When Egg Meets Sperm…

Life Spans

Unfertilized egg can only live for 24 hours

Sperm usually live for 48 hours (can live up to 7 days) in a women’s body

Fertilization

The fusion of a sperm and eggMillions of Sperm are released in the vagina

move up uterus & to the fallopian tubes

if there is an egg, fertilization occurs

ONLY 1 sperm can fertilize an egg! Once this occurs, a protective shield forms

(fertilization envelope) around the eggFertilized egg = Zygote

What’s Next?

Zygote divides into many cells moves into uterus

Ball of cells = blastocyst

Cells travel for 7-8 days

Attach to uterine lining & continue developing Called implantation

The Pathway

Implantation

Occurs when the embryo attaches to the wall of the uterus

Some women can feel this occur (feel light cramps)

Causes a hormone called hcG to be released Supports pregnancy what pregnancy tests use

After implantation: Pregnancy

Membranes develop around the embryo to protect & nourish it = placenta

More on pregnancy…

Umbilical cord: connects embryo to mom Transports oxygen & nutrients to embryo Removes waste products

At 8 weeks, embryo is called a fetus

Pregnancy lasts about 266 days 40 weeks or 9 months

Giving Birth

Oxytocin (hormone) triggers uterine wall to contract

Labor beginsCervix expandsBaby starts to emerge, head first cut cord

Cord will dry up/fall off becomes your belly buttonPlacenta must be delivered after baby

Miscarriages

Spontaneous end of a pregnancy Occurs when a fetus can NOT survive out of the womb

Types: Embryo stops growing very early no fetus forms Fetal heartbeat has stopped fetus has died

Causes: Genetic Uterine abnormalities, hormonal abnormalities Reproductive tract infections Tissue rejection

Risk Factors: diabetes, smoking, drugs, fertility issues, etc

Stillbirth

Baby has died during delivery or prior to birth

Causes: (many) Umbilical cord Diabetes Trauma Drugs, smoking Birth defects infections

Ectopic Pregnancies

Implantation occurs outside the uterus in: In fallopian tube *most common 95%* Cervix Abdomen Ovary

Pregnancy has to be terminatedSymptoms similar to pregnancy

Additional symptoms: bleeding, lower back pain, low blood pressure, dizziness, sharp stabbing pain in back/neck

Infertility

Inability to conceive Can be female or male

Options: Fertility drugs: side effects include multiples IVF (invitro fertilization): fertilization happens outside

the body Very expensive, possible multiples

Egg Donors/Sperm Donors Expensive, invasive for egg donors Would you want it?

Adoption Can be expensive, heartbreaking, and joyful

Why do Birth Control Pills Work?

Estrogen & progesterone pills fool your body into thinking you are pregnant Hence, you don’t ovulate (or shouldn’t), FSH & LH

stay low Effectiveness also depends on following directions