Almahmeed B, et al. – The purposes of this study were to examine the association between increasing parity and diabetes in a large, population–based cohort as well as to investigate if this relationship is different among high–risk ethnic groups. The findings demonstrated that there was a positive and graded relationship between increasing parity and risk of development of diabetes. However, the influence of parity was observed in all ethnicities. This relationship might be partly related to increased weight gain and retention with increasing parity, or deterioration in β–cell function.

Methods

• It was a population-based, retrospective cohort study.
• This study was performed in seven hundred thirty eight thousand four hundred forty women aged 18–50 years, who delivered babies in Ontario between 1 April 2002 and 31 March 2011.
• After that, diabetes incidence postpartum was calculated for each parity and ethnic group.
• Finally, a multivariable analysis of the effect of parity and ethnicity on the incidence of diabetes was performed utilizing a Cox proportional hazards model, adjusting for confounders.

Results

• According to the findings obtained, the diabetes incidence rate per 1000 person-years was 3.69 in women with 1 delivery, 4.12 in women with 3 deliveries and 7.62 in women with ≥5 deliveries.
• It was observed in the findings that women with ≥3 deliveries had a higher risk of developing diabetes compared with women with 1 delivery [adjusted hazard ratios 1.06 (95% CI 1.01–1.11) for 3 deliveries, 1.33 (95% CI 1.25–1.43) for 4 deliveries and 1.53 (95% CI 1.41–1.66) for ≥5 deliveries).
• A similar rise in risk could be found in Chinese and South-Asian women, with the most influence in Chinese women [hazard ratio 4.59 (95% CI 2.36–8.92) for ≥5 deliveries].