Does Conception Mode Affect Pre-Eclampsia Screening?

Currently, clinicians use first-trimester pre-eclampsia screening to identify high-risk pregnancies early. Specifically, the Fetal Medicine Foundation (FMF) algorithm serves as a global standard. However, we must evaluate how assisted reproductive technology (ART) affects screening accuracy. Therefore, Danish researchers conducted a prospective multicenter study to compare different conception modes.

Analyzing Conception Modes and Biomarkers

In this study, researchers tracked 8,157 pregnant women undergoing routine screening. Specifically, the cohort included 535 women who conceived via ART and 235 after ovulation induction (OI). Additionally, the remaining 7,387 women had spontaneous conceptions. Consequently, clinicians analyzed multiple biophysical and biochemical markers to calculate risk. Furthermore, they measured mean arterial pressure, uterine artery pulsatility index, and serum placental growth factor.

How Pre-Eclampsia Screening Performs in ART

Notably, the incidence of pre-eclampsia varied significantly across the three groups. First, the ART group showed the highest rate at 7.3%. In contrast, the OI and spontaneous conception groups showed rates of 5.1% and 3.4%. Moreover, the incidence peaked at 12.3% among women who received oocyte donation. Consequently, the screen-positive rate reached 28.2% in the ART group. However, the screen-positive rate in the spontaneous group was only 8.6%.

Detection Rates and Biomarker Alterations

Despite these differences, the algorithm maintained robust detection rates for preterm pre-eclampsia. Specifically, the detection rate reached 81.8% in the ART group. Meanwhile, the detection rate was 61.4% in the spontaneous conception group. Indeed, ART patients often exhibit altered biomarker levels. For instance, they show higher mean arterial pressure and lower placental growth factor. Therefore, the algorithm flags more ART pregnancies as high risk.

Clinical Implications for Obstetric Practice

Clearly, these findings have important implications for clinical practice. Since ART pregnancies carry a higher baseline risk, the increased screen-positive rate is clinically appropriate. Consequently, obstetricians should prepare to initiate early low-dose aspirin therapy for these patients. However, doctors must counsel patients about the higher likelihood of a screen-positive result. In conclusion, the FMF algorithm remains a valuable tool for managing fertility-assisted pregnancies.

Frequently Asked Questions

Q1: Why is the screen-positive rate of pre-eclampsia screening higher in ART pregnancies?

This occurs because women who conceive via assisted reproductive technology often show altered baseline biomarkers. Specifically, they tend to have higher mean arterial pressure, higher uterine artery pulsatility index, and lower placental growth factor levels. Consequently, the algorithm more frequently identifies these patients as high risk.

Q2: Does the FMF algorithm perform reliably for pregnancies conceived through ovulation induction?

Indeed, the algorithm maintains strong predictive performance in this group. For example, the study showed a 100% detection rate for preterm pre-eclampsia among patients who underwent ovulation induction. Therefore, clinicians can confidently use this tool for these patients.

Q3: Should obstetricians adjust their clinical management for screen-positive ART patients?

Indeed, obstetricians should closely monitor these high-risk patients. Furthermore, current guidelines recommend initiating low-dose aspirin therapy before 16 weeks of gestation to reduce the risk of developing preterm pre-eclampsia.

References

1. Kjaer ASL et al. Predictive performance of Fetal Medicine Foundation first-trimester screening algorithm for pre-eclampsia according to conception mode. Ultrasound Obstet Gynecol. 2026 May 24. doi: 10.1002/uog.70244. PMID: 42177627.
2. Rolnik DL et al. Aspirin versus placebo in pregnancies at high risk for preterm preeclampsia. N Engl J Med. 2017 Aug 17;377(7):613-622. doi: 10.1056/NEJMoa1704559.
3. Poon LC et al. The International Federation of Gynecology and Obstetrics (FIGO) initiative on pre-eclampsia: A pragmatic guide for first-trimester screening and prevention. Int J Gynaecol Obstet. 2019 May;145 Suppl 1(Suppl 1):1-33. doi: 10.1002/ijgo.12802.