Unplanned pregnancy tied to kidney transplant rejection 2 years postpartum

Key takeaways:

• Women with unintended pregnancies were more likely to have mycophenolate exposure and allograft loss at 2 years postpartum.
• Unintended pregnancy was not linked to acute kidney rejection or allograft survival.

Unintended pregnancy after kidney transplantation was not linked to perinatal acute allograft rejection but was associated with mycophenolate exposure and allograft loss at 2 years postpartum, according to data published in O&G Open.

In an analysis of than 1,700 pregnancies of kidney transplant recipients from 1967 to 2019, researchers found that nearly 40% of the pregnancies were unintended, highlighting gaps in reproductive health counseling and the need for targeted interventions for a high-risk obstetric population.

“The study emphasizes the necessity of optimizing health before conception. Ensuring adequate time for recovery posttransplantation, managing hypertension, and avoiding teratogenic medications like mycophenolate are critical steps,” Yalda Afshar, MD, PhD, physician-scientist in maternal-fetal medicine at the David Geffen School of Medicine at UCLA, told Healio. “Preconception counseling and routine reproductive health follow-up can help [patients] make informed decisions, reduce unintended pregnancy rates and improve maternal and graft health.”

Afshar and colleagues conducted a retrospective cohort study with 1,723 pregnancies in women who underwent kidney transplantation and were enrolled in the Transplant Pregnancy Registry International. All women had deliveries from 1967 to 2019 and were categorized as intended (62.7%) or unintended (37.3%) pregnancies.

Yalda Afshar

Primary outcome was biopsy-proven acute kidney rejection during pregnancy or by 6 weeks postpartum. Secondary outcomes included allograft loss, defined as the need for dialysis or repeat transplant, severe maternal morbidity and neonatal composite morbidity.

Unintended pregnancy risk factors included:

• younger age (median age, 29.3 years vs. 31.3 years; P < .001);
• self-reported Black race (11.5% vs. 4%; P < .001);
• nulliparity (57.6% vs. 51.1%; P = .01);
• chronic hypertension (48.5% vs. 41.9%; P = .01); and
• transplant from deceased donor (44% vs. 32%; P < .001).

“Unintended pregnancy serves as a marker of social vulnerabilities, such as limited access to contraception and health literacy, which also impact transplant outcomes,” Afshar told Healio. “Addressing these disparities requires a collaborative approach among transplant teams, primary care providers and reproductive health specialists. Comprehensive preconception care empowers transplant recipients to plan pregnancies during optimal health, ensuring the best possible outcomes for mother and baby.”

Both mycophenolate exposure (16% vs. 5.7%) and pregnancy termination (4.7% vs. 0.4%) were more common for women with unintended vs. intended pregnancies (P for both < .001).

Unintended pregnancy was not associated with acute kidney rejection or allograft survival but was independently associated with allograft loss at 2 years postpartum (8.1% vs. 3.5%; adjusted OR = 2.27; 95% CI, 1.32-2.94; P = .003).

Researchers observed no differences for severe maternal morbidity or neonatal composite morbidity for women with intended or unintended pregnancies.

“Our research adds to the body of literature that serves as a call to action for integrating preconception care into standard transplant follow-up protocols, prioritizing the long-term health of reproductive health people before, during and after the pregnancy,” Afshar told Healio.

For more information:

Yalda Afshar, MD, PhD, can be reached at yafshar@mednet.ucla.edu; X (Twitter): @yafshar.