IVF and pre-natal diagnosis Flashcards
How does age affect embryo outcome in IVF?
Peak live-birth rate at age 30
Then decrease
What is the probability of achieving a live birth per menstrual cycle?
25% - 30%
What is the probability of pregnancy in normal couples?
80% in one year
90% in two years
What is primary infertility?
No previous pregnancy
What is secondary infertility?
Previous pregnancy
What causes female infertility?
- Endometriosis
- PCOS
- Tubal damage
- Ovulatory failure
- Uterus abnormalities
- Urogenital infection
- Endocrine disturbances
What is oligoasthenoteratospermia?
OATS
- Low number of sperm
- Poor motility
- Abnormal sperm morphology
Which drugs are used in IVF?
- GnRH agonists
- Gonadotrophins
- rhCG
- Crinone/cyclogest/utrogestan
What is the role of GnRH agonists in IVF?
- Pituitary down-regulation
2. Shut down hypothalamic-gonadotrophin axis
What is the role of gonadotrophins in IVF?
- Ovarian stimulation
2. Induce multifollicular growth
What is the role of rhCG in IVF?
Trigger to induce final oocyte maturation
What is the role of crinone/cyclogest/utrogestan?
Luteal support
Progesterone to ensure endometrial receptivity for implantation of embryo
How are oocytes collected?
Vaginal ultrasound
How are oocytes prepared for intracytoplasmic sperm injection?
Treated with hyaluronidase to remove surrounding cells
What are the major risks of artificial reproduction technology?
- Ovarian hyperstimulation syndrome
- Multiple pregnancy
- Drug side-effects
- Psychological impacts of infertility
How are open neural tube defects detected?
Maternal serum alpha-fetoprotein levels
How can risk of neural tube defects be reduced?
Increasing dietary folic acid
What are the three viable chromosomal trisomies?
13, 18 and 21
What is Edward syndrome?
Trisomy 18
90% die within one year
What is Patau syndrome?
Trisomy 13
85% die within one year
What is nuchal translucency?
Collection of fluid behind fetal neck
What is increased nuchal translucency seen in?
- Trisomy 21
- Congenital heart disease
- Fetal anaemia
- Congenital infection
- Abnormal development of lymphatic system
- Venous congestion
When is chorionic villus sampling performed?
11 weeks
How fast is CVS chromosome analysis?
24 hours
No need for culturing
When is amniocentesis performed?
16 weeks
How fast is amniocentesis analysis?
2 week culture
What are the advantages of chorionic villus sampling?
- Earlier diagnosis
What are the disadvantages of chorionic villus sampling?
- Higher risk of miscarriages (1-2%)
- Extra-embryonic tissue
- Possibility of confined placental mosaicism
What are the advantages of amniocentesis analysis?
- Fetal material
2. Lower risk of miscarriage (0.5%)
What are the disadvantages of amniocentesis?
Later analysis
