Small Size in the Womb Could Mean Poor Heart Health Later

First trimester fetal length associated with cardiovascular risks in childhood and after

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) The rate of human development is the fastest during the first trimester of pregnancy. Fetal growth restrictions during this time could affect the baby's future health.

A recent study found that the first trimester of pregnancy could affect cardiovascular health and metabolic function in childhood and adulthood.

The researchers discovered that a smaller-than-average fetal size during the first trimester was associated with a high risk of developing cardiovascular risk factors after birth.

"Attend all pre-natal appointments."

The lead author of this study was Vincent W. V. Jaddoe, PhD, from the Generation R Study Group, the Department of Epidemiology and the Department of Paediatrics at Erasmus University Medical Center in Rotterdam, Netherlands.

The study included 1,184 mother/child pairs from a previous study called the Generation R Study.

All of the children in the current study had first trimester fetal crown to rump length (length of fetus from top of head to bottom of the buttocks) measurements that were recorded when the fetus had been in the womb for 10 weeks to 13 weeks and 6 days.

The researchers took measurements of the fetus throughout each pregnancy, and then at 6, 12, 24, 36 and 48 months of age after birth.

Follow-up was conducted when the children were on average 6 years old. The children's height, weight, body fat distribution, blood pressure and blood concentrations of total cholesterol, insulin (helps the body use and control the amount of sugar), triglycerides (fats in the blood) and C peptide (show how much insulin is being made) concentration were all measured at follow-up.

The findings showed that a smaller first trimester fetal crown to rump length was significantly associated with the following cardiovascular risk factors in childhood:

  • High total body fat percentage
  • High upper body fat to lower body fat ratio
  • High diastolic blood pressure (blood pressure between heart beats)
  • High total cholesterol concentration

Compared to the children with the lowest first trimester fetal crown to rump lengths, the children with the highest lengths had a 50 percent decreased risk of having three or more of these cardiovascular risk factors in childhood.

Maternal characteristics, childhood body mass index (height to weight ratio), systolic blood pressure (blood pressure when the heart beats) and concentrations of triglycerides, insulin or C peptide were not found to be associated with or affected by a small first trimester fetal crown to rump length.

The researchers suggested that a small first trimester fetal crown to rump length can lead to accelerated growth during childhood to compensate for slow growth in the womb; this accelerated growth could possibly lead to development of cardiovascular risk factors later in life.

The authors mentioned a few limitations of their study.

First, the study limited participants to children with recorded first trimester fetal crown to rump length from a specific age range of three weeks. Second, not all of the mothers participated at follow-up.

Third, the findings may not be applicable to the general population because of the small and specific study population. Fourth, the large amount of tests could have led to false positive associations.

This study was published on January 23 in BMJ.

The Netherlands Organizations of Scientific Research and the Netherlands Organization of Health Research and Development provided funding.

Review Date: 
January 23, 2014
Last Updated:
January 24, 2014