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

Changes in uterine size over duration of pregnancy:

III. ComplicationsA. PIH – pregnancy induced hypertension

B. Gestational diabetes

C. Ectopic pregnancy – implants outside uterine cavity (1/100 pregnancies)

C. Spontaneous abortion (miscarriage) 1/6 pregnancies

D. Placenta previa

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

B. Childbirth Pain Relief Options

Systemic analgesics Regional Blocks Non-drug relief options