Maternal low birth weight plus obesity increases risks for pregnancy complications
Women are at higher risks for gestational hypertension, preeclampsia and gestational diabetes if they are born underweight and develop obesity or overweight prior to becoming pregnant, according to findings published in Obesity.
“Some individuals who are programmed for increased disease risk develop chronic diseases, despite healthy environmental and lifestyle effects, that may be due to genetic predisposition, whereas others develop disease only when exposed to a ‘second hit,’” Prabha H. Andraweera, PhD, MBBS, a biomedical fellow at University of Adelaide in Australia, and colleagues wrote. “Pregnancy is increasingly being recognized as a common second hit for females. ... Therefore, women who were born small may experience pregnancy complications when exposed to the second hit of pregnancy.”
Andraweera and colleagues analyzed data from 5,327 women with first, singleton pregnancies who were recruited from sites in Australia, New Zealand, the United Kingdom and Ireland as part of the Screening fOr Pregnancy Endpoints (SCOPE) study from November 2004 to February 2011. Participants were interviewed at 15 and 20 weeks of gestation. Birth weight and time of birth were self-reported and confirmed by medical records in 82.7% of participants. At the 15-week interview, participants were measured for weight, height and blood pressure.
Among the cohort, 6.7% had gestational hypertension, 6.5% had preeclampsia, 8.1% had offspring small for gestational age, 4.1% had spontaneous preterm birth, 3.1% had gestational diabetes and 26.7% had other complications. The odds of developing preeclampsia (adjusted OR = 1.7; 95% CI, 1.0-2.9), gestational hypertension (aOR = 2.2; 95% CI, 1.3-3.7), small for gestational age pregnancy (aOR = 1.9; 95% CI, 1.1-3.2) and gestational diabetes (aOR = 2.4; 95% CI, 1.0-5.8) were higher for women with a birth weight of less than 2,500 grams compared with women with a birth weight between 3,000 and 3,499 grams.
The researchers also examined the connection between birth weight and the development of overweight and obesity on pregnancy complications by stratifying the cohort into four groups. Group one, which was used for reference, consisted of women with birth weight at least 2,500 grams and BMI less than 25 kg/m2 at 15 weeks of gestation. Group two consisted of women with birth weight at least 2,500 grams and BMI at least 25 kg/m2 at 15 weeks of gestation. Group three consisted of women with a birth weight below 2,500 grams and BMI less than 25 kg/m2 at 15 weeks of gestation. Finally, group four consisted of women with a birth weight of less than 2,500 grams who had BMI at least 25 kg/m2 at 15 weeks of gestation. Participants in group four had the highest adjusted risks for preeclampsia (aOR = 2.3; 95% CI, 1.2-4.5) and gestational diabetes (aOR = 3.2; 95% CI, 1.1-9.5), while group three had the highest risk for gestational hypertension (aOR = 3.0; 95% CI, 1.6-5.9).
“Those who are born with a low birth weight may be programmed in utero for later-life hypertension. When such individuals experience added stresses, including an elevated BMI or the hemodynamic burden of pregnancy, they may develop [gestational hypertension] or [preeclampsia],” the researchers wrote. “The mechanism of hypertensive diseases of pregnancy in women with low birth weight could be renally mediated via programming of the renin–angiotensin–aldosterone system, suggesting a subclass of hypertensive diseases in pregnancy.” – by Phil Neuffer
Disclosures: The authors report no relevant financial disclosures.