Pregnancy complications among women born preterm

Abstract

Research CMAJBackground: Adults who were born with low birth weights are at increased risk of cardiovascular and metabolic conditions, including pregnancy complications. Low birth weight can result from intrauterine growth restriction, preterm birth or both. We examined the relation between preterm birth and pregnancy complications later in life. Methods:We conducted a population-based cohort study in the province of Quebec involving 7405 women born preterm (554 < 32 weeks, 6851 at 32-36 weeks) and a matched cohort of 16 714 born at term between 1976 and 1995 who had a live birth or stillbirth between 1987 and 2008. The primary outcome measures were pregnancy complications (gestational diabetes, gestational hypertension, and preeclampsia or eclampsia).Results: Overall, 19.9% of women born at less than 32 weeks, 13.2% born at 32-36 weeks and 11.7% born at term had at least 1 pregnancy complication at least once during the study period (p < 0.001). Women born small for gestational age (both term and preterm) had increased odds of having at least 1 pregnancy complication compared with women born at term and at appropriate weight for gestational age. After adjustment for various factors, including birth weight for gestational age, the odds of pregnancy complications associated with preterm birth was elevated by 1.95-fold (95% confidence interval [CI] 1.54-2.47) among women born before 32 weeks' gestation and 1.14-fold (95% CI 1.03-1.25) among those born at 32-36 weeks' gestation relative to women born at term. Interpretation:Being born preterm, in addition to, and independent of, being small for gestational age, was associated with a significantly increased risk of later having pregnancy complications. Abstract

Effect of fetal and child health on kidney development and long-term risk of hypertension and kidney disease

“…As outlined elsewhere in this series, risk of preeclampsia in a mother is increased by her being of LBW (OR 1.69, 95% CI 1.4 -2.02), premature (OR 1.95, 95% CI 1.54-2.47), or by her parents being born in pre-eclamptic pregnancies (OR 2.2, 95% CI 2.0 -2.4) demonstrating the complexity of intergenerational programming [23][24][25] . Pre-pregnancy maternal CKD and hypertension are also significant risk factors for preeclampsia, LBW and preterm delivery 26 .…”

“…Maternal obesity, now occurring in 15 -20% of pregnancies, is a strong risk factor for gestational diabetes, as is maternal prematurity 25,28 . In experimental animals, maternal hyperglycemia is associated with reduced nephron number, higher blood pressures, microalbuminuria and reduced GFRs in offspring 29 .…”

“…Prematurity has predominantly been associated with higher, but still normal, blood pressures as cohorts studied are still relatively young. Overt hypertension has been documented in 2 studies of premature subjects, one of 2 years olds where the prevalence of hypertension (defined as a systolic or diastolic blood pressure > 95 th percentile) was 30% overall, and another of pregnant women aged 25 years, where chronic hypertension was present in 1.4% of those born preterm compared to 0.8% born at term (OR 1.7; 95% CI, 1.32-2.20) 25,56 . Several studies have tried to dissect the relative roles of prematurity and growth restriction.…”

Preterm birth: risk factor for early-onset chronic diseases

“…8 Hypertension has consistently been shown to be more prevalent among adults born preterm, with an inverse correlation between systolic blood pressure and gestational age. 9 Metaanalyses have shown higher resting systolic blood pressure (mean difference [MD] 3.8 mm Hg, 95% CI 2.6 to 5.0 mm Hg) in people born preterm from childhood to young adulthood, along with higher diastolic blood pressure (MD 2.6 mm Hg, 95% CI 1.2 to 4.0 mm Hg) and 24-hour ambulatory systolic blood pressure (MD 3.1 mm Hg, 95% CI 0.3 to 6.0 mm Hg). [10][11][12] The effect of prematurity on blood pressure is of particular relevance for women during their reproductive years.…”

Preterm Birth and Hypertension Risk

“…21 We have also recently shown in a population-based study in Quebec, Canada, that women born preterm, particularly if birth occurred <32 weeks gestation, had an increased risk (independent of birth weight) of pregnancy complications (including gestational diabetes mellitus, gestational hypertension, and preeclampsia), as well as chronic hypertension compared with women born at term. 22 It is to be noted, however, that many studies have not taken into account the effect of other confounding factors, such as chronic lung disease, that have effect on exercise capacity and thus cardiovascular health.…”