Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.

Remove ads
Don't know
Know
remaining cards
Save
0:01
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards




share
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Chapter 12

Reproductive Endocrinology and Fetal testing

QuestionAnswer
A typical uncomplicated pregnancy lasts 40 weeks calculated from the last menstrual period (LMP)
About ten weeks after LMP the embryo contains most of the organs and is referred to as a fetus.
The placenta produces several hormones that help sustain the pregnancy, HCG is one of the hormones and used to determine pregnancy in the laboratory.
HCG triggers the corpus luteum to produce progesterone and estrogen.
HCG helps maintain the uterine lining, the endometrium with an adequate blood supply until placental production of progesterone begins.
Initially HCG levels raise exponentially more than doubling each week during the first weeks of a normal pregnancy.
The detection level for pregnancy is usually set at 10 U/L a lot of labs will use 0-5 as negative and 5-10 as gray zone with a comment to repeat testing in a few days.
Initially HCG levels raise exponentially more than doubling each week during the first weeks of a normal pregnancy.
The detection level for pregnancy is usually set at 10 U/L a lot of labs will use 0-5 as negative and 5-10 as gray zone with a comment to repeat testing in a few days.
Qualitative can usually be done on BOTH serum and urine. Quantitative are ONLY performed on serum, not urine.
Qualitative can usually be done on BOTH serum and urine. Quantitative are ONLY performed on serum, not urine.
HCG levels are always used in conjunction with history, physical examination and ultrasound to detect pregnancy complications, or miscarriage.
Falling HCG levels may signal fetal demise.
Multiple fetus’s can cause higher values of HCG than a single fetus, ultrasound can help distinguish this.
A decrease in progesterone levels can lead to miscarriage.
The occurrence of down syndrome and open neural tube defects are frequent enough to warrant prenatal testing for these disorders.
The tests usually included in this screening are: alpha fetoprotein (AFP), Estriol, and HCG. This is referred to as a triple screen.
It takes in to account mothers age, diabetes status, number of fetus’s, weight and the lab values for all of these tests to predict the chance the fetus has either down syndrome, trisomy 18 or a neural tube defect.
Some of the more ubiquitous tests are: Phenylketonuria (PKU), Galactosemia, Tyrosemia, Homocysteinuria, sickle cell, and branched chain amino acid disorders. (Including Maple syrup urine disease (MSUD)These tests are performed on filter paper that is soaked with blood from the babies heel, 24 – 48 hours after birth and tested at the state lab.
It should be noted that Neonates, Babies, Children and adolescents can all have separate reference ranges for some testing.
Due to these being small dynamic age groups only practices that focus specifically on certain groups have reference ranges for them.
Some chemistry testing may be performed on amniotic fluid. This is rare as this testing is invasive and only done as a last resort.
Testing for amniotic fluid may be done for fetal lung maturity testing.
Remember that surfactants coat the inside of the alveoli normally and prevent them from collapsing when air is expelled.
In the mature fetus the pulmonary surfactant is rich in a compound called phosphatidylcholine (lecithin) and phophatidylglycerol (PG) these substances may be measured quantitatively by themselves or in a ratio to another lipid sphingomyelin that is relatively constant.
This is termed an L/S ratio, and a ratio of greater than 2 to 1 would indicate mature lungs
Lamellar bodies are a storage form of surfactant and are similar in size to normal platelets. These can be done on any cell counter but must be verified and getting enough samples to do the verification is hard.
Predictive value of negative result = TN/(TN+FN) x 100
Predictive value of positive result = TP/(TP+FP) X 100
Predictive value of positive result = TP/(TP+FP) X 100
False negative rate = 100% - %sensitivity
True-neg rate = diag specificity = TN/(TN +FP) X 100
True-Pos rate = diag sensitivity = TP/(TP + FN) X 100
Created by: Mgoodall