O-186 Paternal age is significantly related with the type of delivery and the sex of the newborn in IVF or ICSI cycles with donated oocytes
Authors: Navarro Gomez-Lechon A , Hervás I , Gil Juliá M , Mossetti L , Rivera Egea R , Garrido N 
Published: June 2022

Abstract

Study question
Does paternal age have any effect on obstetric and perinatal outcomes in in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycles with donated oocytes?

Summary answer
Newborn sex and type of delivery, but not other obstetric and perinatal outcomes measured, were significantly different when comparing our paternal age groups.

What is known already
Currently there is a delay in fatherhood that has led to an increase of the average male age at which the first child is conceived. Studies relating paternal age with reproductive risks are increasing and results are controversial leading to a need of more research about it, which this study tries to address. Studies considering treatments with donated oocytes (controlled female factor) allow for a better understanding of male factor and reproductive risks. These risks for the mother and offspring need to be properly assessed and therefore it is important to study whether they can be affected by paternal age.

Study design, size, duration
This retrospective observational multicentric cohort study has considered pregnancies and children conceived from donor IVF-ICSI performed to couples in Spain IVIRMA clinics between January 2008 and March 2020 using patients’ own sperm. Paternal age ranged from 21 to 54 years. The study population was divided in three groups: &lt;30(A, reference), 30-40(B) and &gt;40(C) years. The data available and included consisted of 16382 patients who had a delivery with a live birth and 17988 singleton newborns.

Participants/materials, setting, methods
We evaluated pregnancies and children from donor IVF-ICSI with own semen, known age and resulting in a delivery. Data were obtained from the patient’s clinical charts to build the database to analyze the main outcomes of the study. P &lt; 0.05 was considered statistically significant. We measured several obstetric and perinatal outcomes that were adjusted according to selected patients’, cycles’ and semen samples’ characteristics, as well as donor age, gestational age, type of delivery and newborn sex.

Main results and the role of chance
The analysis included: 233 newborns for A, 6539 for B and 11216 for C. Results are expressed as rate with 95%CI.
There were no statistically significant differences for the incidence of gestational diabetes, anemia, pre-eclampsia or preterm birth; newborn weight, length, cranial circumference, Apgar score (1, 5 and 10 min) and NICU admission between the reference younger group (A) and the older paternal age groups (B and C).
However, there were statistically significant differences for the incidence of hypertension between A 18.1%(10.5-28.1) and B 9.8%(8.8-10.9) with OR = 0.5(0.3-0.9)(p = 0.015); for delivery type between A[cesarean 44.0%(37.2-51.0)] and C[cesarean 64.0%(63.1-65.0)] with OR = 2.3(1.7-3.0)(p &lt; 0.001); and for newborn sex between A[female 55.1%(48.2-61.8)] and B[female 48.2%(46.9-49.4)] with OR = 0.8(0.6-1.0)(p = 0.047).
Therefore, these results suggest an increased risk of cesarean delivery in the older age group compared to the younger one and of having a male birth in the 30-40 group compared to the younger group. There was also a decreased risk of hypertension in 30-40 group compared to &lt; 30 group, which should be clarified in further studies.
After adjusted analysis, there were still significant differences for newborn sex between A and B (p = 0.048) and for delivery type between A and C (p = 0.043), but no significant differences for hypertension were observed.

Limitations, reasons for caution
Due to the retrospective nature of this study there are some biases derived from the clinical practice. Although there is some missing data limiting sample size, this is still large. Moreover, it considers donated oocytes (controlling female factors) limiting the generalization of our results to a population of young women.

Wider implications of the findings
Studies focusing on paternal age are increasing due to fatherhood delay, being results controversial. Paternal age comparison showed significant differences for hypertension, delivery type and newborn sex, however adjusted analysis only found an increased risk of cesarean delivery in C vs. A and of male newborn in B vs. A.

Trial registration number
NA