Compared to women who are legal residents of Geneva, undocumented migrants had more unintended pregnancies, use preventive measures less frequently, delayed prenatal care more, and were exposed to more violence during pregnancy.
Delayed use of prenatal care remains problematic among undocumented migrants in Geneva: the first pregnancy visit occurred more than 4 weeks later than for women with a legal residence permit, and prenatal care began during the first trimester in only 63% of the undocumented compared to 96% of controls. Similar difficulties were observed for undocumented pregnant migrants in Colorado, US . The United Nations has indicated that one high priority "Millennium goal" is to improve maternal health throughout the world . Even if the existence of a free health care unit facilitates access to care, there is clearly a need to find ways to improve use of care and particularly early pregnancy care for undocumented women. In our experience, the cost of health care is a major barrier, particularly in countries like Switzerland where each individual has to arrange and pay for their own health insurance and where over 90% of the undocumented migrants lack health insurance. Improved health care access for undocumented migrants requires creative financial solutions, including being free or of minimal charge, but also language competencies of health care providers and administrative staff. Furthermore, protection has to be guaranteed: undocumented migrants would hardly be likely to contact a health care provider if they feared potential notification of their stay to the police and any other subsequent legal sequelae.
Undocumented pregnant migrants in Geneva were mostly young and single Latin-American women of whom an important percentage lacked social and emotional support. They were living in poor housing conditions and one in five of them had no or only an occasional relationship with the father of their child.
Despite our findings that prenatal care was delayed and preterm births were more frequent in undocumented migrants (9%vs.4%, p = 0.09), health outcomes such as complications during pregnancy, delivery, and post-partum were similar in both groups, and neonatal outcomes even tended to be slightly better in the undocumented. These relatively good health outcomes might be explained by a selection of the fittest women during migration, which has been conceptualized under the "healthy migrant effect" [6, 12]. Alternatively, it could be hypothesized that good birth outcomes might be explained by the fact that women who were lost to follow-up might have had worse risks. Nonetheless, when comparing undocumented women who delivered to those who left the country, no particular risk profile could be identified.
Considering drugs and alcohol abuse, undocumented pregnant migrants showed a healthier pattern than control women. Prenatal alcohol exposure is a major cause of foetal defects and neurodevelopmental problems and the most frequent cause of avoidable mental retardation . In our population, most women stopped their alcohol intake with the onset of pregnancy. Nevertheless, 30% of the control group and 12% of undocumented migrants consumed alcohol during pregnancy with a notable proportion of binge drinking (16% versus 6%). Healthcare professionals must be aware of this major problem.
Seroprevalences in undocumented women corresponded to their countries of origin, mainly Latin-America. They were better immunized against Toxoplasma gondii and CMV but less so against rubella than controls. Toxoplasma immunity prevalence among controls was 42%, similar to what has been found for the Swiss general population (46%) , whereas the Toxoplasma immunity prevalence in Latin-America (67%) is similar to that of the undocumented migrants in this study. Seroprevalence of rubella is known to vary across countries, with lower rates in Latin-America [15, 16], where congenital rubella syndrome is an under-recognized public health problem .
The high prevalence of unintended pregnancies among undocumented migrants (75%) highlights an important public health issue and confirms our previous study where we found a similar rate among undocumented migrants in Geneva . In contrast, the control group reported only 20% of unintended pregnancies. To our knowledge, this is the first time that unintended pregnancies resulting in live births have been studied for women with a legal residency permit in Switzerland. International comparisons show large differences between and uncertainties within countries, which indicates the complexity of measurement of unintended pregnancies [18, 19]: 10 to 31% in Great-Britain [20, 21], 16 to 20% in France , and up to 55% in Colombia resulting in live births . In the US 49% of all pregnancies are estimated to be unintended , of which 33% to 49% result in live births, with large differences between the states [25, 26]. Known factors associated with unintendedness [23, 27, 28], such as delayed prenatal care, not being married, or exposure to violence were also observed in our study.
