..Children, Family & Parenting 
No Comments How do doctors know when babies are due to be born?
Kids ASK! about Family & Parenting
In medical terms, pregnancy lasts for 38 to 42 weeks from a woman’s last menstruation date. In other words, it takes 38 – 42 weeks for the baby to be fully developed in his/her mother’s womb.
Doctors usually calculate the expected date of birth by adding 280 to the date of the first day of the last menstruation.
Usually, at the end of the 38 – 42 weeks, when the baby is ready to be born, hormones in the woman’s blood send a message to her uterus (the place where the baby grows in his/her mother’s tummy) saying it is time for the baby’s birth.
This message causes the uterus muscles to tighten and squeeze. This is called a contraction. When the contractions are stronger and occur quickly and often, the baby is most ready to be born.
Source:
Human reproduction and development / Adolfo Cassan
Philadelphia, Pa. : Chelsea House Publishers, 2006.
Call No.: J English 612.6 CAS
Click here for item availability.
Some recommended books relating to the subject:
Reproduction and growth / Michaela Miller.
Detroit, Mich. : KidHaven Press, c2005.
Call No.: J English 612.6 MIL
Click here for item availability.
Life cycle : birth, growth, and development / Patricia Macnair
Boston, Mass. : Kingfisher, 2004.
Call No.: J English 612.6 MAC
Click here for item availability.
Life story : birth, growth and development / Patricia Macnair
London : Kingfisher, 2004.
Call No.: J English 612.6 MAC
Click here for item availability.
Answered by Ms Siti Nadiah Sahul Hameed, Librarian, Children’s Services
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