1. Chapter 12 Conception, Pregnancy, and Childbirth

2. The Fertilization Process Ovum released from ovary, drifts to fallopian tube –Oocyte viable ~ 12 - 24 hours after ovulation –Sperm viable ~ 12 - 48 hours Capacitation: takes 6-8 hours –biochemical changes in sperm cell; release enzymes that allows it to penetrate egg’s outer membranes

3. Fertilization Process A single sperm is inside the oocyte cytoplasm –An electrical reaction prevents any other sperm from entering Oocyte swells –Detaches sperm that cling to outer layer Sperm and ovum nuclei release chromosomes –Chromosomes divide to form the diploid zygote containing 23 pairs of chromosomes –Fertilization is now complete

4. Development of the Conceptus Zygote undergoes cell divisions –Becomes a blastocyst of 100 cells after 4- 5 days –Blastocyst implants in uterine lining on 6 th or 7 th day Blastocyst becomes embryo after implantation in uterus Embryo is called a fetus after 8 th week

5. Pregnancy Detection –Test for human chorionic gonadotropin (HCG) –Blood analysis –Home pregnancy tests –Early physical signs Changes in cervix occur about 4 weeks after a missed period Hegar’s sign Labia change color, gaining purple hue

6. Changes in Women During Pregnancy Vary according to woman’s personality, feelings, and circumstances –Changes in relationships –Physical and emotional changes during each trimester Three trimesters—each 3 months long First trimester may include nausea, vomiting, fatigue

7. Complications of Pregnancy and Dangers to the Fetus Effects of teratogens –Substances that cause defects in embryonic and fetal development Infectious diseases –German Measles (rubella) –Group B streptococcus

8. Complications of Pregnancy and Dangers to the Fetus Sexually transmitted infections Can be transmitted from pregnant woman to fetus, newborn, or infant Chlamydia Gonorrhea Hepatitis B HIV Syphilis Genital herpes

9. Complications of Pregnancy and Dangers to the Fetus Pregnancy after age 35 –Is more common as women wait to have children –Increased likelihood of chromosomal variation –Risk increases with increasing maternal age

10. Complications in Pregnancy Ectopic pregnancy Pregnancy-induced hypertension Premature births Delayed labor

11. Diagnosing Abnormalities of the Fetus Ultrasound Amniocentesis Chorionic villus sampling (CVS) Alpha-fetoprotein (AFP) screening

12. Ultrasound High frequency sound waves determine size and position of fetus Sonogram—picture Estimates fetal age, guides during amniocentesis, checks for physical birth defects, evaluates complications during pregnancy

13. Amniocentesis Amniotic fluid is withdrawn with needle inserted through abdominal wall Detects: fetal abnormalities; Down’s syndrome, Turner’s syndrome, cystic fibrosis, spina bifida, sex and age 0.5-2% chance of fetal death

14. Chorionic Villus Sampling (CVS) Thin catheter inserted through abdomen or cervix into uterus and some chorionic villi are sucked into tube Detects: fetal abnormalities Performed 9-11 weeks

15. Alpha-fetoprotein Screening Test run on mother’s blood After 16 weeks of pregnancy Detects: defects of spine, spinal cord, skull and brain

16. Pregnancy Loss Early pregnancy loss Miscarriage Infant mortality Coping with loss

17. Infertility The inability to conceive a child after a year of unprotected intercourse or the inability to carry a child to term Fertility issues are equally distributed among men and women 1% of children in U.S. are the product of assisted fertility

18. Female Infertility Physical causes –Pelvic Inflammatory Disease, an infection of the fallopian tubes or uterus –Approximately 20% Hormonal & psychological causes –Hormone release may be atypical –Stress, anxiety, allergy –Approximately 20% Environmental factors

19. Male Infertility Low sperm count Decrease of sperm motility Misshapen sperm Sperm duct blockage Ejaculatory difficulties Environmental factors Men’s fertility begins dwindling after age 27

20. Infertility Treatment Enhancing fertility –Selective timing of sexual activity –Man wears boxer underwear –Woman lies with her back elevated following internal ejaculation

21. Medical Intervention Fertility medications Surgery Artificial insemination

22. Assisted Reproductive Technology In vitro fertilization - IVF Gamete intrafallopian transfer – GIFT Zygote intrafallopian transfer – ZIFT Surrogate motherhood Cloning Sex selection

23. Giving Birth: Labor and Delivery Relaxin released by the placenta Braxton Hick contractions

24. Labor Stages Stage 1: –Effacement: thinning of cervix –Dilation: opening up of cervix –Mucus plug is expelled –Amniotic sac ruptures –Contractions are regular and progressive –Transition

25. Labor and Delivery Stage 2 –Begins when baby’s head moves into birth canal –Ends when baby is born –Vernix: waxy substance which may cover baby Stage 3 –Afterbirth: placenta is expelled

26. Following birth Neonate Apgar score Lochia Joy

27. Choices in Childbirth Hospital birth Cesarean section Prepared childbirth Episiotomy Birthing rooms and centers Home birth Midwifery

28. Breast Feeding Colostrum Benefits –Bonding –Immune system of baby –HIV

29. Becoming a Parent Postpartum period Postpartum depression Postpartum psychosis Family Medical Leave Act

30. Summary Fertilization and fetal development Being pregnant Infertility Giving birth Becoming a parent