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Reproduction (Pregnancy & Delivery)I. Fertilization & Development
II. Signs and symptoms of pregnancy Complications
III. Nutrition, pre-natal care
IV. Labor & Delivery
I. Fertilization & DevelopmentA. Contact Acrosomal Reaction – upon contact with the
egg the sperm changes Fusion of sperm & egg triggers a signal-
transduction pathway, causing the release of Ca+ into the cytosol
Ca+ triggers the activation program (series of metabolic changes within egg)
Aerobic respiration increases, maternal proteins become active, major transcription/translation occurs
Egg nucleus completes meiosis
B. Cleavage
Zygote is Totipotent undergoes Cleavage = series of rapid mitotic divisions with no period of growth during each cell cycle (cell # increases, but not size)
2, 4, 16, 32… becoming a solid ball of blastomeres, called a morula that reaches the uterine cavity 72-80 hours post fertilization
Blastula = 64 to several hundred blastomeres
Day 5: enters uterus, zona pellucida is dissolved, blastocyst Outer layer of cells = trophoplast,
forms chorion & amnion Inner cell mass – gives rise to the
embryo Day 7: implantation begins,
trophoblast cells in contact w/endometrium secrete enzymes that erode an area large enough for the tiny embryo Embryo works its way into
connective & vascular tissues, all further development takes place within the endometrium
At this stage, the inner cell mass consists of 50 cells, some of which will become the fetus, others the placenta
C. Extraembryonic Membranes Chorion – develops into fetal half of placenta Yolk sac – first site of blood cell formation Allantois – blood vessels become umbilical blood
vessels Amnion – contains fluids to cushion & protect embryo
D. Placenta – connection to mom Develops from the chorion & the uterine tissue,
acts as a transfer vehicle & synthesis center Placental provides nutrients and oxygen for fetus
via diffusion across the placental barrier into the bloodstream of the fetus & removes wastes which mom excretes
Acts as an endocrine organ, secreting estrogens and progesterone to maintain pregnancy
umbilical cord develops & connects the embryo to the placenta
Produces human chorionic gonadotropin (hCG)
5.5 weeks:
After 1st two months: Embryo is a FetusAll organs continue to developMuscles develop, embryo can moveBrain begins regulating function of some organs
http://media.health.discovery.com/centers/pregnancy/video/video.html
Terms & definitions Embryo – Fetus – Pregnancy divided into trimesters:
First trimester – Second trimester – Third trimester –
Previable – infant delivered prior to 24 weeks Preterm – Term –
II. Signs of pregnancyA. SymptomsFor a woman who has regular menstrual cycles and is sexuallyactive, a period delayed by more than a few days to a week issuggestive of pregnancy
“morning sickness” – nausea and vomiting Breast swelling and tenderness, fatigue BBT of 98.8 – 99.8 for 3 weeks post ovulation OTC urine pregnancy tests & hospital serum assays tests for the beta
subunit of hCG Confirmation by ultrasound which may show the gestational sac as
early as 5 weeks Cervical & uterine changes Due date calculation (Nagle’s rule) = subtract 3 months from the LMP
and add 7 days If ovulation date is known, the date can be calculated by
adding 266 days
Sign of PregnancyTime of Appearance
Other possible causes
Delay of period2 weeks post-ovulation Stress, low body fat
Nausea/Vomiting2-8 weeks post conception
Food poisoning, stress, other illness
Tender/swollen breasts1-2 weeks post conception
Hormonal imbalance, birth control pills, impending period
Feeling exhausted1-6 weeks post conception
Stress, depression, common cold/flu
Backaches entire pregnancy physical strain, stress
Frequent headaches entire pregnancystress, dehydration, cold/flu
Food cravings entire pregnancy
poor diet, stress, depression, impending period
Darkening of Areola entire pregnancy hormonal imbalance
Frequent Urination6-8 weeks post conception diabetes, UTI
B. Maternal changes during pregnancyProfound and multiple physiological adjustments
occur Cardiovascular – Pulmonary – Gastrointestinal – Nausea & vomiting occur in >
70% of all pregnancies.
Renal – kidneys increase and ureters dilate increasing urinary frequency, edema occurs in 25% of pregnant women
Hematology – plasma volume increases by 50%, hypercoagulability
Musculoskeletal
Dermatologic – spider angiomata, hyperpigmentation of nipples, stretch marks
III. ComplicationsA. PIH – pregnancy induced hypertension
B. Gestational diabetes
C. Ectopic pregnancy – implants outside uterine cavity (1/100 pregnancies)
IV. Nutrition & prenatal careBUILDING A BABY!!! Vitamins & Minerals,
supplements & food Protein Iron Folic Acid What to avoid…
Tobacco Alcohol/drugs Caffeine OTC drugs
Excessive weight gain (40-50 lb)
V. Labor and DeliveryA. Labor = contractions that cause cervical change in
either effacement or dilation “false labor” = irregular contractions that yield little or no
cervical change Stages
Cervical examination
Labor may be induced via prostaglandins, oxytocic agents, mechanical dilation or artificial rupture of membranes