Hypertension in Pregnant Renal and Liver Transplant Recipients

Usage of Tacrolimus and Mycophenolic Acid During Conception, Pregnancy, and Lactation, and Its Implications for Therapeutic Drug Monitoring: A Systematic Critical Review

BACKGROUND

Conception, pregnancy, and lactation following solid organ transplantation require appropriate management. The most frequently used immunosuppressive drug combination after solid organ transplantation consists of tacrolimus (Tac) plus mycophenolic acid (MPA). Here, the effects of Tac and MPA on fertility, pregnancy, and lactation are systematically reviewed, and their implications for therapeutic drug monitoring (TDM) are discussed.

METHODS

A systematic literature search was performed (August 19, 2019) using Ovid MEDLINE, EMBASE, the Cochrane Central Register of controlled trials, Google Scholar, and Web of Science, and 102 studies were included. Another 60 were included from the reference list of the published articles.

RESULTS

As MPA is teratogenic, women who are trying to conceive are strongly recommended to switch from MPA to azathioprine. MPA treatment in men during conception seems to have no adverse effect on pregnancy outcomes. Nevertheless, in 2015, the drug label was updated with additional risk minimization measures in a pregnancy prevention program. Data on MPA pharmacokinetics during pregnancy and lactation are limited. Tac treatment during conception, pregnancy, and lactation seems to be safe in terms of the health of the mother, (unborn) child, and allograft. However, Tac may increase the risk of hypertension, preeclampsia, preterm birth, and low birth weight. Infants will ingest very small amounts of Tac via breast milk from mothers treated with Tac. However, no adverse outcomes have been reported in children exposed to Tac during lactation. During pregnancy, changes in Tac pharmacokinetics result in increased unbound to whole-blood Tac concentration ratio. To maintain Tac concentrations within the target range, increased Tac dose and intensified TDM may be required. However, it is unclear if dose adjustments during pregnancy are necessary, considering the higher concentration of (active) unbound Tac.

CONCLUSIONS

Tac treatment during conception, pregnancy and lactation seems to be relatively safe. Due to pharmacokinetic changes during pregnancy, a higher Tac dose might be indicated to maintain target concentrations. However, more evidence is needed to make recommendations on both Tac dose adjustments and alternative matrices than whole-blood for TDM of Tac during pregnancy. MPA treatment in men during conception seems to have no adverse effect on pregnancy outcomes, whereas MPA use in women during conception and pregnancy is strongly discouraged.

Pregnancy outcomes in female patients exposed to cyclosporin-based versus tacrolimus-based immunosuppressive regimens after liver/kidney transplantation: A systematic review and meta-analysis

WHAT IS KNOWN AND OBJECTIVE

Pregnancy after transplantation is a challenge owing to the high risk of adverse maternal and foetal outcomes, and immunosuppressants may further impact these outcomes. There are no head-to-head randomized controlled trials comparing influences of cyclosporin and tacrolimus on pregnancy outcomes. Thus, we systematically reviewed and meta-analysed observational studies assessing the comparative influences of these two drugs on pregnancy outcomes in liver/kidney transplant recipients.

METHODS

Relevant studies comparing pregnancy outcomes with tacrolimus and cyclosporin head-to-head were searched in PubMed, EMBASE and Web of Science (from 1 January 2000 to 20 March 2020). The weighted mean difference and odds ratio (OR) were calculated to compare continuous and dichotomous variables, respectively, with 95% confidence intervals (CIs). Publication bias was estimated using funnel plots. The study quality was assessed according to the modified Newcastle-Ottawa scale.

RESULTS AND DISCUSSION

Overall, 10 observational studies of low quality, including a total of 1080 post-liver or kidney transplant pregnancies, were identified. Tacrolimus-treated recipients experienced a lower risk of gestational hypertension (28.0%; OR: 1.74; 95% CI: 1.27-2.39; p < 0.01). Cyclosporin-treated recipients showed a lower incidence of caesarean section (40.3%; OR: 0.62; 95% CI: 0.46-0.82; p < 0.01). Additionally, cyclosporin performed better in terms of the live birth rate (78.0%; OR: 1.38; 95% CI: 1.02-1.88; p = 0.04). No significant differences in the incidences of pre-eclampsia, gestational diabetes, preterm delivery and birth weight were observed.

WHAT IS NEW AND CONCLUSION

Tacrolimus performed better in patients with gestational hypertension, while cyclosporin was associated with a lower incidence of caesarean section and a higher incidence of live birth. The findings are based on relatively low-quality evidence, but may provide a reference for clinicians in their clinical monitoring and obstetric care for post-transplant pregnancies.

Pregnancy Outcomes After Renal Transplantation: A Retrospective Case Series

Objective: To investigate the clinical characteristics and outcomes of pregnancies after renal transplantation (RT).

Materials and Methods: A retrospective study was employed. Data of obstetric, transplantation, pregnancy outcomes, and maternal and neonatal complications from 2000 to 2017 were obtained from a single obstetrics center.

Results: Eleven cases of pregnancies were included: the mean age at conception was 31.27 ± 3.44 (26–36, median 32) years and interval from RT to pregnancy was 51.18 ± 30.65 (25–132, median 38) months. The nine successful pregnancies (9/11) were all in women who maintained their immunosuppressive regimens. All infants were delivered by cesarean section for severe pre-eclampsia in eight cases and placental abruption in one case at a mean gestational age of 34.67 ± 1.41 (30–38) weeks and a median birth weight of 2374.56 ± 569.00 (1,325–3,070) g. Four of nine infants had low birth weight, and six of nine infants underwent premature delivery. The babies had no postpartum complications or congenital anomalies at follow-up period (12–180 months, mean 98.18 ± 54.73 months). One infant was transferred to the neonatal intensive care unit for neonatal asphyxia. Nine cases were uncomplicated at the first trimester, but developed severe pre-eclampsia after the second trimester. Two patients had allograft dysfunction from the second trimester and delivered at the third trimester, and then lost the allografts at 2 and 6 years postdelivery, respectively, whereas the other seven patients had well-functioning allografts at an average follow-up of 108 months. Two patients who decreased their immunosuppressive regimens and developed severe complications had second trimester therapeutic abortion and lost their allografts

Conclusions: During pregnancy, RT patients exhibit risks for the mother, fetus, newborn, and allograft. Decreasing immunosuppressors leads to poor outcomes. With proper peritransplant and periconceptional counseling, these patients can have acceptable pregnancy outcomes.