# Optimal timing for diagnosis of gestational diabetes as a determinant of pregnancy outcomes: exploring the particularities in a low-income population

## TL;DR

The study finds that early diagnosis of gestational diabetes in a low-income Brazilian population is linked to fewer maternal complications, possibly due to better prenatal care.

## Contribution

This study identifies that early gestational diabetes diagnosis reduces adverse maternal outcomes in low-income settings through increased prenatal care.

## Key findings

- Early GDM diagnosis was associated with fewer maternal complications like gestational hypertension and pre-eclampsia.
- Late GDM diagnosis was linked to higher odds of composite maternal adverse outcomes.
- No significant differences were found in neonatal outcomes between early and late diagnosis groups.

## Abstract

To identify maternal and neonatal outcomes in pregnancies with early versus
late gestational diabetes mellitus (GDM) diagnosis, considering healthcare
access in a low- to middle-income area of Brazil.

This retrospective study included women diagnosed with either early GDM
(diagnosed before 20 weeks, based on fasting plasma glucose) or late GDM
(diagnosed by 24-28 weeks, via oral glucose tolerance test), according to
the IADPSG criteria, who received prenatal care at a hospital in southern
Brazil. Maternal outcomes included gestational hypertension, pre-eclampsia,
cesarean section or instrumented vaginal delivery, and need for intensive
care after birth. Perinatal outcomes were assessed based on the adequacy of
birth timing and weight for gestational age, the need for neonatal intensive
care, shoulder dystocia or fractures, neonatal hypoglycemia and mortality.
Logistic regression was used to adjust for possible confounders, with
results presented as odds ratios (OR) and 95% confidence intervals (CI).

A total of 320 women with GDM (mean age 32.9 ± 6.5 years) were
included: 164 (51.2%) with early GDM and 156 (48.8%) with late GDM. The
primary composite maternal outcome was more frequent in late GDM (43.6%
versus 29.3%; OR 1.87; 95% CI 1.15-3.03), as well as perineal laceration (OR
2.45; 95% CI 1.22-4.84). No significant differences were found between
groups in the primary composite neonatal outcome, prematurity, or macrosomia
rates.

In this low-income population in southern Brazil, early GDM diagnosis led to
more prenatal consultations and pharmacological treatment, which may have
contributed to reduced adverse maternal outcomes.