Introduction
For long, it is known that early and adequate prenatal care is important to reduce perinatal complications, such as preterm birth.1, 2 The World Health Organization recommends at least 8 visits in total and the first visit to take place at 13 weeks gestational age at latest.3 Early prenatal care is important to assess the gestational age, which may be helpful later on in managing preterm birth, prolonged pregnancy or complications.4 Early antenatal care is also essential to enable timely screening for anaemia and rubella, to assess Rh and AB0 blood typing, to offer non-invasive genetic testing and to address potential risk factors such as high body mass index and domestic violence.5 Furthermore, considering the great impact of circumstances during pregnancy, timely education of pregnant people regarding healthy behaviours, including nutrition, supplement intake, smoking and alcohol cessation and exercise, is similarly important.5
In the Netherlands, antenatal care is generally accessible to pregnant people. All expenses, except travel costs, are covered by the basic health care fund, and specific government arrangements guarantee free obstetric care for pregnant people without health insurance.6 Still, in 40% of the births in Rotterdam, a multi-ethnic city with large social and perinatal health inequalities,7 antenatal care started only after ten weeks of pregnancy.8 Previous research pointed at several predictors for a late antenatal care initiation, including young age, being single, lower socio-economic position, migration background, mental health problems, poorer language ability and higher parity.9-14 Many of these factors are also predictors of preterm birth.15, 16 Together, these observations underline the so called ‘Inverse Care Law’, describing that those who need care the most, have the least access to care.17
Thus far, most studies evaluated a wide range of predictors for late antenatal care initiation, without discerning between factors that are and are not modifiable. A potentially important modifiable reason for late antenatal care initiation is late recognition of the pregnancy.18, 19 A study in the United States showed that participants who recognized the pregnancy early (within 6 weeks after the first day of the last menstrual period) initiated antenatal care 6 times more often timely (<12 weeks of gestation) than those with later pregnancy recognition, after adjustment for socioeconomic variables.18 The aim of this study is therefore to investigate predictors in timing of antenatal care initiation; and to assess whether some of these inequalities would be reduced had everyone recognized the pregnancy early.