No abstract

In a 2-year (1990-92) prospective national investigation, comprising all stillborn and live-born ELBW infants with a birthweight of < or = 1000 g born at 23 completed weeks of gestation or more, we examined the incidence, neonatal mortality, major morbidity and infant survival in relation to level of care and place of residence. A total of 633 ELBW infants were live-born, i.e. 0.26% of all live-born infants, and 298 were stillborn. The average neonatal mortality was 37% and 91% at 23 weeks, 70% at 24 weeks, and 40% at 25 weeks of gestation. Of neonatal survivors, 8% had intraventricular haemorrhage grade 3, 10% retinopathy of prematurity of stage > or = 3, 2% necrotizing enterocolitis, and 28% were oxygen-dependent at a time corresponding to 36 weeks of gestation. In all, 77% were treated with mechanical ventilation, whereas 19% survived without, almost all of them being CPAP treated. Infant mortality among infants born at level III (tertiary centres) was 30%, at level IIa (with full perinatal service) 46% and at level IIb (with basic neonatal service) 55%. Only 1% was born at hospital level I. Regarding the relation to place of residence, the mortality rates among infants residing in the areas served by levels III, IIa and IIb hospitals were 36%, 45% and 41%, respectively. The referral system thus functioned well, but can be improved, and increased perinatal referral, at borderline perinatal viability, might provide a better quality of care and a better chance of survival.

An increased risk for congenital malformations occurs after IVF, similar for the different IVF techniques used, and mainly a consequence of parental characteristics. A few specific conditions show an extra increase in risk.

WHAT'S KNOWN ON THIS SUBJECT:No clear-cut increase in cancer risk after IVF has been found, but most studies were too small to answer the question. There are characteristics of children who are conceived by IVF that could increase cancer risk. WHAT THIS STUDY ADDS:This study is large enough to demonstrate that a slight but statistically significant cancer risk exists for children who are conceived by IVF. An interesting finding is the seeming increase in the risk for histiocytosis. abstract OBJECTIVES: Studies conducted so far have found no statistically significant increased risk for cancer among children who are born after in vitro fertilization (IVF). METHODS:We followed 26 692 children who were born after IVF during the years 1982-2005 by using the Swedish Cancer Register and compared the number of children who had cancer and were born after IVF with children who were not conceived by IVF. Adjustment was made for year of birth. RESULTS:Maternal age, parity, smoking, subfertility, previous miscarriages, BMI, and multiple births did not significantly affect cancer risk in offspring. High birth weight, premature delivery, and the presence of respiratory diagnoses and low Apgar score were risk factors for cancer. We identified 53 cases of cancer in children who were born after IVF against 38 expected cases: 18 of them with hematologic cancer (15 of them acute lymphoblastic leukemia), 17 with eye or central nervous system tumors, and 12 with other solid cancers. There were 6 cases of Langerhans histiocytosis against 1.0 expected. The total cancer risk estimate was 1.42 (95% confidence interval: 1.09 -1.87). CONCLUSIONS:We found a moderately increased risk for cancer in children who were conceived by IVF. Putative intermediary factors could be preterm birth and neonatal asphyxia.

Objective  To investigate obstetric characteristics, maternal morbidity and mortality among Swedish women giving birth after in vitro fertilisation (IVF) treatment. Design  Register study. Setting  Nationwide study in Sweden. Sample  All women known to have had IVF in Sweden 1982–2001. Methods  Using Swedish health registers, women who had given birth after IVF were identified from all Swedish IVF clinics and compared with all women who gave birth. Analysis was performed with the Mantel–Haenszel technique. Main outcome measures  Diagnoses during pregnancy, at delivery and at re‐admission within 60 days after delivery and risk of cancer. Results  IVF women had an increased risk of bleeding in early pregnancy [odds ratio (OR) = 4.59, 95% confidence interval (95% CI) 4.08–5.15] and of ovarian torsion during pregnancy (OR = 10.6, 5.69–10.7). They were also more likely to encounter pre‐eclampsia (OR = 1.63, 1.53–1.74), placental abruption (2.17, 1.74–2.72), placenta praevia (3.65, 3.15–4.23), bleeding in association with vaginal delivery (1.40, 1.38–1.50) and premature rupture of membranes (PROM) (2.54, 2.34–2.76). Interventions including caesarean sections (1.38, 1.32–1.43) and induction of labour (1.37, 1.29–1.46) in singleton pregnancies was more frequent. The type of IVF method had little effect on these results, but there was a tendency for women who had received intra‐cytoplasmatic sperm injection (ICSI) to have slightly fewer complications than women having standard IVF. There was a significant decrease in cancer risk after IVF (0.79, 0.69–0.91) but a suggested increase in the risk of ovarian cancer both before (2.70, 1.49–4.91) and after (2.08, 1.15–3.76) IVF. No change in mortality was observed. Conclusions  Women treated with IVF had an increased obstetric morbidity. This seems to contribute little to the well‐known increased risk of preterm delivery.