Low Antenatal Care Number of Consultations Is Associated with Gestational Weight Gain and Birth Weight of Offspring of Teenage Mothers: A Study Based on Colombian and Mexican Cohorts.

Background: More than 70% of pregnant adolescents in developing countries experience inappropriate gestational weight gain (GWG).

Objective: To determine the association of the number of antenatal care visits (ANC) with GWG, birth weight, and their differences between two countries.

Methods: A prospective study was conducted in two cohorts of adolescents, one from Mexico and one from Colombia. The study calculated pregestational body mass index (BMI), obtained GWG and birth weight, and collected socioeconomic characteristics. Birth weight was categorized according to gestational age. A total of 690 mother-child pairs were included, of which 42.6% were Colombian and 57.4% Mexican.

Results: The study found no association between socioeconomic characteristics and GWG or birth weight. Colombian adolescents were more likely to experience insufficient GWG (68%), compared with 36% of Mexican adolescents. Colombian adolescents who attended fewer than eight ANC visits were at increased risk of insufficient GWG, whereas Mexican adolescents were at increased risk of excessive GWG. Mexican adolescents who began their pregnancies overweight or obese were at increased risk of excessive GWG. Fewer than eight ANC visits were associated with small for gestational age (SGA) in the Mexican cohort.

Conclusions: Inadequate numbers of ANC visits were associated with excessive and insufficient GWG, and SGA. Promoting ANC in adolescent pregnancy is essential to prevent suboptimal GWG and SGA. This study highlights the need for interventions targeting pregnant adolescents from low socioeconomic backgrounds, prioritizing early initiation of prenatal care (first trimester) and a drastic reduction in the high rates of cesarean sections in this group.