Do parental heights influence pregnancy length?: a population-based prospective study, HUNT 2

Abstract

BackgroundThe objective of this study was to examine the association of maternal and paternal height with pregnancy length, and with the risk of pre- and post-term birth. In addition we aimed to study whether cardiovascular risk factors could explain possible associations.MethodsParents who participated in the Nord-Trøndelag Health Study (HUNT 2; 1995–1997) were linked to offspring data from the Medical Birth Registry of Norway (1997–2005).The main analyses included 3497 women who had delivered 5010 children, and 2005 men who had fathered 2798 pregnancies. All births took place after parental participation in HUNT 2. Linear regression was used to estimate crude and adjusted differences in pregnancy length according to parental heights. Logistic regression was used to estimate crude and adjusted associations of parental heights with the risk of pre- and post-term births.ResultsWe found a gradual increase in pregnancy length by increasing maternal height, and the association was essentially unchanged after adjustment for maternal cardiovascular risk factors, parental age, offspring sex, parity, and socioeconomic measures. When estimated date of delivery was based on ultrasound, the difference between mothers in the lower height quintile (<163 cm cm) and mothers in the upper height quintile (≥ 173 cm) was 4.3 days, and when estimated date of delivery was based on last menstrual period (LMP), the difference was 2.8 days. Shorter women (< 163 cm) had lower risk of post-term births, and when estimated date of delivery was based on ultrasound they also had higher risk of pre-term births. Paternal height was not associated with pregnancy length, or with the risks of pre- and post-term births.ConclusionsWomen with shorter stature had shorter pregnancy length and lower risk of post-term births than taller women, and when EDD was based on ultrasound, they also had higher risk of preterm births. The effect of maternal height was generally stronger when pregnancy length was based on second trimester ultrasound compared to last menstrual period. The association of maternal height with pregnancy length could not be explained by cardiovascular risk factors. Paternal height was neither associated with pregnancy length nor with the risk of pre- and post-term birth.

Variants at the ADAMTS13, BGALT5, SSBP2 and TKT Loci are associated with Post-term birth

“…We have identified genetic variants in proximity to the B3GALT5, ADAMTS13, SSBP2, and TKT loci as being associated with post-term birth in two birth cohorts (NFBC1966 and NFBC1986). This finding is consistent with previous observations that suggested there was a genetic component to post-term birth[12, 13, 15–20, 43]. Spatial and mRNA expression analyses further showed provided novel clues about how these loci contribute to the regulation and consequences of post-term birth.…”

“…All genetic analyses also accounted for child’s sex, as this was the only trait that has consistently shown a large effect on post-term birth status in any previous post-term studies[15, 43, 47, 48].…”

Recurrence rate and outcome of postterm pregnancy, a national cohort study

“…29 Factors known to influence length of pregnancy are paternal 30 genetics, maternal height, obesity and male fetal gender [11][12][13][14][15]. 31 Previous studies showed a high recurrence risk of postterm approximately 96% of all deliveries in the Netherlands [21,22].…”

Haplotype genetic score analysis in 10,734 mother/infant pairs reveals complex maternal and fetal genetic effects underlying the associations between maternal phenotypes, birth outcomes and adult phenotypes

“…Epidemiological studies have demonstrated that maternal physical and physiological traits associate with birth outcomes. For example, maternal height is positively associated with gestational duration (1,2), birth weight and birth length (3,4); higher maternal blood glucose is associated with higher birth weight (5); and elevated maternal blood pressure is associated with reduced birth weight (6,7). These birth outcomes in turn associate with many long-term adverse health outcomes in the offspring, such as obesity (8), type 2 diabetes(9), hypertension (10), and cardiovascular diseases (11,12).…”