Blood pressure in 8- and 10-year-old singleton ICSI children compared to spontaneously conceived children

Introduction: Accumulating evidence suggests that the preimplantation environment has an influence on postnatal development and cardiometabolic health later in life. To evaluate if the in-vitro procedure in humans has longterm consequences on the cardiovascular functioning, we compared blood pressure at the age of 8 and 10 years in children born after intra cytoplasmic sperm injection (ICSI) with children born after spontaneous conception (SC).
Material & Methods: Longitudinal questionnaire data and parameters collected at physical examination including longitudinal blood pressure measurements of 8-year-old ICSI children were compared with results of peers born after SC. At the age of 10 years, 108 of the intial recruited150 ICSI children were re-examined and 93 out of the 147 SC children. All children were singletons born after 32 weeks gestation. Blood pressure measurements were taken using a portable manual sphygmometer, at the same time in the protocol i.e. after the child had been seated for a least five minutes. The measurements were performed at the non-dominant arm in the sitting position after the child had been seated for a least five minutes by a qualified investigator.
Results: Blood pressure measurements were available at 8 years in 100 ICSI and 90 SC children and at 10 years in 104 ICSI and 92 SC children. Birth weight, birth weight SDS, birth length and gestational age did not differ between the ICSI population and the SC group. Anthropometric findings such as height and weight in ICSI and SC children were comparable, at the age of 8 as well at the age of 10 years. Systolic and diastolic blood pressure were higher in ICSI children than in SC children at the age of 8 years (98 mmHg versus 94 mmHg; P , 0.001 and 59 mmHg versus 55 mmHg; P ¼ 0.001 respectively). The difference remained after correcting for birth characteristics (weight, gestational age), maternal factors (age, nulliparity, level of education) and current physical characteristics (age, BMI, pubertal score). Ten-year old ICSI children had a comparable systolic but a lower diastolic blood pressure compared to their spontaneous conceived peers (99 mmHg versus 99 mmHg; P ¼ 0.5 and 65 mmHg versus 68 mmHg; p ¼ 0.002 respectively), although the effect of lower diastolic blood pressure in 10-year-old children attenuated after adjusting for confounders.
Conclusion: ICSI conception is associated with a 5 mmHg increase in blood pressure at 8 years, but this finding could not be confirmed at age 10. Blood pressure levels in childhood are known to be predictive of those in later life. Our findings warrant long-term follow-up of ICSI conceived individuals to assess possible effects of periconception events on cardiovascular health in later life. Currently, ICSI children are examined at the age of 14-15 years.