Interpregnancy interval and singleton pregnancy outcomes after frozen embryo transfer

The effect of interpregnancy interval on preterm birth and low birth weight in singleton pregnancies conceived without assistance or by infertility treatments

OBJECTIVE

To determine the association of interpregnancy interval on perinatal outcomes and whether this was influenced by mode of conception.

DESIGN

Retrospective cohort.

SETTING

Centers for Disease Control and Prevention's natality national database.

PATIENT(S)

Patients who had an index singleton live birth with a preceding live birth. Index pregnancies from 2016 to 2019 were conceived with in vitro fertilization (IVF) (n = 32,829) or ovulation induction/intrauterine insemination (OI/IUI) (n = 23,016) or without assistance (n = 7,564,042).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The primary outcomes evaluated were preterm birth (<37 weeks) and low birth weight (<2,500 g). Multivariable logistic regression was performed to evaluate the association of interpregnancy intervals with perinatal outcomes stratified by mode of conception. Adjusted odds ratios and 95% confidence intervals (CIs) were presented.

RESULT(S)

Compared with the interpregnancy interval reference group of 12 to <18 months, a <12 month interpregnancy interval was associated with an increase in preterm birth (<37 weeks) for pregnancies conceived with OI/IUI or without assistance (aOR, 1.42; 95% CI, 1.16-1.74, and aOR, 1.14; 95% CI, 1.13-1.15, respectively), whereas IVF was not associated with an increase (aOR, 0.90; 95% CI, 0.77-1.04). A <12 month interpregnancy interval was associated with an increase in low birth weight for pregnancies conceived with IVF or OI/IUI or without assistance (aOR, 1.34; 95% CI, 1.09-1.64; aOR, 1.33; 95% CI, 1.01-1.76; and aOR, 1.26; 95% CI, 1.24-1.27, respectively).

CONCLUSION(S)

An interpregnancy interval of at least 12 months reduces adverse perinatal outcomes for pregnancies conceived with and without infertility treatment.

The live birth and neonatal outcomes in the subsequent pregnancy among patients with adverse pregnancy outcomes in first frozen embryo transfer cycles

PURPOSE

To explore whether the adverse pregnancy outcomes in first frozen embryo transfer (FET) cycles affect live birth and neonatal outcomes in the subsequent pregnancy?

METHODS

This was a retrospective study. Women with a history of adverse pregnancy outcomes in first FET cycles started their subsequent embryo transfer cycles. The adverse pregnancy outcomes included biochemical pregnancy, ectopic pregnancy, and first-trimester pregnancy loss. The main outcomes of present study were live birth rate and neonatal outcomes.

RESULTS

Results showed patients with first-trimester pregnancy loss in first FET cycles had a 95 percent greater chance of live birth in subsequent FET cycles (OR 1.95, 95% CI 1.33-2.88). However, the biochemical pregnancy/ectopic pregnancy in initial FET cycles did not affect the chance of live birth in second cycles (biochemical pregnancy: OR 1.21, 95% CI 0.82-1.77; ectopic pregnancy: OR 1.06, 95% CI 0.55-2.05). The neonatal outcomes of singletons were not affected by the number of embryo transfer cycles.

CONCLUSIONS

Patients with first-trimester pregnancy loss in first FET cycle had a greater chance of live birth in second FET cycles, but the biochemical pregnancy/ectopic pregnancy in first FET cycles did not significantly affect the live birth in second FET cycles. The three types of adverse pregnancy outcomes in first FET cycles did not affect neonatal outcomes in the second cycles.

Selecting the optimal gestational carrier: medical, reproductive, and ethical considerations

The goals of a gestational surrogacy relationship are to have a healthy baby for the intended parents while maintaining the medical and psychological well-being of the gestational carrier. A successful gestational surrogacy relationship will result also in good psychosocial outcomes for the gestational carrier, intended parents, and child. Finding a gestational carrier who will achieve these goals would be the ideal. This article focuses on key medical, reproductive, and ethical considerations to optimize clinical outcomes in gestational carrier cycles. Recommendations from available clinical guidelines regarding gestational surrogacy are reviewed, along with updates from current literature.