Support #1027

Pregnancy status

Added by Lydia Palumbo over 5 years ago. Updated over 5 years ago.

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% Done:



Dear User Support,

I am trying to identify women who were pregnant at the time of the interview. I could find a useful indicator for
UKHLS, which is w_preg, while I was not able to find one for BHPS.
I guess that the only way is to add up children for each wave and see if there are changes in their number. However,
if there are interval censored data, it is not possible to confirm if the woman was pregnant at the time of the
previous interview.

Am I correct or am I missing something?

Thank you and best regards,


Updated by Alita Nandi over 5 years ago

  • Status changed from New to In Progress
  • Assignee set to Alita Nandi
  • % Done changed from 0 to 10
  • Private changed from Yes to No

Hello Lydia,

Many thanks for your enquiry. The Understanding Society team is looking into it and we will get back to you as soon as we can.

Best wishes,


Updated by Stephanie Auty over 5 years ago

  • Status changed from In Progress to Feedback
  • Assignee changed from Alita Nandi to Lydia Palumbo
  • % Done changed from 10 to 70

Dear Lydia,

There is a variable available in Waves 14 and 16 of BHPS, bw_hlpreg, which you could use, but there are also some other methods which you could use to identify people who were pregnant:

1) Child age in months, bw_bwtagm1-3 in bw_indresp, is available from Wave 10 onwards, so this could be used along with the previous interview date.

2) Using the bw_egoalt file, if the variable bw_lwstat has a value of 3 "alter birth", it means that the alter entered the survey through birth, so the mother may have been pregnant in the last interview. The relationship (bw_rel=4 or bb_relationship_bh=9) can also be used to check if the ego for that record is the mother.

3) Using bw_indall, identify children of the respondents using mother identifiers (bw_mnpid_bh for mother's pid) attached to children and then check the age of the children.

4) The birth year (and month in Special Licence) of the respondent's first child is available in ch1by (and ch1bm) in xwavedat – coupled with interview dates.

Best wishes,


Updated by Stephanie Auty over 5 years ago

  • Status changed from Feedback to Resolved
  • % Done changed from 70 to 100

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