Association of combined second trimester maternal serum Homocysteine and Uterine Artery Doppler to predict adverse pregnancy outcome.

Introduction: Disturbances in placentation increase the risk of maternal and fetal complications. Several biochemical and imaging modalities have been studied, but the hunt for a single effective screening test never became a reality as the causes of this complex condition are multifactorial and polygenetic, many of which we are only beginning to discover. Not many studies have been conducted in the developing countries like India and other low resource settings to consider whether it would be worthwhile to combine inexpensive and effective markers together for better prediction of adverse pregnancy outcome.This study primarily aims to investigate the predictability of combined screening with maternal serum homocysteine and second trimester uterine artery Doppler in diagnosis of adverse pregnancy outcome. Methodology: A prospective cohort study which involved 100 women with singleton gestation, meeting the inclusion criteria, attending the inpatient or outpatient of Obstetrics and Gynaecology in Amrita Institute of Medical Sciences, Kerala, a tertiary care centre in Southern India from July 2016 and September 2018 was conducted. Serum Homocysteine estimation (tHcy) was done between 18 and 28 weeks of gestation with informed consent, and uterine artery (UA) Doppler PI which is a non-invasive routine study was done along with targeted second trimester anomaly scan (18-24 weeks) in Fetal Medicine Department. Cutoff values of tHcy and UA PI were computed at 95th (> / = 9.7 mmol/l) and 90th percentile, respectively as reported by Onalan et al. [9] and Nicholaides et al. [4]. Statistical analysis was performed using IBM SPSS version 20.0 software. Chi-square test and diagnostic measures were also used.
Results: Of the 100 patients, 15% (n = 15) developed hypertensive disorder. 7% (n = 7) had FGR and 7%(n = 7) had spontaneous preterm birth. 6% (n = 6) neonates had an APGAR score < 7 and 8% neonates (n = 8) required immediate NICU admission. Statistically significant association was found when tHcy and UA PI were used together for the prediction of FGR (p = 0.003), preterm birth (p = 0.002) and low APGAR score at birth (p = 0.009) with a specificity of 83.4%. With regard to PIH, both parameters were found to be statistically significant only when used independently (p = 0.001) but not when used in combination (p = 0.17). Both elevated tHcy and abnormal UA PI used in combination predicted adverse pregnancy outcome like FGR but with a low sensitivity of 14.3% and high specificity of 98.9%. However, when used independently these markers predicted FGR with a better sensitivity (tHcy- 28.6% and UA PI- 44.4%).
Conclusion: Findings from this study have been promising with potential clinical implications for the diagnosis and management of high-risk pregnancies. Though the independent role of the two markers in screening various adverse pregnancy outcomes could be proved, their combined use to improve predictivity of more complications warrants further studies on a larger population with appropriate randomisation. © Crown 2021.