Pregnancy outcomes in patients with late-onset severe OHSS following different methods of ascetic fluid drainage and a comparison with non-OHSS IVF patients

Abstract

Purpose: In this study, we aimed to identify whether there are any differences in pregnancy outcomes in patients with severe ovarian hyperstimulation syndrome (OHSS) following the drainage of ascites by central venous catheter or paracentesis. We also aimed to identify differences in pregnancy outcomes between severe OHSS patients and non-OHSS IVF patients.

Methods: This was a retrospective cohort analysis carried out in a university-affiliated reproductive center between 2012 and 2019 featuring 359 women with severe OHSS following ascites draining and 345 non-OHSS women (matched by age and the number of oocytes retrieved). We investigated the rates of clinical pregnancy, multiple pregnancies, miscarriage, live birth, and preterm delivery, between the two groups. Within the OHSS group (central venous catheter group vs paracentesis group), we also analyzed the odds ratios and 95% confidence intervals of clinical pregnancy.

Results: The rate of biochemical pregnancy loss in non-OHSS patients was significantly higher than that of severe OHSS patients (11.1% vs. 0.6%; P < 0.05). Live birth rate and the rate of multiple pregnancy (twin pregnancy) were much higher in the severe OHSS group than in the non-OHSS group (88.9% vs. 73.5%; 57.6% vs. 28.1%, respectively). There was no significant difference between the rate of singleton and twin preterm delivery, and neonatal birth weight between the OHSS and the non-OHSS groups. Binary logistic regression analysis revealed that multiple pregnancy and the long superovulation protocol had high odds ratios (odds ratio (OR) = 2.53), thus suggesting that these are significant risk factors for severe OHSS. When considering the patients with severe OHSS and the manner in which they underwent ascites drainage, we found that the volume of ascites in the central venous catheter group was significantly higher than that in the abdominal paracentesis group (P < 0.05). There were no significant difference between the two groups with regards to the number of live births and the birth weight of singletons and twins (P > 0.05), although the premature birth rate of singletons in abdominal paracentesis group was 9.3% (10/107), compared with 3.75% in the central venous catheter group (P < 0.05).

Conclusion: Analysis indicated that for women undergoing in vitro fertilization embryo transfer (IVF-ET), a higher number of antral follicle count, COS long protocol, and multiple pregnancy may be risk factors for late-onset OHSS. Both paracentesis and central venous catheters are effective modalities for the management of ascites in patients with severe OHSS. Catheters represent a safe and effective way to treat patients who need to undergo repeated paracentesis.

Keywords: Ascites draining; Central venous catheter; IVF-ET; OHSS; Paracentesis; Pregnancy outcome.