Objective To determine the prevalence and course of fear of childbirth (FoC) according to gestational age and to identify risk factors for FoC, the influence of FoC on preferred mode of delivery and self-reported need for help. Study Design Cross-sectional and cohort study Setting Urban hospital, midwifery practices, social media, maternity websites. Population Nulliparous pregnant women May 2020-January 2021. Methods Participants completed an online survey. Women who completed the survey in the first or second trimester(T0) were approached again in their third trimester(T1). Questionnaires indexing FoC, social support, anxiety, depressive symptoms, self-reported need for help, and preferred mode of delivery were included. Main outcome measures Fear of childbirth, defined as W-DEQ A score ≥ 85 Results In total, 364 women were enrolled at T0, and 118 women were included in the longitudinal analysis. Cross-sectional analysis showed a prevalence of FoC of 18.4% with no significant difference between trimesters. In the longitudinal sample, prevalence of FoC decreased from 18.6%(T0) to 11.0%(T1), P=0.004. W-DEQ A mean scores decreased significantly, P<0.001, although 41 (34.7%) women showed an increase in scores. FoC was associated with elevated anxiety, less family support, prenatal care of the obstetrician by choice, preference for a cesarean section, and for pain relief. Women with FoC were more likely to actively seek for help compared to women without FoC. Conclusions While FoC is common, prevalence decreases over the course of pregnancy. Because women with FoC are actively seeking for help, this problem should be addressed better, and help should be offered.