No clarity on the definition of parity: A survey accessing interpretation of the word parity amongst obstetricians and midwives and a literature review

OBJECTIVES: We assessed clinical interpretation of the word parity amongst obstetricians and midwives in Wales and performed a literature review to identify a standardised definition.

STUDY DESIGN: A survey was conducted by electronic questionnaire to obstetricians across Wales and midwives across North Wales. The questionnaire was distributed to obstetricians using the Wales Information System. Midwives were surveyed using a health board wide distribution list. This was followed by a literature review using dictionaries, standard texts, professional bodies and websites. References were obtained for the UK, USA, India, Malaysia and West Indies.

RESULTS: There were 143 responses from 63 doctors and 80 midwives. 5% of doctors and 49 % of midwives did not include stillbirths after 24 completed weeks in their definition of parity. 84 % of all surveyed described having a previous twin delivery as Para 2. 23 references were obtained for a definition of parity. Parity was variability defined as the number of conceptions, pregnancies, births and babies. Only 12 sources offered a definition in reference to multiple pregnancy. Of these, 8 sources defined multiple births as a single parous event.

CONCLUSIONS: There are variations in definitions for the term parity from referenced sources and variation in understanding amongst staff surveyed. We recommend UK professional bodies take into consideration the findings of this study and provide a standard consensus definition of parity.