Risk of scarring & infertility May be expelled STERILIZATION ♂: VASECTOMY ♀: TUBAL LIGATION/OCCLUSION Cutting/tying vas deferens Cutting/tying, blocking fallopian tubes Highly effective Permanent Not easy to reverse for fertility Surgical procedure  pain, bleeding, complications FERTILITY AWARENESS METHODS CERVICAL MUCUS METHOD CALENDAR (RHYTHM) METHOD BASAL BODY TEMPERATURE Intercourse during infertile days only days of dryness or sticky mucus days outside [shortest -18 / longest -11] after 3 days of  in body tº till cycle end Acceptable to Catholic Church No medical side effects No expenses Uncertainty of safe times Periods of abstinence or use of other methods WITHDRAWAL (Coitus interruptus) Removal of penis from vagina before ejaculation No medical side effects No expenses Interruption of intercourse Not reliable: drops emitted before ejaculation Difficulty to know when to withdraw EMERGENCY METHODS (after-intercourse) MORNING AFTER PILL (within 72 hours) ABORTION PILL (within 9 weeks) IUD INSERTION (within 5 days) MENSTRUAL EXTRACTION OR CURETTAGE High dose of oral contraceptives Prevents ovulation or implantation Blocks the action of progesterone Prevents implantation Suctions or scrapes out uterine content Recommended in cases such as rape incest broken or slipped off condom Require medical supervision/intervention Side effects: discomfort, cramps, infections… Pills Implants Male Codom Female Condom Cervical Cap / Diaphragm Vaginal Spermicides Intra Uterine Device Tubal Ligation Fertility Awareness Method: basal body temperature 5. Pregnancy  Preconception care - Crucial for full-size, full-term, healthy infant - Risks smoking drinking alcohol using drugs overweight/underweight suffering from unrecognized infections and illnesses exposure to environmental toxins  Prenatal care Nutrition - Well-balanced diet throughout pregnancy (no dieting) - Drinking plenty of fluids (water, fruit & vegetable juices, milk) - Folate to  risk of neural tube defects (abnormal spinal column) - Appropriate weight gain, in relation with pre-pregnancy weight Exercise - Regular & moderate (walking, swimming…) - Not pushing too hard (avoiding water-skiing, surfing, horse-riding) - Stretching carefully because joints & connective tissue softer & looser - Being aware of warning signs: faintness, dizziness, pain, bleeding Substance use - Smoking active & passive smoking hazardous increases risk of miscarriage premature birth, low birth weight, stillbirth - Alcohol effects proportional to dose mild case: fetal alcohol effect (FAE) impaired intellectual ability & school performance severe case: fetal alcohol syndrome (FAS) low birth weight & permanent mental impairment - Drugs: increase risk of malformations premature birth low birth weight, stillbirth - Medications: necessity to consult a physician - Caffeine: effects proportional to dose Environmental risks - Heat (hot tub, sauna, fever) in 1st trimester:  risk of neural tube defects - Radiation high levels for cancer therapy linked to birth defects X rays: avoid although not significant threat - Fetus in theory vulnerable to pollutants, metals, toxins, gases, pesticides…  Prenatal testing: for identification of defects - Ultrasonography (no known risk) use of sound waves to produce an image of the fetus on a video screen - Amniocentesis (1% risk of miscarriage) recommended if mother > 35 y, or known carrier of genetic disorder removing some amniotic fluid (contains cells shed by the fetus) culturing cells  checking for chromosomal defects - Chorionic villi sampling (1% risk of miscarriage) suctioning a small sample of fetal placental tissue analysis for chromosomal defects can be performed than amniocentesis Complications - Ectopic pregnancy: zygote remains in fallopian tube possible causes: some STDs, use of IUD symptoms include:bleeding, lower abdominal pain treatment: surgical can lead to permanent infertility (irreversible fallopian tube damage) - Miscarriage: spontaneous abortion emotionally devastating causes: genetic, anatomic, hormonal, infectious, autoimmune  Pregnancy and age: Above 35:  risk of birth defects due to chromosome abnormalities (e.g. Down syndrome)  Infections: major ones Rubella leads to birth defects women should be vaccinated at least 3 months prior to conception HIV transmissible to baby during pregnancy, at birth or during lactation Toxoplasmosis transmitted by pets (cats) or by consumption of undercooked meat effects on fetus: brain and retina damage, death 6. Infertility  Failure to conceive after 1 year of unprotected intercourse in young couples  Male - Linked to sperm quality (inactive, misshapen) or quantity (< 20.106/ml) - Common causes genetic hormonal blockage of a sperm duct varicocele (enlarged vein  too much blood  testicle too warm)  Female - Common causes age genetic hormonal blocked fallopian tubes immune reaction to a man’s sperm uterine defects cervical mucus problems  Assisted reproductive technology - Infertility treatments include microsurgery (e.g. to open blocked ducts) hormonal treatments - Artificial insemination (when ♂ is infertile) introduction of sperm (from sperm bank) into vagina by artificial means - In vitro fertilization (e.g. when ♀ has damaged fallopian tubes) removal of egg from ovary just before ovulation egg and sperm placed in vial  fusion occurs in vitro few division steps embryos inserted in uterus  development continues extra embryos can be frozen for later implantation - Gestational surrogacy (when ♀ cannot maintain pregnancy) embryo conceived in vitro implanted in another ♀ uterus (hormonally treated  ready for gestation)