Maternal vascular-placental axis in the third trimester in women with gestational diabetes mellitus, hypertensive disorders, and unaffected pregnancies

Background

Hypertensive disorders of pregnancy and gestational diabetes mellitus are characterized by vascular dysfunction and are associated with long term cardiovascular risks.

Objective

This study aimed to compare different markers of maternal vascular function in women with gestational diabetes mellitus, preeclampsia, or gestational hypertension and in women whose pregnancies were unaffected by these complications and to assess the association between maternal vascular function and markers of placental perfusion and maternal vascular-placental axis in 4 groups of women.

Study Design

This was a prospective observational study of women who had routine hospital visits at 35 0/7 to 36 6/7 weeks of gestation at King’s College Hospital, London, United Kingdom. The routine hospital visit included recording of maternal demographic characteristics and medical history, ultrasound examination for fetal anatomy and growth, Doppler studies of the uterine arteries and ophthalmic arteries, carotid-femoral pulse wave velocity measurements, estimation of the augmentation index and total peripheral resistance, and measurements of serum placental growth factor and soluble fms-like tyrosine kinase 1. Linear regression analysis was performed for the outcomes of uterine artery pulsatility index multiple of the median, placental growth factor multiple of the median, and soluble fms-like tyrosine kinase 1 multiple of the median. The ophthalmic artery peak systolic velocity ratio, pulse wave velocity, augmentation index, and total peripheral vascular resistance were assessed as potential predictors. This analysis was performed on all women and separately in the different groups.

Results

The study population of 6502 women included 614 (9.4%) with gestational diabetes mellitus, 140 (2.1%) who subsequently developed preeclampsia, and 129 (2.0%) who developed gestational hypertension. Women with gestational diabetes mellitus had increased pulse wave velocity compared with those with pregnancies unaffected by gestational diabetes mellitus, preeclampsia, or gestational hypertension. Women with preeclampsia or gestational hypertension had lower placental growth factor multiple of the median and higher uterine artery pulsatility index multiple of the median, soluble fms-like tyrosine kinase 1 multiple of the median, augmentation index, pulse wave velocity, total peripheral resistance, and ophthalmic artery peak systolic velocity ratio than those with unaffected pregnancies. In women with unaffected pregnancies, the ophthalmic artery peak systolic velocity ratio was predictive of the uterine artery pulsatility index multiple of the median, and ophthalmic artery peak systolic velocity ratio, augmentation index, total peripheral resistance, and pulse wave velocity were predictive of the placental growth factor multiple of the median and the soluble fms-like tyrosine kinase 1 multiple of the median. In women with gestational diabetes mellitus, the ophthalmic artery peak systolic velocity ratio was predictive of the uterine artery pulsatility index multiple of the median; the ophthalmic artery peak systolic velocity ratio, total peripheral resistance, and pulse wave velocity were predictive of the placental growth factor multiple of the median; and total peripheral resistance was predictive of the soluble fms-like tyrosine kinase 1 multiple of the median. In women with preeclampsia, the ophthalmic artery peak systolic velocity ratio was predictive of the uterine artery pulsatility index multiple of the median, placental growth factor multiple of the median, and soluble fms-like tyrosine kinase 1 multiple of the median. In women unaffected by gestational diabetes mellitus, preeclampsia, or gestational hypertension, the ophthalmic artery peak systolic velocity ratio was predictive of the uterine artery pulsatility index multiple of the median, and the augmentation index, total peripheral resistance, pulse wave velocity, and the ophthalmic artery peak systolic velocity ratio were predictive of the placental growth factor multiple of the median and the soluble fms-like tyrosine kinase 1 multiple of the median.

Conclusion

In the third trimester of pregnancy, women with preeclampsia, gestational hypertension, and gestational diabetes mellitus present with increased arterial stiffness. In addition, women diagnosed with hypertensive complications showed increased peripheral vascular resistance. The ophthalmic artery peak systolic velocity ratio provided predictive information for placental perfusion and function in all pregnant women, whereas vascular indices were more informative for placental function in women with unaffected pregnancies and those with gestational diabetes mellitus than in those with preeclampsia or gestational hypertension. Our data suggest that vascular assessment in women during pregnancy not only may provide information about maternal vascular health but also can be used to provide information about individual risk factors for placental insufficiency. The selection of the vascular index will have to be tailored according to the maternal profile and pregnancy complication.