[The effects of arterial hypertension during pregnancy on birth weight, intrauterine growth retardation and neonatal evolution. A matched case-control study].

OBJECTIVE

To determine the impact of hypertensive disorders in pregnancy on birth weight, small-for-gestational age births (SGA) and neonatal outcome.

DESIGN

Matched case-control study.

SETTING

A Tertiary Neonatal Intensive Care Unit.

POPULATION AND METHODS

The effects of maternal hypertension were analyzed in 11,358 infants born between January 1990 and December 1996 at the Italian Hospital of Buenos Aires. Infants born to mothers with pregnancy-induced hypertension, preeclampsia or eclampsia were included. Each infant was matched for gestational age to 1 control infant born to normotensive mothers. Exclusion criteria were: twins, intrauterine infections, chronic hypertension and major malformations.

MAIN OUTCOME MEASURES

Birth weight, incidence of SGA infants, neonatal outcome.

RESULTS

279 infants of hypertensive mothers and 279 controls met the inclusion/exclusion criteria and were enrolled. Maternal hypertension was significantly associated with a higher rate of C-section (OR = 3.80; 95% CI: 2.64-5.50); SGA infants (OR = 7.08; 95% CI: 3.07-18.6), low birth weight (LBW) (OR = 1.8, 95% CI: 1.24-2.60) and very low birth weight infants (VLBW) (OR = 2.14; 95% CI: 1.13-4.19). The frequency of low Apgar score at 5 minutes (OR = 3.63; 95% CI: 1.12-15.3), necrotizing enterocolitis (OR = 3.33; 95% CI: 1.23-10.30) and polycythemia (OR = 3.63; 95% CI: 1.12-15.3) was significantly increased in infants born to hypertensive mothers. There were no significant differences regarding other causes of neonatal morbidity and mortality rate.

CONCLUSIONS

Hypertension in pregnancy mainly increased the risk of SGA infants. Furthermore, infants of hypertensive mothers had a higher incidence of LBW, VLBW, low Apgar score at 5 minutes, necrotizing enterocolitis and polycythemia.