In-vitro fertilization, twin pregnancy and HELLP syndrome: A population-based study

HELLP syndrome (haemolysis, elevated liver enzymes, and low platelets) is a rare, severe complication of pregnancy.We compared the rates of HELLP syndrome following in-vitro fertilization (IVF) versus spontaneous conception, stratified by singleton and twin pregnancies.

All women with singleton or twin live birth or stillbirth in British Columbia, Canada, 2008/09-2020/21, were included; data were obtained from the British Columbia Perinatal Database Registry. Rates of HELLP were compared between IVF and non-IVF groups, stratified by plurality.We used logistic regression to adjust for confounders (e.g., maternal age, smoking, body-mass-index), and to assess the effect modification by plurality.

Among 523,867 women, 16,707 (3.2 %) women conceived using IVF. The proportion of twin deliveries was 14.7 % (2,455/16,707) in IVF group, and 1.2 % (5,882/507,160) in spontaneous conception group.In IVF group, the rates of HELLP syndrome in twin vs singleton pregnancies were 2.6% vs 0.6%, respectively; among those who conceived spontaneously, the rates were 2.3% vs 0.3%, respectively.The adjusted odds ratio (AOR) for HELLP syndrome associated with IVF was 1.64 (95 % confidence interval [CI] 1.32 - 2.04) in singleton pregnancies.The association between IVF and HELLP syndrome was absent in twin pregnancies (AOR 0.75; 95% CI 0.55 - 1.02;P < 0.001 for interaction).

The mode of conception is associated with HELLP syndrome in singleton pregnancies but not in twins. However, in twin pregnancies, the risk of HELLP syndrome is substantially higher than that of singleton pregnancies, regardless of mode of conception. Our results inform preconception counselling and prenatal care for women planningIVF.