Assessment of Age in Fetus
By Dr. Imran Sabri
Department of Forensic Medicine
J.N. Medical College, A.M.U. Aligarh
Date: 19th July 2004
Assessment of of age if Fetus is important in Cases of (Medico-legal Aspect) Criminal Abortion, Infanticide, Still-Born or Dead Born Baby, Fabricated Abortion, Marriage, Divorce, Adoption, Inheritance etc.
The Stages of development of Fetus are given below:
Ovum: First 7-10 Days after conception.
Embryo: 1st week to 2 months after conception.
Fetus: 2 months till completely born.
Neonate: 1st month after birth.
Infant : When completely born up to one year of age.
Rule of Haase: During the first five months of pregnancy the square root of the length gives the approx. age of the fetus in months. During last five months the length in centimeters is divided by five gives the age in months.
How to proceed for age determination of fetus in spotting?
Approx. Length of Fetus
Apply Haase Rule
Comment upon the following:
Length of the fetus to calculate the approximate age
Scalp Hair present or not and length
Eyes state of maturity
Eyelashes/Eyelids present or not.
Nails present or not/soft or thick/reached tip of finger or not.
Sex can be recognized or not.
Signs of Viability absent/present
Can comment on internal organs and on level of muconeum whether it is in Duodenum/ Large intestine.
State of Skin whether wrinkled or smooth
Write down the Medico-Legal Significance ( Very important for all spots)
For eg: 1. Still-born child
2. Criminal Abortion
4. Fabricated Abortion
You Will get good marks
Specific Features of a particular age :
At the end of First Month (Embryo)
Length is about 1 cm
Weight is about 2.5 gm
The Eyes are seen as dark spots
The Mouth seen as a cleft
At the end of Second Month
Length is about 4 cms
Weight is about 10 gm
The hands and feet are webbed
The Placenta begins to form
The Anus is seen as a dark spot
At the end of Third Month
Length is about 9 cms
Weight is about 30 gm
Eyes Closed and Pupillary Membrane appears
Nails starts appearing
Neck is formed
At the end of Fourth Month
Length is about 16 cms
Weight is about 120 gm
Sex can be recognized
Lanugo hair is seen over the body
Convolution begins to develop in brain
Meconeum is found in the duodenum
At the end of Fifth Month
Length is about 25 cm
Weight is about 400 gm
Nails are distinct and soft
light hair appears on head
Skin is covered with Vernix Caseosa
Meconeum is seen at the beginning of large intestine
At the end of Sixth Month
Length is about 30 cm
Weight is about 700 gm
Eyebrows and eyelashes appear
Skin is red and wrinkled. Subcutaneous fats begins to be deposited.
The testes are seen close to the Kidney
At the end of Seventh Month
Length is about 35 cm
Weight is about 900-1200 gm
Crown-rump length is about 23 cms
Foot length is about 8 cms
Nails are thick
Eyelids open and pupillary membrane disappears
Skin is dusky red, thick and fibrous
Muconeum is found in the entire large intestine
Testes are found at the external inguinal canal
Gallbladder contains bile
Caecum is seen in Right iliac fossa
Ossification centre is present in the Talus
At the end of Eight Month
Length is about 40 cm
Weight is about 1 Kg to 2.5 Kg
Nails reach to the tip of finger
Scalp hair is thicker
Left testis is present in the scrotum
Placenta weight is around 500 gm
At the end of Ninth Month
Length is about 45 cm
Weight is about 2.5 Kg to 3 Kg
Scalp hair is dark and 4cms long
Meconeum is seen at the end of large intestine
Ossification center are usually present in the lower end of femur, in Cuboid and Capitate bone.