For non-Western migrants the perinatal mortality rate (PMR) was up to 9 times higher in their country of birth than in Norway (Table ). The difference in PMR between the country of birth and the host country was largest for offspring of Afghan, Iraqi and Somali women. Nevertheless, the risk of perinatal death was higher in offspring of migrant women than in offspring of Norwegian women. For Afghans the risk of perinatal death was four times higher than in Norwegians.
The first WHO report on perinatal mortality in 1995 initiated improved recording of country specific PMRs [9
]. However, the accuracy of reporting and the legal requirements for notification of fetal deaths and live births still vary by country [7
]. The WHO perinatal mortality estimates cannot be interpreted as precise figures of the PMR in each country. In particular, the PMRs in war affected countries such as Afghanistan and Somalia need to be interpreted with caution. The WHO methodology for estimating PMRs, however, has improved since 1995 [7
]. Sri Lankan migrants in Norway are mainly Tamils from the conflict affected regions of Sri Lanka [15
]. Rates of stillbirths, neonatal and maternal deaths have been reported to be higher in these regions than in other regions of Sri Lanka [16
]. We used the PMR for Sri Lanka as a whole in our study. The difference in PMR between Sri Lanka and Norway may therefore represent underestimates for the Tamils.
Due to the time consuming process of updating national registries, we lacked complete information on perinatal deaths by country of birth beyond 2005. However, there are no indications that our results should not be valid beyond this time period. To our knowledge, no prior studies have compared PMRs for migrants in their host country with the PMRs in their countries of birth. However, risks of perinatal death in migrants as compared to the native population in the host country have been reported. Refugees and non-European migrants in Europe and also foreign born blacks in the United States have high excess perinatal mortality compared to the native population [5
]. Studies from Norway and Sweden report increased risk of perinatal death in offspring of Somali women in particular [5
]. In the United Kingdom offspring of women born in Pakistan are at high risk [20
]. Overall the PMRs in these Western countries, in particular the Scandinavian countries, are among the lowest in the world [7
]. We are not aware of prior studies that have reported the PMRs for Sri Lankan, Pilipino, Iraqi, Thai and Afghan migrants from any European country.
Our results suggest that migrants from countries with a high PMR benefit substantially from the health care services in Norway. The difference between the PMR in Norway and country of birth may thus be an indirect measure of the effect of quality health care available to all women in attaining low PMR. However, low PMRs in migrants in Norway may also be explained by other factors that affect women’s health, such as improved housing, sanitation and educational opportunities [21
] in Norway.
Despite access to quality health care in Norway, most migrant groups have a higher PMR than Norwegian women. Offspring of migrants also have overall higher stillbirth and early neonatal mortality rates than offspring of Norwegian women. The increased risk of perinatal death in migrants cannot be explained by a disproportional increase in risk of stillbirths or of early neonatal deaths. Furthermore, the small differences between migrant and Norwegian women in the prevalence of preterm births and of perinatal deaths in preterm deliveries do not provide further understanding of the excess perinatal mortality in migrants.
Individual information on migration status, social and behavioral factors that could explain the differences in risk were not available in our data. While diabetes and preeclampsia have been associated with increased risk of perinatal death [19
], we do not know whether information on maternal diseases in The Medical Birth Registry of Norway is valid for migrant women [22
]. The reported differences in perinatal mortality between groups in our study should, however, encourage further research on risk factors in these migrant groups.
Some differences between migrants groups that could explain differences in perinatal mortality are discussed below.
The majority of Afghan, Iraqi, Somali, Vietnamese and Sri Lankan women in Norway are either refugees or have migrated for unification with a family member with refugee status in Norway [24
]. Refugees are more likely to have been affected by malnutrition, psychological distress and lack of health care services than people who have been able to plan their migration [25
]. In Norway, refugees and their families have substantially worse living conditions than the rest of the population, especially if they are newly settled [26
]. As the majority of Afghan, Iraqi and Somali migrants had lived in Norway for less than five years in 2004 [26
], we assume that their acculturation process is at a premature stage. Their health seeking behavior and cultural practices concerning pregnancy and childbirth may thus be similar to those in their countries of birth. Cultural practices such as reducing food intake to avoid large sized infants and thereby complicated deliveries, have been reported in Somali women residing in Sweden [27
]. The low risk of perinatal death in Iraqi migrants as compared to other migrant groups, may partially be due to a better adaption to the Norwegian health care system, since Iraq had a well-functioning health care system and low PMR in the 1980s [28
]. Though, after the initiation of the United Nations sanctions against Iraq and the Gulf war in 1990, the PMR increased [29
Vietnamese women may have fewer barriers in accessing healthcare as the majority have lived in Norway for over 10 years and are well-integrated in the Norwegian society [22
]. Also, the low risk of perinatal death in Vietnamese migrants in Norway may be due to their background as political refugees and an advantageous socioeconomic background [30
]. Such selection, described as the “healthy migrant effect” may explain the low PMR for some migrant groups in Norway [31
The majority of Pakistani women migrate to Norway after marrying a man with Pakistani background living in Norway [32
]. In Pakistani migrants consanguineous marriages are common and may contribute to 29% of the stillbirths and infant deaths in this group [33
]. The lower risk of perinatal death in offspring of Thai and Filipino women compared to other migrant groups may partially be associated with 84–95 % of these women being married to a Norwegian man [32
]. This may ease their acculturation process into the Norwegian society, making it easier to pass cultural and communication barriers in accessing health care services.
As perceptions of somatic symptoms may differ by culture [20
], there may also be cultural determinants of perinatal care. Non-Western migrants in Norway and in the Netherlands have been found to be less prone to attend the antenatal care program, with fewer numbers of antenatal visits and subsequently poorer detection of complications [34
]. Furthermore, inadequate communication in perinatal care to non-Western migrants has been reported in Norway, Sweden and the Netherlands [35
], suggesting that problems in interpretation of clinical symptoms may have been disturbed [38
]. Suboptimal factors in perinatal care, such as inadequate medication, insufficient surveillance of intrauterine growth restriction (IUGR) and refusal of Caesarean-sections by mothers has been reported in Somali women in Sweden [37
], and may be due to miscommunication. The mechanisms behind the health seeking behavior of migrant women and the cultural framework used by these groups in articulating their symptoms are insufficiently understood.