What biopsychosocial factors are associated with abortions in primary care in Britain? A case control study comparing women aged 13 to 54 who had abortions compared with those who did not.

Date of Approval
Application Number
Technical Summary

Unintended pregnancies make up an estimated 44% of all pregnancies worldwide and 60% of these ends in abortions. Britain has among the highest teenage abortion rates in Europe. Together, these suggest significant room for improvement in contraceptive programmes in Britain and worldwide.

Unplanned pregnancies and abortion may be more complex than a matter of access to and use of effective contraception. Identifying these risk factors could be useful for the design of effective prevention programmes. There is very little research on the use of general practice records to identify those who might be at risk of unplanned pregnancies; studies have identified recent use of emergency contraception and previous pregnancies as risk factors for teenage pregnancies.

We will conduct an observational study using a database of general practice electronic health records (CPRD GOLD). Using a case control method, we will compare women aged 13 to 54 who had an abortion with women who did not, to better understand what the risk factors might be.

For each case, we will randomly select five women of the same age and from the same practice as controls. We will examine risk factors as reported in the literature including use of contraception, parity and previous abortions (linked using CPRD Pregnancy Register), index of multiple deprivation (IMD link), risk taking behaviour (alcohol, smoking and drug use), psychosocial factors (depression, anxiety, domestic violence).

We will use unadjusted and multiple conditional logistic regression for analysis and present odds ratios with 95% confidence intervals to compare postulated risk factors between cases and controls. We will also use interaction terms to examine associations between risk factors, starting with a priori from knowledge or theory.

The findings might help to design better prevention programmes that aim to address the biopsychosocial determinants of unplanned pregnancies and abortions in primary care.

Health Outcomes to be Measured

Abortion is the outcome and “case” definition. We will be examining associations between abortions and biopsychosocial factors (such as history of depression, domestic violence, parity, previous abortions, smoking, alcohol, past consultations for contraception) in women if different age groups.


Richard Ma - Chief Investigator - Imperial College London
Richard Ma - Corresponding Applicant - Imperial College London
Alex Bottle - Collaborator - Imperial College London
Helen Ward - Collaborator - Imperial College London
Sonia Saxena - Collaborator - Imperial College London


Patient Level Index of Multiple Deprivation;Practice Level Index of Multiple Deprivation;Pregnancy Register