Typical variable deceleration has the following characteristics
1. Shouldering
Accelertion before and after deceleration
2. Sharp drop and sharp rise back to the baseline- v sign
3. Continued variability in the trough
4. Usually but not necessarily coinciding with contraction.
Natural birth prevalence of Down's syndrome increased with Maternal age;
Under 25- 1 in 1500
At 30- 1 in 1000
At 40- 1 in 100.
Second trimester screening
( between 15 and 22 weeks )
1. Double test
Total hCG or free beta hCG + MSAFP ( Maternal serum alpha fetoprotein) + Maternal age
Detection rate 60%
False positive rate 5%
2. Triple test
Double test + uE3 (unconjugated estriol)
Detection rate 68%
False positive rate 5%
3. Quadruple test
Triple test + inhibin A
Detection rate 76%
False positive rate 5%
First trimester screening
(8-14 weeks)
1. Biochemical
beta hCG + PAPP-A + Maternal age
Detection rate 62%
False positive rate 5%
2. USG + Maternal age
NT (nuchal translucency )
Detection rate 77%
False positive rate 5%
3. BC + USG + Maternal age
Detection rate 90%
False positive rate 5%
Integrated test
( First trimester NT, PAPPA + Second trimester beta hCG, uE3, MSAFP)
Detection rate 95%
False positive rate 5%
1. LLETZ
Remove the transformation zone using an electrodiathermy loop
Require LA or GA
2. Laser cone
Removal of transformation zone using the Laser
Require LA or GA
3. Knife cone biopsy
Taking a cone with Knife
require GA
4. Hysterectomy
Ablative techniques
1. Radical electrodiathermy- burning the transformation zone; Usually requires GA
2. Cold coagulation- destroying the transformation zone by applying a probe heated up to 100-120 degree celcius; Usually require LA
3. Cryocautery-freezing the tissue; does not require any anaesthesia
4. Laser- vaporizing the tissue; require LA or GA
1. Three smears showing boderline nuclear changes in squamous cells
2. One smear showing boderline nuclear changes in endocervical cells
3. One or two smears showing mild dyskaryosis
4. One smear showing moderate or severe dyskaryosis
5. One smear showing Possible invasion
6. One smear showing glandular neoplasia
7. Three consecutive inadequate smears
8. Any grade of dyskaryosis following treatment for CIN before return to routine recall
9. There abnormal smears of any grade over a 10 year period
10. Suspicious symptom and abnormal cervix
1. Loss of normal hypoechoic rim of myometrial tissue beneath the placenta
2. Loss of normal hyperechoic uterine serosa-bladder wall interface
3. Presence of tissue of placenta echotexture extending beyond the uterine serosa, sometimes seen within the lumen of bladder
4. Sometimes multiple or large placental venous lakes are seen, giving the placenta moth-eaten appearance
Regular oscillation of the baseline Heart rate (long term variability) resembling a sine wave.
Smooth undulating pattern lasting at least 10 minutes.
Relatively fixed period of 3-5 cycles per minutes.
Amplitude 5-15 bpm above and below the baseline.
Baseline variability absent.
Fetal heart rate is controlled by the rhythmicity of the fetal heart, the central nervous system, and the autonomic nervous system.
FHR is increased in sympathetic response and decreased by para sympathetic response.
Usually there is a balanced increase of sympathetic and para sympathetic response occured during contraction with no observable change in baseline.
Baseline HR is reassuring at 110-160 bpm, non-reassuring at 100-109 and 161-180. It becomes abnormal when the rate is less than 100 bpm, greater than 180 bpm and sinusoidal pattern >=10 minutes.
Possible causes of baseline bradycardia
Late fetal hypoxemia
Adrenergic blocking drugs such as propanolol
Prolonged umbilical cord compression
Maternal hypotension
Maternal hypothermia
Prolonged Maternal hypoglycaemia
Possible causes of baseline tachycardia
Early fetal hypoxemia
parasympatholytic drugs such as atropine
sympatho mimetic drugs such as ritodrine
chorioamnionitis
Fetal anaemia, heart failure and cardiac dysrhythmia
Maternal fever
Maternal hyperthyroidism
Maternal use of recreational drugs such as cocaine and methamphetamine
