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  #1  
Old 02-27-2012
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Calculator Calculating the Expected Date of Delivery!

A 31-year-old woman, gravida 4, para 2, abortus 1, was seen at the outpatient clinic with a chief complaint of missing her menstrual period. She had been using barrier methods of contraception. Her most recent pregnancy ended in a spontaneous first trimester loss requiring dilation and curettage. Her two previous successful pregnancies were unremarkable, resulting in spontaneous-onset labor at term, followed by uncomplicated spontaneous vaginal deliveries of healthy neonates who are alive and well. Her last menstrual period was June 10. A qualitative serum -human chorionic gonadotropin (hCG) test had positive results. Assuming her usual cycle length is 32 days, which of the following is her most likely due date?
(A) March 12
(B) March 17
(C) March 21
(D) November 13
(E) November 17
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Old 02-27-2012
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its march 17...u add 9 mons n 7 days to last date..
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Old 02-27-2012
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(B) March 17
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Old 02-27-2012
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thats the catch.

guys, its wrong. -3m+7d goes if month is 28 days long. i did that too and wondered how tricky usmle can be.
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  #5  
Old 02-27-2012
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21st of march ''c''. Add the extra 4 days (i.e,32-28) to your calculation...It will give you march 21.

Last edited by Josh George; 02-27-2012 at 08:00 AM.
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  #6  
Old 02-27-2012
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Quote:
Originally Posted by tyagee View Post
thats the catch.

guys, its wrong. -3m+7d goes if month is 28 days long. i did that too and wondered how tricky usmle can be.
You just add 4 days to the calculation (because 32 days instead of 28 days cycle).
So March 17 + 4 days = March 21
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Old 02-27-2012
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Quote:
Originally Posted by USMLEisnoteasy View Post
You just add 4 days to the calculation (because 32 days instead of 28 days cycle).
So March 17 + 4 days = March 21
can u explain it further...clearly...
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Old 02-27-2012
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Idea!

Quote:
Originally Posted by tyagee View Post
can u explain it further...clearly...
Actually it's not so hard also not too easy but just Math

Mostly based on 28 days cycle, add 9 months and 7 days to LMP
so got March 17 accordingly.
March 17 just use 28 day cycle.
The woman in the quest is 32 day cycle. So more 4 days longer.
That's why just add March 17 to 4 , finally got March 21 as the final answer and chose C.
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  #9  
Old 02-27-2012
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Default 17 march

its 17th march because 32 days is within normal range of menstrual cycle which is from 24-32 days and u just have to add 9 months and 7 days
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  #10  
Old 02-27-2012
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March 21 is the correct answer.
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  #11  
Old 02-27-2012
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(C) March 21
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  #12  
Old 02-28-2012
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Luteal phase of menstrual cycle is constant-14 days. So her follicular phase will be of 18 days and so the day of ovulation is delayed 4 days-so instead of 17 , answer will be 21st march.
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