The incidence and maternal age distribution of abdominal wall defects in Norway and Arkhangelskaja Oblast in Russia

Abstract

Objectives. To determine the foetal incidence of isolated anterior abdominal wall defects (gastroschisis and omphalocele) in the Arkhangelskaja Oblast (AO) in Russia and in Norway, as well as to study the maternal -age distribution of these defects. Study Design. A register -based incidence study. Methods. All registered foetuses and newborns with at least weeks of gestation in the populations of AO (4,59) and Norway (9,708) were included. The data covered the period 995-004 in AO and 999-00 in Norway and were obtained from the malformation register in AO and the Medical Birth Registry of Norway. Results. The majority of the outcomes with a defect were liveborn in Norway (65%), while in AO the majority were spontaneously or medically aborted (59%). The incidence of anterior abdominal wall defects was 5.4/10,000 (95% confidence limits: ±1.7) in AO and 5.1/10,000 (±0.8) in Norway, and the ratio of omphalocele to gastroschisis was . in AO vs. 0.9 in Norway. Gastroschisis was inversely associated with maternal age in Norway. Conclusions. Despite a difference in maternal age distribution, there was no difference in the incidence of abdominal wall defects in AO and Norway. Gastroschisis was associated with young maternal age only in Norway, and the higher incidence in maternal age groups younger than 5 warrants further studies about aetiological factors associated with young maternal age.

The incidence of neural tube defects in Norway and the Arkhangelskaja Oblast in Russia and the association with maternal age

“…AO has had a system for collecting data about birth defects and perinatal and infant mortality since 1995, and has participated in a monitoring program that includes compulsory notification and registration of congenital defects (12). Additional details have been reported (13, 15, 21).…”

“…Their center of medical genetics registered spontaneous abortuses with defects. More details about the registration of newborns and medical abortuses with defects have been previously reported (13, 15).…”

“…In Russia, a middle‐income country, the possibility for epidemiological studies concerning birth defects has been impeded by a lack of systematic population‐based computerized registration of all deliveries. Recently, however, some regions have put into place a program for population‐based registration of newborns and fetuses with defects (12) and a few studies have been published (13–15). In Norway, the incidence of NTD at birth has been published for the periods 1967–1981 and 1967–1992 (16, 17).…”

Assessing the trend of gastroschisis prevalence in China from 1996 to 2007 using two analytical methods

“…The prevalence of gastroschisis in recent years has a remarkably increasing trend in some areas but has remained unchanged in other areas; in gen-eral, gastroschisis prevalence has increased significantly since the 1970s (Baerg et al, 2003;Reid et al, 2003;Arnold, 2004;Alvarez and Burd, 2007). Additionally, the relevant studies that mainly focused on the risk factors of gastroschisis incidence, such as race, age, smoking, and drug use of the mothers, consistently showed that the increasing gastroschisis prevalence may be associated with the change in the mother's age (Hougland et al, 2005;Petrova and Vaktskjold, 2009;Feldkamp and Botto, 2008;Forrester and Merz, 2006;Loane et al, 2007;Nichols et al, 1997).…”

Under-reporting of major birth defects in Northwest Russia: a registry-based study

“…They focus on prevalence rates and time trends, but it is difficult to conduct a systematic scientific investigation (e.g. of case control design) of risk factors due to a lack of information in such registries [12,13]. In addition, there is no experience in Russia at the local or national level of linking such data with birth registries.…”