Thursday, August 13, 2015

How I Determine Marriages & Pregnancies for my Ancestors When Records Are Scarce

How do you, my fellow genealogists determine your female ancestors marriages and first pregnancies? I have tried several ways to do this depending on how much information I have and what information I am able to find using various resources. As a general rule of thumb I use the age of 45 years as a cut-off point however, that doesn't always work.

Putting my Evidence Together:

Let's take a look at the information I do have for my children's 3rd great paternal grandparents, Anna Catherine Haynsworth and Captain Edwin Ruthven Plowden and their first child, Dr. Haynsworth Dupree Plowden: 
In looking for the marriage date for E. Ruthven Plowden and Catherine Haynsworth I came across information on Ancestry in the form of, The South Carolina Magazine of Ancestral Research, which read, "Married on Thursday the 17th inst., by the Rev. A. E. Chandler, E. Ruthven Plowden to Catherine, daughter of the late Josiah Haynsworth. (Ibid.)".

Next, I decided to work with a Perpetual Calendar Calculator, one I prefer because it allows me to see the whole year if needed, the first link for the year 1851 is here ( and the second link is for the year 1852 when Haynsworth D. Plowden was born, ( You will find that when looking at the 1851 calendar there are only 2 months in which the 17th falls on a Thursday, April and July. You will also notice in February of 1852 there are 29 days indicating that 1852 was a leap year.

My next step was googling the phrase, "how to calculate pregnancies in the 17th and 18th centuries". What I found was a Wikipedia article entitled "Naegele's Rule".  Naegele's Rule is named after a German born obstetrician, Dr. Franz Karl Naegele (1778-1851). He created the rule as a standard way of calculating the due date for pregnancy. A method that is still used today! 

The method is this, "The rule estimates the expected date of delivery (EDD) (also called EDC, for estimated date of confinement) from the first day of the woman's last menstrual period (LMP) by adding one year, subtracting three months, and adding seven days to that date. The result is approximately 280 days (40 weeks) from the start of the last menstrual period." Now of course, in the 21st century there are other more effective ways and with the help of technology in determining ovulation, conception and due dates.

Naelgele's Rule does have at least one flaw though, for instance, his formula is based on every woman having a 28 day cycle, which we now know is not true. However, it was the best way for me to determine a couple of things. Since I know the birthday of the child in question I was able to work backwards to determine (1) what month that Ruthven and Catherine were married in and (2) going backwards from their son's birth I can estimate an approximate date of conception between the end of May 1851 and the middle of June 1851, give or take a few days. Dr. Haynsworth D. Plowden was born on March 20th, 1852.


The South Carolina Magazine of Ancestral Research SCMAR, database, Ancestry, ( : 1 August 2015) entry for E. Ruthven Plowden and Catherine Haynsworth, SCMAR, Vol. XIV, Winter 1986, Marriage and Death Notices form the Sumter Banner, No.1, p. 35; 

Wikipedia Contributors, Naegele's Rule, Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, ('s_rule : 9 August 2015)

Calendar Year for 1851, Year by Year Calendar, The Infoplease Perpetual Calendar, ( : 9 August 2015).

Calendar Year for 1852, Year by Year Calendar, The Infoplease Perpetual Calendar, ( : 9 August 2015)