1. BASIC TERMS AND
CONCEPTS IN
OBSTETRICS
Dr Farzana Kazmi
Assistant Professor
DHQ Teaching Hospital Rawalpindi

2. Calculation of EDD :
Naegle’s Rule
Add 7 days and 9 months /
Add 7 days and subtract 3 months in LMP
Total Gestation:
Forty weeks
280 days
Viability: The ability of fetus to survive in the
extra uterine environment
after 20 , 24, 28 weeks of gestation or
weight > 500 grams

3. 



Term: After complete 36 weeks
till complete 41 weeks of
gestation
Preterm: Before complete 36 weeks
Postdate: After EDD or complete 39
weeks till complete 41
weeks
Postterm After complete 41 weeks

4. Estimation of birth weight
Low birth weight: ( LBW):
Babies who born weighing less than
2,500 grams
Very low birth weight:
Babies who are born weighing less
than 1,500 grams
(3 pounds, 4 ounces).

5. Birth weight chart

6. ATTITUDE OF FETUS

Relation of various fetal parts to
other parts. Normally all joints flexed

7. Lie of fetus

Relationship of long axis of fetus to
the long axis of mother
Longitudinal
Transverse
Oblique /

8. PRESENTATION OF FETUS

Presenting part
Portion of fetus that is presenting
against the cervix
Pelvic grip
Paw like grip

9. Presentation

Vertex
Breech
Brow
Face
Shoulder

10. ENGAGEMENT
When widest part of presenting part
has passed successfully through the
inlet

11. ENGAGEMENT OF FETAL HEAD

12. STATION OF FETAL HEAD

The level of the lowest fetal bony part
in relation to imaginary line joining the
mother’s ischeal spines

13. POSITION OF FETAL HEAD


The relationship of fetal skull to
maternal pelvis
Bony land marks

14. POSITIONS OF FETAL HEAD