Reproductive outcomes in women and men conceived by assisted reproductive technologies in Norway: prospective registry based study

Abstract

ObjectivesTo determine whether the perinatal outcomes of women or men who were conceived by assisted reproductive technologies are different compared with their peers who were naturally conceived.DesignProspective registry based study.SettingMedical Birth Registry of Norway.ParticipantsPeople born in Norway between 1984 and 2002 with a registered pregnancy by the end of 2021.ExposurePeople who were conceived by assisted reproductive technologies and have had a registered pregnancy.Main outcome measuresComparing pregnancies and births of people who were conceived by assisted reproductive technologies and people who were naturally conceived, we assessed mean birth weight, gestational age, and placental weight by linear regression, additionally, the odds of congenital malformations, a low 5 min Apgar score (<7), transfer to a neonatal intensive care unit, delivery by caesarean section, use of assisted reproductive technologies, hypertensive disorders of pregnancy and pre-eclampsia, preterm birth, and offspring sex, by logistic regression. The occurrence of any registered pregnancy from people aged 14 years until age at the end of follow-up was assessed using Cox proportional regression for both groups.ResultsAmong 1 092 151 people born in Norway from 1984 to 2002, 180 652 were registered at least once as mothers, and 137 530 as fathers. Of these, 399 men and 553 women were conceived by assisted reproductive technologies. People who were conceived by assisted reproductive technologies had little evidence of increased risk of adverse outcomes in their own pregnancies, increased use of assisted reproductive technologies, or any difference in mean birth weight, placental weight, or gestational age. The only exception was for an increased risk of the neonate having a low Apgar score at 5 min (adjusted odds ratio 1.86 (95% confidence interval 1.20 to 2.89)) among women who were conceived by assisted reproductive technologies. Odds were slightly decreased of having a boy among mothers conceived by assisted reproductive technologies (odds ratio 0.79 (95% confidence interval 0.67 to 0.93)). People conceived by assisted reproductive technologies were slightly less likely to have a registered pregnancy within the follow-up period (women, adjusted hazard ratio 0.88 (95% CI 0.81 to 0.96); men, 0.91 (0.83 to 1.01)).ConclusionsPeople conceived by assisted reproductive technologies were not at increased risk of obstetric or perinatal complications when becoming parents. The proportion of people conceived by assisted reproductive technologies with a registered pregnancy was lower than among people who were naturally conceived, but a longer follow-up is required to fully assess their fertility and reproductive history.

Seven days in medicine: 15-21 March 2023

“…Research has found little evidence that people conceived as a result of fertility treatment have a greater risk of pregnancy complications or worse birth outcomes than their naturally conceived peers when becoming parents, a study in BMJ Medicine reported 3. While IVF conception is associated with fewer pregnancies in adulthood, this may well be explained by social rather than clinical factors, the researchers said.…”

Reproductive outcomes in women and men conceived by assisted reproductive technologies

“…Assisted reproduction technologies (ART) include any treatments related to fertility in which eggs or embryos are manipulated to attain a pregnancy, including in-vitro fertilisation and intracytoplasmic sperm injection. 1 The first baby born by in-vitro fertilisation was in 1978, which was the starting point of ART worldwide. More than 10 million children have since been born in the past 40 years.…”

“…To address this gap, Carlsen and colleagues in the linked article by BMJ Medicine report the findings of the first study to examine this association. 1 Carlsen and colleagues analysed data from the Norwegian Medical Birth Registry and included all women and men born in Norway from 1984 (which was the year of the first baby born who was conceived by ART in Norway) to 2002, which accounted for just more than one million people. The authors then followed up this population up to 2021 and identified all registered pregnancies linked to these women and men.…”

“…Assisted reproduction technologies (ART) include any treatments related to fertility in which eggs or embryos are manipulated to attain a pregnancy, including in-vitro fertilisation and intracytoplasmic sperm injection. 1 …”

“…To address this gap, Carlsen and colleagues in the linked article by BMJ Medicine report the findings of the first study to examine this association. 1 …”