Clinical Chemistry week 6 part 2

What is the length of a normal pregnancy?

40 weeks

When is the first trimester?

first 12 weeks

WHen is the second trimester?

13th-26th week

When is the 3rd trimester?

27th to delivery of the newborn

Ovulation

mature and healthy ovum must be released from the ovary into the fallopian tube to begin conception

Zygote

when anovum has been fertilized in the fallopian tube by a sperm cell

What begins implantation into the uterine wall?

50-60 cells are created through meiosis, zygote forms cavity that becomes the primitive yolk sac, cluster of cells becomes a blastocyst

Placenta

functional interface between mother and fetus that secretes hormones and growth factors into the mother with physiological effects

Embryo

cluster of cells after implantation

Roles of the placenta

• provides nutrition and oxygen

• secretes hormones to maintain pregnancy

• produces hormones and steroids needed for transformation of the female body to support the pregnancy

• Becomes attached by week 4 gestation

What hormone increases steadily throughout pregnancy and decrease rapidly before labor?

progesterone

WHat hormone increases when progesterone decreases?

Estrogen, allows for smooth muscle contraction

Oxytocin

hormone that triggers maternal nursing behavior and induces labor

How is plasma volume affected by pregnancy?

Plasma volumes increases by 50-80%, ECV increases by 30-50%

How is plasma osmolality affected?

decreased by 10 mOsm/kg