Low birth weight and later development of insulin resistance and biochemical/clinical features of polycystic ovary syndrome

Reduced insulin sensitivity in adult life has been reported in subjects born at term small for gestational age (SGA) and in those born prematurely with very low birth weight (LBW) (<1,500 g). We assessed whether LBW (<2,500 g) young women, irrespective of whether they were born SGA or adequate for gestational age (premature AGA), exhibited a reduction in insulin sensitivity through a prospective historical design. The risk of developing biochemical and clinical features of polycystic ovary syndrome was also investigated. The study population included 35 LBW women (19 SGA BW range, 1,000-2,400 g] and 16 premature AGA BW range, 1,700-2,440 g]) aged 21.8 +/- 1.8 years and 35 term AGA controls, of similar age, recruited from a neonatal registry. All women underwent clinical, ultrasonographic, hormonal, and metabolic evaluations, including the composite insulin sensitivity index. Women under hormonal contraception (21.4%) were excluded from hormonal and metabolic analyses. Composite insulin sensitivity index was significantly lower in LBW women even when the 2 LBW subgroups, SGA and premature AGA, were analyzed separately (4.4 +/- 2.2 and 4.0 +/- 1.7, respectively) than in controls (6.9 +/- 4.4). The LBW women showed a significantly higher incidence proportion of irregular menses (14/35 40%] vs 2/35 5.7%]) and a significantly higher free androgen index (5.8 +/- 3.5 vs 3.9 +/- 3.2). They also showed a nonsignificantly higher proportion of hirsutism, acne, and polycystic ovaries. In conclusion, LBW (<2,500 g) young women, irrespective of whether they were SGA and premature AGA, exhibited a reduction in insulin sensitivity as compared with born at term AGA women. Furthermore, they exhibited an increased risk of developing clinical and biochemical features of polycystic ovary syndrome.