Exposure to violence has frequently been reported, particularly among women with unintended pregnancies and during pregnancy, as was the case for 11% of the undocumented migrants in our study [23, 29]. Consequently, it is important to ask pregnant women systematically and repeatedly about violence exposure . It was unexpected that only 1.3% of the controls reported being exposed to violence during pregnancy, which contrasts with 7% found in a survey conducted 10 years before at the same hospital . The latter study investigated violence prevalence as a major outcome, which could have influenced the women's responses and explain the higher prevalence.
Seventy-nine percent of the women with unintended pregnancies did not use any (48%) or used unreliable (31%) contraceptive measures, and 61% were unaware of emergency contraception (Levonorgestrel) which can prevent pregnancy up to 72 hours after intercourse and can be obtained without medical prescription in Geneva [32, 33]. The important difficulties concerning knowledge, access, and use of preventive measures are also illustrated by the under-utilisation of cervical smear (Pap) tests and breast examination. Pap test under-use corresponds to the well-known lack of lifetime screening in many parts in Latin-America and underlines the need for language- and culturally-appropriate education [34, 35].
The relationship between residency permit and the main outcomes might be influenced by age, origin, civil status, education, duration of residence in Geneva, and having emotional support and/or a family member in Geneva. Using multiple logistic regression analysis we found that civil status was an important confounder of the relationship between residency status and three main outcomes: unintendedness of pregnancy, delayed prenatal care, and less use of Pap tests by undocumented migrants. Other potential confounders had no significant influence on the main outcome in our study and were therefore not included in the adjusted analyses.
Our study confirms the close relationship between illegality and poverty. Undocumented migrants earned 13 SFr per hour (≈8 Euro) which is 40% lower than the minimal mandatory hourly wage in Geneva. Furthermore, undocumented migrant status is associated with isolation, stigma, and fear. Further research is needed to better elucidate these complex influences in order to implement effective programmatic solutions for the main problems pointed out here.
The present study has several strengths. First, to the best of our knowledge, that pregnancy characteristics have been studied in undocumented migrants and compared to a local control group is unique in Europe. Second, we prospectively included a relatively large systematic sample from this hard-to-reach population. Third, we investigated for the first time unintended pregnancies resulting in live births for women with a legal residency permit in Switzerland.
Some limitations of the present study include: First, fifty-three undocumented women (33%) left Geneva and were considered as lost to follow-up but their baseline characteristics did not differ from women who delivered at the women's hospital. Socio-demographic variables were missing for up to 24% of the study participants. On the other hand, except for knowledge of the emergency contraceptive pill, other data on preventive measures, histories of voluntary pregnancy termination and violence, as well as blood tests were missing for less than 10% of the study participants. Second, the sample size limits the power of the study. Third, the time of data collection was not identical for both study groups: first to third trimester for undocumented migrants vs. the last trimester for controls. This difference might be neglectable for the large majority of the questions; nevertheless it might have influenced responses concerning intendedness of pregnancy. However, when comparing unintendedness by trimester, no significant difference was found for undocumented women. Fourth, potential reporting bias has to be considered, as the study group was not blinded and midwives might have been more probing to detect daily-life difficulties among undocumented migrants. However, the two midwives who administered the questionnaire provided the same quality and frequency of clinical follow-up to undocumented migrants as to insured women with a residency permit and they were trained to administer the questionnaires in a precise and neutral way similarly for both groups. Fifth, undocumented women might not be representative of the total undocumented population of Geneva. However, several aspects do lead us to believe that this study reached a substantial proportion of pregnant, undocumented women in Geneva and is therefore representative of them: 1) The free medical care unit is well known by this hard-to-reach population; 2) The proportion of Latin-Americans (84%) is similar to that found by other sources: for example, in investigating the origins of undocumented workers, the Geneva trade union recently found 76% were Latin-Americans ; 3) In order to achieve optimal participation, undocumented women were enrolled in collaboration with the woman's hospital, which is the only public obstetrical hospital in Geneva and the only place where uninsured and undocumented women can deliver at low or no cost. Finally, it might still be possible that the study sample still differs from the whole undocumented population of Geneva, which is unknown by definition and thus not officially enumerated. Although our control group was not a random sample from the general population, it was obtained by systematically sampling all the women with valid residence permits who were seen on selected days at the same hospital by the same midwife during the same time period that the sample of undocumented migrants was obtained.