Second Study Using Danish Population Data Led By WECARE Director Published in the European Journal of Public Health

A second paper was published this week using Danish data. The paper is titled “Reproductive History Patterns and Long-Term Mortality Rates: A Danish, Population-Based Record Linkage Study”  and co-authors include Drs. David Reardon and Byron Calhoun.  

The general purpose of this extensive study was to explore the effects of particular patterns of pregnancy resolution (induced abortion, miscarriage, and birth) on mortality rates over an extended time frame (25 years).  Specifically examined were: 1) detrimental and/or protective effects of distinct forms of pregnancy resolution over time; 2) detrimental and/or protective effects of distinct forms of pregnancy resolution occurring repeatedly over time; and 3) elevated or attenuated mortality risks when distinct pregnancy outcomes were combined with other forms of pregnancy resolution.
As noted in the article “The primary strengths of the study are the use of large scale population level data that includes reliable records on all possible reproductive outcomes and prospectively gathered data from different birth cohorts of women. The results of comprehensive studies of this nature offer more accurate information regarding mortality risks associated with reproductive outcomes than the data acquired by governmental agencies relying on information primarily garnered from death certificates.”

The results indicated the following:

1)      With controls for the number of pregnancies, year of birth, and age at last pregnancy, having experienced only induced abortion(s) and natural loss(es) was associated with over 3 times the risk of death from all causes compared to only having experienced birth(s). 

2)      Risk of death was over 6 times greater among women who had never been pregnant compared to those in the birth(s) only group.

3)      Compared to a reproductive history that only included births, after instituting controls, increased risk of death were as follows: only induced abortion(s): 66%; only natural loss(es): 181%; all reproductive outcomes 94%.

4)      Compared to no experience of abortion, increased mortality risks after applying controls were evidenced for the following: one abortion: 45% increased risk; two abortions: 114% increased risk; and three abortions: 191% increased risk of death.

5)      Significantly decreased mortality risks were evidenced with multiple births: 2 births were associated with an 83% lower risk of death compared to no births and 3 or more births corresponded to a 44% decreased risk over no births. 

6)      Increased risks of death were equal to 44%, 86%, and 150% for 1, 2, and 3 natural losses respectively compared to no natural losses.

Key points (from the end of the article):

1)      This study offers more accurate information regarding mortality risks associated with reproductive outcomes than the data acquired by death certificates.

2)      Distinct patterns of reproductive outcomes involving induced abortion, spontaneous abortion and birth across a 25 year window are associated with different levels of risk of dying.

3)      Mortality risks associated with induced abortion and spontaneous abortion are more pronounced when more than one is experienced.