Does parity increase insulin resistance during pregnancy?

Area of Science:

• Reproductive Endocrinology
• Metabolic Health
• Obstetrics

Background:

• Parity, defined as the number of previous births, is a significant demographic factor in women's health.
• Insulin resistance and gestational diabetes mellitus (GDM) are critical concerns during pregnancy.
• Understanding the interplay between parity and metabolic changes is essential for maternal health.

Purpose of the Study:

• To investigate the direct and indirect effects of parity on insulin sensitivity.
• To determine the association between parity and the risk of developing gestational diabetes mellitus (GDM).

Main Methods:

• A cohort study involving 1880 Caucasian women undergoing oral glucose tolerance tests (OGTT) during pregnancy.
• Assessment of peripheral insulin sensitivity index (ISI(OGTT)) and a proxy for beta-cell function (CP/FPG).
• Analysis of OGTT in 75 women across two consecutive pregnancies to evaluate inter-pregnancy changes.

Main Results:

• Univariate analysis suggested a link between higher parity and decreased insulin sensitivity and increased beta-cell function proxy.
• These associations were no longer significant after adjusting for age, pregestational BMI, and weight gain.
• Gestational diabetes mellitus (GDM) was significantly associated with age and pregestational weight, not directly with parity after adjustments.

Conclusions:

• Parity is not an independent risk factor for impaired insulin sensitivity or GDM.
• The observed associations are mediated by age and weight gain, especially with longer interpregnancy intervals.
• Pregnancy progression is associated with worsening insulin sensitivity, influenced by interpregnancy weight changes.