Pregnancy outcome and long-term follow-up after in vitro fertilization in women with renal transplantation.

STUDY QUESTION: What is the child morbidity after IVF in women who have received a kidney transplant?

SUMMARY ANSWER: Overall, obstetric outcome and morbidity in children of women who had undergone renal transplantation and IVF treatment were favourable.

WHAT IS KNOWN ALREADY: There are several studies of the obstetric outcome in women with spontaneous conception after solid organ transplantation as well as studies of obstetric outcome after IVF in general. There are only a few case reports of women with kidney or pancreas-kidney transplantation and deliveries after IVF treatment.

STUDY DESIGN, SIZE, DURATION: A population-based retrospective register study was carried out in Sweden including all women with solid organ transplantation and deliveries after IVF; however, only women with kidney transplants were recruited. It also included information on all singleton deliveries after kidney transplantation and spontaneous conception between 1973 and 2012.

PARTICIPANTS/MATERIALS, SETTING AND METHODS: We cross-linked the IVF registers with the Medical Birth Register, the Patient Register and the Cause of Death Register. Study group 1 consisted of women with kidney transplantation and deliveries after IVF treatment. Study group 2 consisted of women with kidney transplantation and singleton deliveries after spontaneous conception. Group 3 (control group to singletons in study group 1) consisted of women without organ transplantation and with singleton deliveries after IVF, matched for maternal age, parity and date of birth. Group 4 (control group to study group 2) consisted of women without organ transplantation and with singleton deliveries after spontaneous conception, matched for maternal age, parity and year of birth.

MAIN RESULTS AND THE ROLE OF CHANCE: Seven singletons and one set of twins were born after organ transplantation and IVF. All women in this group had renal transplants. Among singletons, two (28.6%) were preterm births (PTB), one (14.3%) had very low birthweight (VLBW) (672 g) and one (14.3%) was small for gestational age (SGA). Two infants had minor birth defects. One woman developed pre-eclampsia (14.3%). Mean age at follow-up of the children was 9.7 years (SD 4.2). Two children were diagnosed with hyperactivity disorders. There were 199 singletons born after renal transplantation and spontaneous conception. The rates of pre-eclampsia (23.6%), PTB (48.5%), LBW (43.7%) and SGA (21.2%) were significantly higher in pregnancies of women with renal transplants who had conceived spontaneously than in pregnancies where there was no transplantation and conception was spontaneous. Neonatal morbidity, early neonatal and infant mortality were all significantly higher. No increase in birth defects was seen. Mean age at follow-up of the children was 14.7 years (SD 9.4). Acute bronchitis, systemic lupus erythematosus and hyperactivity disorders were more common in children delivered to women with renal transplantation than in children delivered to women with no transplanted organs. Otherwise, long-term child morbidity was comparable.

LIMITATIONS, REASONS FOR CAUTION: The women who had received renal transplants and who had given birth after IVF were a small group and may represent a selected group of comparatively healthy women.

WIDER IMPLICATIONS OF THE FINDINGS: The results are important to transplant recipients with infertility problems. Neonatal outcomes after maternal renal transplantation and spontaneous conception were in agreement with the literature. Long-term follow-up of this group of children has long been asked for and findings are included in this report.

STUDY FUNDING/COMPETING INTERESTS: No conflict of interest was reported. The study was supported by grants from Swedish Association of Local Authorities and Regions and by grants from the University of Gothenburg/Sahlgrenska University hospital (LUA/ALF 70940).